Unit One Review Answers

1. R: Reproduce offspring either sexually (two parents) or asexually (one parent making clones).

H: Homeostasis. All organisms have physiological mechanisms to try to help them maintain a stable balanced environment inside their cells and outside their cells.

C: Cells. All life forms consist of one or more cells

A: Adapt. All life forms have structural, behavioural, physiological adaptations to help them survive in a given environment.

G: Grow. All life forms grow and develop.

E: Energy. All life forms take in energy from their environment and transform that energy.

R: Respond: All life forms have the ability to detect changes in their environment and respond appropriately to help them survive.

2. Homeostasis is defined above. Examples include shivering to warm up the body, sweating to cool it down, breathing faster to take in O2 and give off CO2 during exercise etc.

3. Abiogenesis means “producing without life”, it was the old theory that stated that living things could come from non-living things. It is also known as “Spontaneous Generation”

4. Redi: Rotting meat did not turn into maggots when mesh was used to keep the flies off of the meat. – living did not come from non-living.

Needham : Boiled broth in fairly well-sealed flasks did turn into thousands and thousands of microbes. - Living did come from non-living

Spallanzani: Broth boiled much longer and sealed tightly did not give rise to microbes. Living did not come from the non-living.

Pasteur: Broth boiled and stored in flasks did not give rise to microbes, even when swan-necked tube was used to allow fresh air in but air-borne microbes could not get in. - Living did not come from non-living.

5. Cell Theory a) The smallest entity of life is the cell, anything smaller than a cell is non-living. b) All organisms consist of one or more cells c) Cells only come from pre-existing cells. 6.

7. The limit of resolution is the point of magnification in a microscope beyond which images become blurry and lose detail.

8. POWER Ocular Objective Total LOW 10 X 4 X 40 X MEDIUM 10 X 10 X 100 X HIGH 10 X 40 X 400 X

9. The total power would be 15 X times 20 X = 300 X

10. There are 10 mm in 1 centimeter. There are 1000 um in 1 mm, and there are 10, 000 um in 1 cm.

11. 4.5 mm = 4,500 um

12. FOV = 2.2 mm  2,200 um

Estimated size of specimen is : ______FOV______# of specimens that fit across

______2,200 um_____ 2.6 specimens fit across

The specimen must be approximately 846 um wide 13. The drawing magnification of the specimen is : Drawing mag. = _____Drawing size_____ Estimated actual size

Drawing mag. = 1 cm  10, 000 um (on the piece of paper) 846 um Drawing Magnification is approximately = 11.8 X

14. Proteins are made up of amino acids linked together DNA is made up of DNA nucleotides linked together.

15. The three major nutrient groups are : FATS, PROTEINS, CARBOHYDRATES

16. There are about 20 different amino acids used by the body.

17. Deoxyribolnucleic Acid

18. Each nucleotide consists of the following: a) A five carbon sugar molecule (deoxyribose) b) A phosphate group c) A nitrogenous base

19. The shape of DNA is described as being a “double helix” 20. DNA wrapped around histones forms “chromatin”

Chromosome

21. The X-shaped structures of condensed chromatin are called chromosomes.

22.a) In a normal (healthy) human diploid cell, there would be 46 chromosomes. b) In a normal (healthy) haploid cell (Gamete :egg or sperm) there would be 23.

23. A gene is a segment of DNA that codes for the synthesis of a particular protein. 24. Purines are double-ringed bases called “adenine” and “guanine”, they are two types of nitrogenous bases that form a given type of DNA nucleotide.

Pyrimidines are single-ringed bases called “cytosine” and “thymine”, these are the other 25. The four nitrogenous bases as illustrated above are: - Adenine and guanine which are double-ringed (purines) - Cytosine and thymine which are single-ringed (pyrimidines)

26. The type of bonds that form between two complimentary bases is a weak bond, called a “hydrogen bond” Hydrogen Bond

27. The complimentary strand for the following is illustrated in red. ______A C G T T T A G C C G A T T A A G A G C A T A

T G C A A A T C G G C T A A T T C T C G T A T 28. Replication is the process of making two identical molecules of DNA from one original molecule of DNA. First DNA unwinds and then unzips, then each half strand acts as a template for complimentary base pairing of complimentary DNA nucleotides. As illustrated below:

29. Transcription is the process of using a piece of DNA (gene) as a template to make a piece of mRNA, it takes place in the nucleus. This newly formed piece of mRNA will carry the code of the gene from the nucleus out to the cytoplasm.

- Translation is the process of using (decoding) the piece of mRNA to determine the specific order that a number of amino acids should link together to form a given protein.

30. The percentage of difference between the cytochrome c of a dog and the cytochrome c of a pig is a 6% difference. 31. The closest genetic relationship is seen between: Pig vs. Donkey = 5.1% difference Pig vs. Dog = 6.0% difference Horse vs. Dog = 7.7% difference

32. According to the “Case Study” the closest relationship is seen between the “Silkworm” and the “Hornworm”

33. Five things that provide support for the theory that life forms can evolve are: A) The fossil record. Ex. Ancestral horse  modern horse B) Embryological similarities. Ex. gill slits, gill pouches, tail structure C) Homologous structures. Ex. Forelimbs of bat, human, sea lion = similar anatomy. D) Vestigial structures. Ex. Human appendix, snakes hips, cave fish eyes E) Biochemical homologies. DNA, cytochrome C etc. F) Biogeographical evidence : Ostriches, Emus, Rheas, all large flightless birds; could they have derived from a common ancestor back on Pangaea

34. The three main categories of adaptations are: A) Structural : A body part/structure that helps that organism survive. Ex. A turtle’s hard shell, thorns on a rose bush B) Physiological : A biochemical mechanism in an organism that helps them survive. Ex. Toxins in a plant/chili pepper, the production of ink in a squids ink sac. C) Behavioural : A behaviour that an organism uses to help it survive. Ex. A rattle snake rattling, a tree tracking sunlight.

35. See above

36. The name for Darwin’s theory is “Natural Selection” it is also called “Survival of the Fittest”

37. Lamarck’s theory of evolution is called “Inheritance of Acquired Characteristics”

38. Natural Selection states that within a species members of that species show variation. There is also a limited amount of resources required for survival. To attain the required resources members compete against each other. The members with the best phenotypes (adaptations) will out-compete the other less-suited members. The best fit will survive and pass their genes onto form the next generation

Inheritance of Acquired Characteristics: According to Lamarck, he felt that if an organism uses a structure frequently, that structure will begin to develop more. If a structure is not being used it will diminish. Whatever the case, the change to that organism will be passed onto the offspring.

39. Charles Lyell demonstrated that the Earth is much older than many people thought and that the Earth changes over time.

- Thomas Malthus stated that offspring are being produced at a much higher rate than the normal death rate due to old age. But populations do not grow exponentially, but rather, they level off due to limited resources

- Artificial Selection – A selective breeding practice used by farmers to improve the phenotypes of their crops and livestock.

40. For natural selection to take place the following are required: a) There must be variation in a population b) There must be limited resources c) The population must be larger than the resources can support. d) There must be competition for those resources

41. The three main ways that natural selection can shift a population are: A) Stabilizing selection B) Disruptive selection C) Directional selection

42. “Industrial Melanism” is a case of natural selection documented in a species of moth called the pepper moth. Prior to the Industrial Revolution the normal phenotype (peppered) were better at camouflaging to avoid predators than the other phenotype(melanic). That was reversed during the industrial revolution; as soot covered the trees the peppered phenotype stood out and the melanic blended in better. The phenotypic ratio drastically changed over a short period of time due to natural selection.

43. Gregor Mendel is known as the “Father of Genetics”

44. A) Phentoype : The physical traits an organism possess. Ex. Brown Eyes

B) Allele: The given form of a gene. For biology 11, we say that each gene may have two forms or alleles. Ex. A gene for eye colour may have a sequence of bases that codes to make the iris brown, or it may have a different sequence of bases that may code to make the iris blue. In this case the gene for eye colour has two alleles (forms)

C) Genotype: Is the combination of alleles (forms of the gene) that an individual possesses. Each individual inherits one set of genes from their father and the other complimentary set of genes from their mother. So for a given gene, like the eye colour gene, an individual gets a pair of that gene. Sometimes the pair consist of the same two alleles for example, BB or bb; other times the individual gets two different alleles Bb.

D) Meiosis: The type of cell division that takes place in the reproductive organs to make new haploid cells (gametes –sex cells) from normal diploid body cells.

E) Homozygous: The genotype of a cell where two of the same type of allele were inherited. Ex BB or bb

F) Segregation: The separation of the two inherited alleles during the formation of the gametes. Ex. Bb  B b

G) Heterozygous: The genotype of a cell where two different types of alleles were inherited. Bb.

H) Crossover: A process that takes place during meiosis just before segregation. During crossover two homologous chromosomes (one from mom, one from dad) position themselves side-by-side, and a piece from one chromosome breaks off and moves onto the other chromosome and vice versa.

45. The two main processes that increase variation in a population of a species are: - Mutation – Makes new alleles - Sexual Reproduction – Shuffles up the alleles

46. Heterozygous Black Rabbit (Bb) X Heterozygous Black Rabbit (Bb) Gametes B b B BB Bb b Bb bb

B) Heterozygous Tall Pea Plant (Tt) X Homozygous Recessive (tt) Gametes T t t Tt tt t Tt tt 47. For 50 % of the F1 generation to have the dominant phenotype while the other 50% has the recessive phenotype. The parents must be : Bb X bb

48. A) The allelic Frequency is - "B" = 24/50 = 48% "b" = 26/50 = 52%

B) BB = 6/25 = 24% Bb = 12/25 = 48% bb= 7/25 = 28%

C)Phenotypic Ratio – BLACK – 18/25 = 72% WHITE – 7/25 = 28%

49. Genetic equilibrium is the condition in a population where the gene pool (all the genes and the relative frequency of each allele) is kept in balance, unchanged from one generation to the next to the next. The population is not evolving (changing).

To maintain this state the following conditions must be met: a) The size of the population must be very large b) There must be no new alleles introduced – no mutation c) There must be random mating – NO selective mating d) There must be NO differential migration. e) There must be equal viability (health) and fertility among all members

50A). Differential Migration is the process whereby a group of members moves out of or moves into a population, but this group that moves out/in does not have the same proportion of phenotypes that the main population possesses. Therefore there is a shift in the frequency of each allele. Example, A population of 100 squirrels has 90 Grey squirrels and 10% Red squirrels. During a fire, 10 squirrels migrate into a different part of the forest and they do not return to the original population. If the 10 that emigrated consist of 9 Grey and 1 Red, the allelic frequency is unlikely changed, but if the 10 that emigrate are 7 Red and 3 Grey, the frequency of the red allele would most likely be much lower and as a result the frequency of the Grey allele would increase.

B) Genetic drift is the shift in frequency of the alleles, by chance. If 50% of all the alleles in a population are (A) and the other 50% are (a), then the chances of the next generation’s allelic frequency being 50% : 50% should be pretty good. But there is also a chance that by chance the next generation’s allelic frequency could be 70% (a) and 30% (A). Example: get a coin and flip it 10 times, there’s a chance you should get 5 heads and 5 tales, but there is also a chance you could get 10 heads in a row. Try It!

51. Divergent evolution is change to one species in which two populations change to become different to each other. Sometimes they become so different from one another that they become two different species. Ex. Crocodiles and Alligators Convergent evolution is change to two different species, so that they resemble each other. They can never become so similar that they become one species. Ex. Tasmanian wolf and Timber wolf.

52. Adaptive radiation is a type of DIVERGENT evolution in which one species branches off to form many different but closely related species.

53. A) Species: a group of similar looking organisms that can and usually interbreed with one another to reproduce fertile healthy offspring.

B) Population: A group that belongs to a given type of species that live in the same area and breed with one another.

C) Speciation: The process by which two or more different species form from the divergent evolution of one original species.

D) Niche : The combination of an organism’s habitat and its role it plays in that habitat.

E) Analogous Structures : Structures that have similar appearance and function, but the origin (DNA code/anatomical design) of the structures is very different.

F) Homologous Structures: Structures of different organisms that look quite different and may have different functions, but they have similar origin. DNA code/anatomical design)

54. Both Gradualism and Punctuated Equilibrium are different view on trying to explain how fast evolution takes place. In Gradualism, the rate of evolution is very slow and there is not any drastic change over a short period of time. In Punctuated Equilibrium, there are long periods of unchanged (equilibrium) followed by quick burst of drastic change.