miércoles, 31 de marzo de 2010
martes, 23 de marzo de 2010
Definition,puberty, Psychology, Sexuality
Adolescence (from the Latin: adolescere meaning "to grow up") is a transitional stage of physical and mental human development that occurs between childhood and adulthood. This transition involves biological (i.e. pubertal), social, and psychological changes, though the biological or physiological ones are the easiest to measure objectively. Historically, puberty has been heavily associated with teenagers and the onset of adolescent development.[1][2] In recent years, however, the start of puberty has had somewhat of an increase in preadolescence (particularly females, as seen with early and precocious puberty); adolescence has had an occasional extension beyond the teenage years (typically males). These changes have made it more difficult to rigidly define the time frame in which adolescence occurs.[3][4][5]
The end of adolescence and the beginning of adulthood varies by country and by function, and furthermore even within a single nation-state or culture there can be different ages at which an individual is considered to be (chronologically and legally) mature enough to be entrusted by society with certain tasks. Such milestones include, but are not limited to, driving a vehicle, having legal sexual relations, serving in the armed forces or on a jury, purchasing and drinking alcohol, voting, entering into contracts, completing certain levels of education, and marrying.
Adolescence is usually accompanied by an increased independence allowed by the parents or legal guardians and less supervision, contrary to the preadolescence stage.
Puberty
Upper body of teenage boy. The structure has changed to resemble an adult form.Main article: Puberty
Puberty is a period of several years in which rapid physical growth and psychological changes occur, culminating in sexual maturity. The average onset of puberty is at 10 for girls and age 12 for boys.[6] Every person's individual timetable for puberty is influenced primarily by heredity, although environmental factors, such as diet and exercise, also exert some influence.[6][7][8] These factors can also contribute to delayed puberty.
Puberty begins with a surge in hormone production, which in turn, causes a number of physical changes.[6] It is also the stage of life in which a child develops secondary sex characteristics (for example, a deeper voice and larger adam's apple in boys, and development of breasts and more curved and prominent hips in girls) as his or her hormonal balance shifts strongly towards an adult state. This is triggered by the pituitary gland, which secretes a surge of hormonal agents into the blood stream, initiating a chain reaction. The male and female gonads are subsequently activated, which puts them into a state of rapid growth and development; the triggered gonads now commence the mass production of the necessary chemicals. The testes primarily release testosterone, and the ovaries predominantly dispense estrogen. The production of these hormones increases gradually until sexual maturation is met. Some boys may develop gynecomastia due to an imbalance of sex hormones, tissue responsiveness or obesity.[9][10] Put simply, puberty is the time when a child's body starts changing into an adult's body.[6]
Facial hair in males normally appears in a specific order during puberty: The first facial hair to appear tends to grow at the corners of the upper lip, typically between 14 to 16 years of age.[11][12] It then spreads to form a moustache over the entire upper lip. This is followed by the appearance of hair on the upper part of the cheeks, and the area under the lower lip.[11] The hair eventually spreads to the sides and lower border of the chin, and the rest of the lower face to form a full beard.[11] As with most human biological processes, this specific order may vary among some individuals. Facial hair is often present in late adolescence, around ages 17 and 18, but may not appear until significantly later.[12][13] Some men do not develop full facial hair for 10 years after puberty.[12] Facial hair will continue to get coarser, darker and thicker for another 2–4 years after puberty.[12]
The major landmark of puberty for males is the first ejaculation, which occurs, on average, at age 13.[14] For females, it is menarche, the onset of menstruation, which occurs, on average, between ages 12 and 13.[7] The age of menarche is influenced by heredity, but a girl's diet and lifestyle contribute as well.[7] Regardless of genes, a girl must have certain proportion of body fat to attain menarche.[7] Consequently, girls who have a high-fat diet and who are not physically active begin menstruating earlier, on average, than girls whose diet contains less fat and whose activities involve fat reducing exercise (e.g. ballet and gymnastics).[7][8] Girls who experience malnutrition or are in societies in which children are expected to perform physical labor also begin menstruating at later ages.[7]
The timing of puberty can have important psychological and social consequences. Early maturing boys are usually taller and stronger than their friends.[15] They have the advantage in capturing the attention of potential partners and in becoming hand-picked for sports. Pubescent boys often tend to have a good body image, are more confident, secure, and more independent.[16] Late maturing boys can be less confident because of poor body image when comparing themselves to already developed friends and peers. However, early puberty is not always positive for boys; early sexual maturation in boys can be accompanied by increased aggressiveness due to the surge of hormones that affect them.[16] Because they appear older than their peers, pubescent boys may face increased social pressure to conform to adult norms; society may view them as more emotionally advanced, despite the fact that their cognitive and social development may lag behind their appearance.[16] Studies have shown that early maturing boys are more likely to be sexually active and are more likely to participate in risky behaviors.[17]
For girls, early maturation can sometimes lead to increased self-consciousness, though a typical aspect in maturing females.[18] Because of their bodies developing in advance, pubescent girls can become more insecure.[18] Consequently, girls that reach sexual maturation early are more likely than their peers to develop eating disorders. Nearly half of all American high school girls' diet is to lose weight.[18] In addition, girls may have to deal with sexual advances from older boys before they are emotionally and mentally mature.[19] In addition to having earlier sexual experiences and more unwanted pregnancies than late maturing girls, early maturing girls are more exposed to alcohol and drug abuse.[20] Those who have had such experiences tend to perform less well in school than their "inexperienced" age peers.[21]
By ages 15-17, girls have usually reached full physical development.[18][22] By age 16, boys are close to completing puberty,[18] which is usually achieved by ages 17 or 18.[22] Teenage and early adult males may continue to gain natural muscle growth even after puberty.[16]
Psychology
Main article: Adolescent psychology
Adolescent psychology is associated with notable changes in mood sometimes known as mood swings. Cognitive, emotional and attitudinal changes which are characteristic of adolescence, often take place during this period, and this can be a cause of conflict on one hand and positive personality development on the other.
Because the adolescents are experiencing various strong cognitive and physical changes, for the first time in their lives they may start to view their friends, their peer group, as more important and influential than their parents/guardians. Because of peer pressure, they may sometimes indulge in activities not deemed socially acceptable, although this may be more of a social phenomenon than a psychological one.[23] This overlap is addressed within the study of psychosociology.
The home is an important aspect of adolescent psychology: home environment and family have a substantial impact on the developing minds of teenagers, and these developments may reach a climax during adolescence. For example, abusive parents may lead a child to "poke fun" at other classmates when he/she is seven years old or so, but during adolescence it may become progressively worse. If the concepts and theory behind right or wrong were not established early on in a child's life, the lack of this knowledge may impair a teenager's ability to make beneficial decisions as well as allowing his/her impulses to control his/her decisions.
In the search for a unique social identity for themselves, adolescents are frequently confused about what is 'right' and what is 'wrong.' G. Stanley Hall denoted this period as one of "Storm and Stress" and, according to him, conflict at this developmental stage is normal and not unusual. Margaret Mead, on the other hand, attributed the behavior of adolescents to their culture and upbringing.[24] However, Piaget, attributed this stage in development with greatly increased cognitive abilities; at this stage of life the individual's thoughts start taking more of an abstract form and the egocentric thoughts decrease, hence the individual is able to think and reason in a wider perspective.[25]
Positive psychology is sometimes brought up when addressing adolescent psychology as well. This approach towards adolescents refers to providing them with motivation to become socially acceptable and notable individuals, since many adolescents find themselves bored, indecisive and/or unmotivated.[26]
Adolescents may be subject to peer pressure within their adolescent time span, consisting of the need to have sex, consume alcoholic beverages, use drugs, defy their parental figures, or commit any activity in which the person who is subjected to may not deem appropriate, among other things. Peer pressure is a common experience between adolescents and may result briefly or on a larger scale. If it results on a larger scale, the adolescent needs medical advice or treatment.[27]
It should also be noted that adolescence is the stage of a psychological breakthrough in a person's life when the cognitive development is rapid[28] and the thoughts, ideas and concepts developed at this period of life greatly influence one's future life, playing a major role in character and personality formation.[29]
Struggles with adolescent identity and depression usually set in when an adolescent experiences a loss. The most important loss in their lives is the changing relationship between the adolescent and their parents. Adolescents may also experience strife in their relationships with friends. This may be due to the activities their friends take part in, such as smoking, which causes adolescents to feel as though participating in such activities themselves is likely essential to maintaining these friendships. Teen depression can be extremely intense at times because of physical and hormonal changes but emotional instability is part of adolescence. Their changing mind, body and relationships often present themselves as stressful and that change, they assume, is something to be feared.[30]
Views of family relationships during adolescence are changing. The old view of family relationships during adolescence put an emphasis on conflict and disengagement and thought storm and stress was normal and even inevitable. However, the new view puts emphasis on transformation or relationships and maintenance of connectedness.
[edit] Sexuality
Main article: Adolescent sexuality
Adolescent sexuality refers to sexual feelings, behavior and development in adolescents and is a stage of human sexuality. Sexuality and sexual desire usually begins to intensify along with the onset of puberty. The expression of sexual desire among adolescents (or anyone, for that matter), might be influenced by family values and the culture and religion they have grown up in (or as a backlash to such), social engineering, social control, taboos, and other kinds of social mores.
Teenage couples at a fair in the American West.In contemporary society, adolescents also face some risks as their sexuality begins to transform. Whilst some of these such as emotional distress (fear of abuse or exploitation) and sexually transmitted diseases (including HIV/AIDS) may not necessarily be inherent to adolescence, others such as pregnancy (through failure or non-use of contraceptives) are seen as social problems in most western societies. In terms of sexual identity, all sexual orientations found in adults are also represented among adolescents.
According to anthropologist Margaret Mead and psychologist Albert Bandura, the turmoil found in adolescence in Western society has a cultural rather than a physical cause; they reported that societies where young women engaged in free sexual activity had no such adolescent turmoil.
In a 2008 study conducted by YouGov for Channel 4, 20% of 14−17-year-olds surveyed revealed that they had their first sexual experience at 13 or under.[31]
The age of consent to sexual activity varies widely between international jurisdictions, ranging from 12 to 21 years.[32]
The end of adolescence and the beginning of adulthood varies by country and by function, and furthermore even within a single nation-state or culture there can be different ages at which an individual is considered to be (chronologically and legally) mature enough to be entrusted by society with certain tasks. Such milestones include, but are not limited to, driving a vehicle, having legal sexual relations, serving in the armed forces or on a jury, purchasing and drinking alcohol, voting, entering into contracts, completing certain levels of education, and marrying.
Adolescence is usually accompanied by an increased independence allowed by the parents or legal guardians and less supervision, contrary to the preadolescence stage.
Puberty
Upper body of teenage boy. The structure has changed to resemble an adult form.Main article: Puberty
Puberty is a period of several years in which rapid physical growth and psychological changes occur, culminating in sexual maturity. The average onset of puberty is at 10 for girls and age 12 for boys.[6] Every person's individual timetable for puberty is influenced primarily by heredity, although environmental factors, such as diet and exercise, also exert some influence.[6][7][8] These factors can also contribute to delayed puberty.
Puberty begins with a surge in hormone production, which in turn, causes a number of physical changes.[6] It is also the stage of life in which a child develops secondary sex characteristics (for example, a deeper voice and larger adam's apple in boys, and development of breasts and more curved and prominent hips in girls) as his or her hormonal balance shifts strongly towards an adult state. This is triggered by the pituitary gland, which secretes a surge of hormonal agents into the blood stream, initiating a chain reaction. The male and female gonads are subsequently activated, which puts them into a state of rapid growth and development; the triggered gonads now commence the mass production of the necessary chemicals. The testes primarily release testosterone, and the ovaries predominantly dispense estrogen. The production of these hormones increases gradually until sexual maturation is met. Some boys may develop gynecomastia due to an imbalance of sex hormones, tissue responsiveness or obesity.[9][10] Put simply, puberty is the time when a child's body starts changing into an adult's body.[6]
Facial hair in males normally appears in a specific order during puberty: The first facial hair to appear tends to grow at the corners of the upper lip, typically between 14 to 16 years of age.[11][12] It then spreads to form a moustache over the entire upper lip. This is followed by the appearance of hair on the upper part of the cheeks, and the area under the lower lip.[11] The hair eventually spreads to the sides and lower border of the chin, and the rest of the lower face to form a full beard.[11] As with most human biological processes, this specific order may vary among some individuals. Facial hair is often present in late adolescence, around ages 17 and 18, but may not appear until significantly later.[12][13] Some men do not develop full facial hair for 10 years after puberty.[12] Facial hair will continue to get coarser, darker and thicker for another 2–4 years after puberty.[12]
The major landmark of puberty for males is the first ejaculation, which occurs, on average, at age 13.[14] For females, it is menarche, the onset of menstruation, which occurs, on average, between ages 12 and 13.[7] The age of menarche is influenced by heredity, but a girl's diet and lifestyle contribute as well.[7] Regardless of genes, a girl must have certain proportion of body fat to attain menarche.[7] Consequently, girls who have a high-fat diet and who are not physically active begin menstruating earlier, on average, than girls whose diet contains less fat and whose activities involve fat reducing exercise (e.g. ballet and gymnastics).[7][8] Girls who experience malnutrition or are in societies in which children are expected to perform physical labor also begin menstruating at later ages.[7]
The timing of puberty can have important psychological and social consequences. Early maturing boys are usually taller and stronger than their friends.[15] They have the advantage in capturing the attention of potential partners and in becoming hand-picked for sports. Pubescent boys often tend to have a good body image, are more confident, secure, and more independent.[16] Late maturing boys can be less confident because of poor body image when comparing themselves to already developed friends and peers. However, early puberty is not always positive for boys; early sexual maturation in boys can be accompanied by increased aggressiveness due to the surge of hormones that affect them.[16] Because they appear older than their peers, pubescent boys may face increased social pressure to conform to adult norms; society may view them as more emotionally advanced, despite the fact that their cognitive and social development may lag behind their appearance.[16] Studies have shown that early maturing boys are more likely to be sexually active and are more likely to participate in risky behaviors.[17]
For girls, early maturation can sometimes lead to increased self-consciousness, though a typical aspect in maturing females.[18] Because of their bodies developing in advance, pubescent girls can become more insecure.[18] Consequently, girls that reach sexual maturation early are more likely than their peers to develop eating disorders. Nearly half of all American high school girls' diet is to lose weight.[18] In addition, girls may have to deal with sexual advances from older boys before they are emotionally and mentally mature.[19] In addition to having earlier sexual experiences and more unwanted pregnancies than late maturing girls, early maturing girls are more exposed to alcohol and drug abuse.[20] Those who have had such experiences tend to perform less well in school than their "inexperienced" age peers.[21]
By ages 15-17, girls have usually reached full physical development.[18][22] By age 16, boys are close to completing puberty,[18] which is usually achieved by ages 17 or 18.[22] Teenage and early adult males may continue to gain natural muscle growth even after puberty.[16]
Psychology
Main article: Adolescent psychology
Adolescent psychology is associated with notable changes in mood sometimes known as mood swings. Cognitive, emotional and attitudinal changes which are characteristic of adolescence, often take place during this period, and this can be a cause of conflict on one hand and positive personality development on the other.
Because the adolescents are experiencing various strong cognitive and physical changes, for the first time in their lives they may start to view their friends, their peer group, as more important and influential than their parents/guardians. Because of peer pressure, they may sometimes indulge in activities not deemed socially acceptable, although this may be more of a social phenomenon than a psychological one.[23] This overlap is addressed within the study of psychosociology.
The home is an important aspect of adolescent psychology: home environment and family have a substantial impact on the developing minds of teenagers, and these developments may reach a climax during adolescence. For example, abusive parents may lead a child to "poke fun" at other classmates when he/she is seven years old or so, but during adolescence it may become progressively worse. If the concepts and theory behind right or wrong were not established early on in a child's life, the lack of this knowledge may impair a teenager's ability to make beneficial decisions as well as allowing his/her impulses to control his/her decisions.
In the search for a unique social identity for themselves, adolescents are frequently confused about what is 'right' and what is 'wrong.' G. Stanley Hall denoted this period as one of "Storm and Stress" and, according to him, conflict at this developmental stage is normal and not unusual. Margaret Mead, on the other hand, attributed the behavior of adolescents to their culture and upbringing.[24] However, Piaget, attributed this stage in development with greatly increased cognitive abilities; at this stage of life the individual's thoughts start taking more of an abstract form and the egocentric thoughts decrease, hence the individual is able to think and reason in a wider perspective.[25]
Positive psychology is sometimes brought up when addressing adolescent psychology as well. This approach towards adolescents refers to providing them with motivation to become socially acceptable and notable individuals, since many adolescents find themselves bored, indecisive and/or unmotivated.[26]
Adolescents may be subject to peer pressure within their adolescent time span, consisting of the need to have sex, consume alcoholic beverages, use drugs, defy their parental figures, or commit any activity in which the person who is subjected to may not deem appropriate, among other things. Peer pressure is a common experience between adolescents and may result briefly or on a larger scale. If it results on a larger scale, the adolescent needs medical advice or treatment.[27]
It should also be noted that adolescence is the stage of a psychological breakthrough in a person's life when the cognitive development is rapid[28] and the thoughts, ideas and concepts developed at this period of life greatly influence one's future life, playing a major role in character and personality formation.[29]
Struggles with adolescent identity and depression usually set in when an adolescent experiences a loss. The most important loss in their lives is the changing relationship between the adolescent and their parents. Adolescents may also experience strife in their relationships with friends. This may be due to the activities their friends take part in, such as smoking, which causes adolescents to feel as though participating in such activities themselves is likely essential to maintaining these friendships. Teen depression can be extremely intense at times because of physical and hormonal changes but emotional instability is part of adolescence. Their changing mind, body and relationships often present themselves as stressful and that change, they assume, is something to be feared.[30]
Views of family relationships during adolescence are changing. The old view of family relationships during adolescence put an emphasis on conflict and disengagement and thought storm and stress was normal and even inevitable. However, the new view puts emphasis on transformation or relationships and maintenance of connectedness.
[edit] Sexuality
Main article: Adolescent sexuality
Adolescent sexuality refers to sexual feelings, behavior and development in adolescents and is a stage of human sexuality. Sexuality and sexual desire usually begins to intensify along with the onset of puberty. The expression of sexual desire among adolescents (or anyone, for that matter), might be influenced by family values and the culture and religion they have grown up in (or as a backlash to such), social engineering, social control, taboos, and other kinds of social mores.
Teenage couples at a fair in the American West.In contemporary society, adolescents also face some risks as their sexuality begins to transform. Whilst some of these such as emotional distress (fear of abuse or exploitation) and sexually transmitted diseases (including HIV/AIDS) may not necessarily be inherent to adolescence, others such as pregnancy (through failure or non-use of contraceptives) are seen as social problems in most western societies. In terms of sexual identity, all sexual orientations found in adults are also represented among adolescents.
According to anthropologist Margaret Mead and psychologist Albert Bandura, the turmoil found in adolescence in Western society has a cultural rather than a physical cause; they reported that societies where young women engaged in free sexual activity had no such adolescent turmoil.
In a 2008 study conducted by YouGov for Channel 4, 20% of 14−17-year-olds surveyed revealed that they had their first sexual experience at 13 or under.[31]
The age of consent to sexual activity varies widely between international jurisdictions, ranging from 12 to 21 years.[32]
lunes, 22 de marzo de 2010
poli 2 Transport in plants
See this adress for more information http://www.jochemnet.de/fiu/BSC1011/BSC1011_9/index.htm
martes, 16 de marzo de 2010
Classification!!
Classification of Organisms
Organismal diversity is the product of evolution. Evolutionary paths are branched and numerous, though most arrive at dead ends with organisms which do not survive in the face of environmental change. In this lecture we consider these evolutionary paths (called lineages), ignoring for the moment the processes that carry organisms along them.
While the lineage of any given organism may have twisted repeatedly according to the whims of chance and change, key nodes may nevertheless be tracked retrospectively. These nodes consist of times of identifiable change, particularly points of divergence between two lineages (speciation events). The delineation of these nodes in organismal lineages is accomplished through fossil reconstruction of the past as well as by comparing extant organisms, looking for similarities and differences in anatomies, physiologies, genes, behaviors, etc. From this information classification and phylogenetic reconstruction is accomplished. Classification according to similarity:
Carolus Linnaeus developed a system of classification of every (then) known organism.
This system is based on creating and differentiating groups in terms of structural (and other) similarities and differences.
Linnaeus also invented binomial nomenclature to keep track of group members.
Systematics
Systematics is the study of the diversity of organisms and their evolutionary relationships.
Science of classification:
Systematics is the science of the classification of organisms.
The main goal of systematics is the discovery and codification of phylogenetic relationships between organisms.
"The term systematics often is used for taxonomy. However, many taxonomists define it in more general terms as 'the scientific study of organisms with the ultimate object of characterizing and arranging them in an orderly manner.' Any study of the nature of organisms, when the knowledge gained is used in taxonomy, is a part of systematics. Thus (systematics) encompasses disciplines such as morphology, ecology, epidemiology, biochemistry, molecular biology, and physiology." (p. 391, Prescott et al., 1996)
Taxon [sing., taxa, pl.]
A taxon is a phylogenetic grouping of organisms.
Taxonomy
Identification and classification:
Taxonomy is the science concerned with the:
identification
classification
nomenclature
of organisms.
"Taxonomy [Greek taxis, arrangement or order, and nomos, law, or nemein, to distribute or govern] is defined as the science of biological classification. In a broader sense it consists of three separate but interrelated parts: classification, nomenclature, and identification." (p. 391, Prescott et al., 1996)
Note that the terms systematics and taxonomy can often be used semantically in a nearly indistinguishable manner.
Identification
Identification is "the practical side of taxonomy, the process of determining that a particular (organism) belongs to a recognized taxon." (p. 391, Prescott et al., 1996)
Classification
Classification is "the arrangement of organisms into groups or taxa." (p. 391, Prescott et al., 1996)
Nomenclature
Name assignment:
Nomenclature is "the branch of taxonomy concerned with the assignment of names to taxonomic groups in agreement with published rules." (p. 391, Prescott et al., 1996)
Note that ideally names have taxonimic meaning, i.e., they give clues to phylogenetic relationships.
Hierarchical classification
Hierarchy of designations:
The full description of a given organism's place among all the world's organisms does not end with its binomial designation.
There exists a hierarchy of designations only the last of which describe genera and species denomination.
"A category in any rank unites groups in the level below it based on shared properties." (p. 391, Prescott et al., 1996)
The major designations, listed in terms of increasing specificity, include:
domain (empire/super-kingdom)
kingdom
phylum
class
order
family
genus
species
Various mnemonics exist to help you remember these designations from kingdom through species
Did King Peter Came Over From Geneva Switzerland?
lunes, 15 de marzo de 2010
Dichotomus key Senior 1
Activity
Create a dichotomous key using the following list of specimens: pine tree, clam, rock,
robin, tin can, deer, oak tree, mouse, dandelion, Paramecium, bicycle, ant
Here's an example in written form using these items:
1. a. Organism is living........................................................go to 4.
1. b. Organism is nonliving..................................................go to 2.
2. a. Object is metallic........................................................go to 3.
2. b. Object is nonmetallic..................................................ROCK.
3. a. Object has wheels......................................................BICYCLE.
3. b. Object does not have wheels......................................TIN CAN.
4. a. Organism is microscopic...................................PARAMECIUM.
4. b. Organism is macroscopic............................................go to 5.
5. a. Organism is a plant.....................................................go to 6.
5. b. Organism is an animal.................................................go to 8.
6. a. Plant has a woody stem..............................................go to 7.
6. b. Plant has a herbaceous stem.................................DANDELION.
7. a. Tree has needle like leaves.....................................PINE TREE.
7. b. Tree has broad leaves............................................OAK TREE.
8. a. Organism lives on land................................................go to 9.
8. b. Organism lives in water...............................................CLAM.
9. a. Organism has 4 legs or fewer......................................go to 10.
9. b. Organism has more than 4 legs...................................ANT.
10 a. Organism has fur........................................................go to 11.
10 b. Organism has feathers................................................ROBIN.
11 a. Organism has hooves.................................................DEER.
11 b. Organism has no hooves............................................MOUSE.
Create a dichotomous key using the following list of specimens: pine tree, clam, rock,
robin, tin can, deer, oak tree, mouse, dandelion, Paramecium, bicycle, ant
Here's an example in written form using these items:
1. a. Organism is living........................................................go to 4.
1. b. Organism is nonliving..................................................go to 2.
2. a. Object is metallic........................................................go to 3.
2. b. Object is nonmetallic..................................................ROCK.
3. a. Object has wheels......................................................BICYCLE.
3. b. Object does not have wheels......................................TIN CAN.
4. a. Organism is microscopic...................................PARAMECIUM.
4. b. Organism is macroscopic............................................go to 5.
5. a. Organism is a plant.....................................................go to 6.
5. b. Organism is an animal.................................................go to 8.
6. a. Plant has a woody stem..............................................go to 7.
6. b. Plant has a herbaceous stem.................................DANDELION.
7. a. Tree has needle like leaves.....................................PINE TREE.
7. b. Tree has broad leaves............................................OAK TREE.
8. a. Organism lives on land................................................go to 9.
8. b. Organism lives in water...............................................CLAM.
9. a. Organism has 4 legs or fewer......................................go to 10.
9. b. Organism has more than 4 legs...................................ANT.
10 a. Organism has fur........................................................go to 11.
10 b. Organism has feathers................................................ROBIN.
11 a. Organism has hooves.................................................DEER.
11 b. Organism has no hooves............................................MOUSE.
miércoles, 3 de marzo de 2010
WELCOME TO SCIENCE BIOLOGY
WELCOME TO SCIENCE BIOLOGY
TEACHER ING.LIZZIE VALERIANI
I WISH YOU A FUN AND PRODUCTIVE YEAR
LAB SAFETY RULES
When you study Biology you would probably have to do experiments. It is important to know what you're doing as to avoid doing something silly like poisoning yourself or blowing up the lab!
Therefore you should first read and understand the below rules about working and behaving in the laboratory before doing any experiments.
1. Never enter the laboratory unless a teacher is present.
2. Never run or play in the laboratory.
3. Never remove anything from the laboratory without your teacher's permission.
4. Never use your bare hands to transfer chemicals. Use a spatula instead.
5. Never leave experiments unattended.
6. Never smell gases directly - fan a little of the gas towards the nose instead.
7.Never look directly down the test tube or poing the mouth of a test tube towards anyone when heating.
8. Never taste anything without your teacher's permission.
9. No eating or drinking in the laboratory.
10. Never put solids in the sink.
11. Always follow strictly the instructions given.
12. Wear safety glasses whenever necessary.
13. Always read the label on a reagent bottle carefully to make sure it contains the chemical you want. Put the bottle in its original place immediately after use.
14. Always handle flammable liquids with great care and keep them away from naked flames.
15. Always handle concentrated acids and alkalis with great care.
16. Report all accidents and breakage to your teacher. If any chemicals get onto your skin or clothing, wash the affected area with a large amount of water and then report it to your teacher.
17. Always adjust the Bunsen burner to give a luminous flame when not using it (or just simply turn it off)
18. Always tie up your tie or long hair.
19. Always wash hands after experiments.
20. Don't eat anything you find in the laboratory or in the laboratory freezer!
lunes, 1 de marzo de 2010
The definition of science:
Science is not merely a collection of facts, concepts, and useful ideas about nature, or even the
Systematic Investigation of nature, although both are common definitions of science. Science is a method of investigating nature—a way of knowing about nature—that discovers reliable knowledge about nature. So science is a method of discovering reliable knowledge about science.
Reliable knowledge is a knowledge that has high probability of being true , because its veracity has been justified by a reliable method.
The method used to justify scientific knowledge and thus make it reliable, is called scientific method.
When one uses the scientific method to study or investigate nature of the universe, one way is practicing scientific thinking to deduce and analyze something and the other is through observing and experimenting.
REASONING IN SCIENCE
Learning about the scientific method is almost like saying that you are learning how to learn. You see, the scientific method is the way scientists learn and study the world around them. It can be used to study anything from a leaf to a dog to the entire Universe.
The basis of the scientific method is asking questions and then trying to come up with the answers. You could ask, "Why do dogs and cats have hair?" One answer might be that it keeps them warm. BOOM! It's the scientific method in action. (OK, settle down.)
QUESTIONS AND ANSWERS
Just about everything starts with a question. Usually, scientists come up with questions by looking at the world around them. "Hey look! What's that?" See that squiggly thing at the end of the sentence? A question has been born.
So you've got a scientist. When scientists see something they don't understand they have some huge urge to answer questions and discover new things. It's just one of those scientist personality traits. The trick is that you have to be able to offer some evidence that confirms every answer you give. If you can't test your answer, other scientists can't test it to see if you were right or not.
As more questions are asked, scientists work hard and come up with a bunch of answers. Then it is time to organize. One of the cool things about science is that other scientists can learn things from what has already been established. They don't have to go out and test everything again and again. That's what makes science special: it builds on what has been learned before.
This process allows the world to advance, evolve, and grow. All of today's advancements are based on the achievements of scientists who already did great work. Think about it this way: you will never have to show that water (H2O) is made up of one oxygen (O) and two hydrogen (H) atoms. Many scientists before you have confirmed that fact. It will be your job as a new scientist to take that knowledge and use it in your new experiments.
EXPERIMENTAL EVIDENCE
Experimental evidence is what makes all of the observations and answers in science valid (truthful or confirmed). The history of evidence and validations show that the original statements were correct and accurate. It sounds like a simple idea, but it is the basis of all science. Statements must be confirmed with loads of evidence. Enough said.
Scientists start with observations and then make a hypothesis (a guess), and then the fun begins. They must then prove their hypothesis with trials and tests that show why their data and results are correct. They must use controls, which are quantitative (based on values and figures, not emotions). Science needs both ideas (the hypothesis) and facts (the quantitative results) to move forward. Scientists can then examine their data and develop newer ideas. This process will lead to more observation and refinement of hypotheses.
THE WHOLE PROCESS
There are different terms used to describe scientific ideas based on the amount of confirmed experimental evidence.
Hypothesis
- a statement that uses a few observations
- an idea based on observations without experimental evidence
Theory
- uses many observations and has loads of experimental evidence
- can be applied to unrelated facts and new relationships
- flexible enough to be modified if new data/evidence introduced
Law
- stands the test of time, often without change
- experimentally confirmed over and over
- can create true predictions for different situations
- has uniformity and is universal
You may also hear about the term "model." A model is a scientific statement that has some experimental validity or is a scientific concept that is only accurate under limited situations. Models do not work or apply under all situations in all environments. They are not universal ideas like a law or theory
Introduction to science
The definition of science:
Science is not merely a collection of facts, concepts, and useful ideas about nature, or even the
Systematic Investigation of nature, although both are common definitions of science. Science is a method of investigating nature—a way of knowing about nature—that discovers reliable knowledge about nature. So science is a method of discovering reliable knowledge about science.
Reliable knowledge is a knowledge that has high probability of being true , because its veracity has been justified by a reliable method.
The method used to justify scientific knowledge and thus make it reliable, is called scientific method.
When one uses the scientific method to study or investigate nature of the universe, one is practicing scientific thinking to deduce and analyze something and the other is through observing and experimenting.
REASONING IN SCIENCE
Learning about the scientific method is almost like saying that you are learning how to learn. You see, the scientific method is the way scientists learn and study the world around them. It can be used to study anything from a leaf to a dog to the entire Universe.
The basis of the scientific method is asking questions and then trying to come up with the answers. You could ask, "Why do dogs and cats have hair?" One answer might be that it keeps them warm. BOOM! It's the scientific method in action. (OK, settle down.)
QUESTIONS AND ANSWERS
Just about everything starts with a question. Usually, scientists come up with questions by looking at the world around them. "Hey look! What's that?" See that squiggly thing at the end of the sentence? A question has been born.
So you've got a scientist. When scientists see something they don't understand they have some huge urge to answer questions and discover new things. It's just one of those scientist personality traits. The trick is that you have to be able to offer some evidence that confirms every answer you give. If you can't test your answer, other scientists can't test it to see if you were right or not.
As more questions are asked, scientists work hard and come up with a bunch of answers. Then it is time to organize. One of the cool things about science is that other scientists can learn things from what has already been established. They don't have to go out and test everything again and again. That's what makes science special: it builds on what has been learned before.
This process allows the world to advance, evolve, and grow. All of today's advancements are based on the achievements of scientists who already did great work. Think about it this way: you will never have to show that water (H2O) is made up of one oxygen (O) and two hydrogen (H) atoms. Many scientists before you have confirmed that fact. It will be your job as a new scientist to take that knowledge and use it in your new experiments.
EXPERIMENTAL EVIDENCE
Experimental evidence is what makes all of the observations and answers in science valid (truthful or confirmed). The history of evidence and validations show that the original statements were correct and accurate. It sounds like a simple idea, but it is the basis of all science. Statements must be confirmed with loads of evidence. Enough said.
Scientists start with observations and then make a hypothesis (a guess), and then the fun begins. They must then prove their hypothesis with trials and tests that show why their data and results are correct. They must use controls, which are quantitative (based on values and figures, not emotions). Science needs both ideas (the hypothesis) and facts (the quantitative results) to move forward. Scientists can then examine their data and develop newer ideas. This process will lead to more observation and refinement of hypotheses.
THE WHOLE PROCESS
There are different terms used to describe scientific ideas based on the amount of confirmed experimental evidence.
Hypothesis
- a statement that uses a few observations
- an idea based on observations without experimental evidence
Theory
- uses many observations and has loads of experimental evidence
- can be applied to unrelated facts and new relationships
- flexible enough to be modified if new data/evidence introduced
Law
- stands the test of time, often without change
- experimentally confirmed over and over
- can create true predictions for different situations
- has uniformity and is universal
You may also hear about the term "model." A model is a scientific statement that has some experimental validity or is a scientific concept that is only accurate under limited situations. Models do not work or apply under all situations in all environments. They are not universal ideas like a law or theory
Science is not merely a collection of facts, concepts, and useful ideas about nature, or even the
Systematic Investigation of nature, although both are common definitions of science. Science is a method of investigating nature—a way of knowing about nature—that discovers reliable knowledge about nature. So science is a method of discovering reliable knowledge about science.
Reliable knowledge is a knowledge that has high probability of being true , because its veracity has been justified by a reliable method.
The method used to justify scientific knowledge and thus make it reliable, is called scientific method.
When one uses the scientific method to study or investigate nature of the universe, one is practicing scientific thinking to deduce and analyze something and the other is through observing and experimenting.
REASONING IN SCIENCE
Learning about the scientific method is almost like saying that you are learning how to learn. You see, the scientific method is the way scientists learn and study the world around them. It can be used to study anything from a leaf to a dog to the entire Universe.
The basis of the scientific method is asking questions and then trying to come up with the answers. You could ask, "Why do dogs and cats have hair?" One answer might be that it keeps them warm. BOOM! It's the scientific method in action. (OK, settle down.)
QUESTIONS AND ANSWERS
Just about everything starts with a question. Usually, scientists come up with questions by looking at the world around them. "Hey look! What's that?" See that squiggly thing at the end of the sentence? A question has been born.
So you've got a scientist. When scientists see something they don't understand they have some huge urge to answer questions and discover new things. It's just one of those scientist personality traits. The trick is that you have to be able to offer some evidence that confirms every answer you give. If you can't test your answer, other scientists can't test it to see if you were right or not.
As more questions are asked, scientists work hard and come up with a bunch of answers. Then it is time to organize. One of the cool things about science is that other scientists can learn things from what has already been established. They don't have to go out and test everything again and again. That's what makes science special: it builds on what has been learned before.
This process allows the world to advance, evolve, and grow. All of today's advancements are based on the achievements of scientists who already did great work. Think about it this way: you will never have to show that water (H2O) is made up of one oxygen (O) and two hydrogen (H) atoms. Many scientists before you have confirmed that fact. It will be your job as a new scientist to take that knowledge and use it in your new experiments.
EXPERIMENTAL EVIDENCE
Experimental evidence is what makes all of the observations and answers in science valid (truthful or confirmed). The history of evidence and validations show that the original statements were correct and accurate. It sounds like a simple idea, but it is the basis of all science. Statements must be confirmed with loads of evidence. Enough said.
Scientists start with observations and then make a hypothesis (a guess), and then the fun begins. They must then prove their hypothesis with trials and tests that show why their data and results are correct. They must use controls, which are quantitative (based on values and figures, not emotions). Science needs both ideas (the hypothesis) and facts (the quantitative results) to move forward. Scientists can then examine their data and develop newer ideas. This process will lead to more observation and refinement of hypotheses.
THE WHOLE PROCESS
There are different terms used to describe scientific ideas based on the amount of confirmed experimental evidence.
Hypothesis
- a statement that uses a few observations
- an idea based on observations without experimental evidence
Theory
- uses many observations and has loads of experimental evidence
- can be applied to unrelated facts and new relationships
- flexible enough to be modified if new data/evidence introduced
Law
- stands the test of time, often without change
- experimentally confirmed over and over
- can create true predictions for different situations
- has uniformity and is universal
You may also hear about the term "model." A model is a scientific statement that has some experimental validity or is a scientific concept that is only accurate under limited situations. Models do not work or apply under all situations in all environments. They are not universal ideas like a law or theory
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