Chapter 1

Question 1

Define Zoology

Answer 1

Scientific study of animal life

Question 2

What are the major characteristics of animals

Answer 2

Multi cellularity, coelom, spiral cleavage, vertebrae homethermy

Question 3

What are the essential characteristics of science

Answer 3

• science is guided by law
• science has to be explained by reference to natural law
• science is testable against the observable world
• the conclusions of science are tentative
• science is falsifiable

Question 4

What are the components of the science method?

Answer 4

Observation
Question
Hypothesis
Empirical Test
Conclusions
Publications

Question 5

How is the term theory used differently in science?

Answer 5

In everyday, theory means speculation in science it means explanation of nature or predictions ( observation)

Question 6

How are comparative methods different from experimental methods?

Answer 6

In comparative you investigate where as experimental method has three steps

• predicting
• make treatment
• compare results

Question 7

Who were some of the earliest contributors to evolutionary thought?

Answer 7

Charles Darwin , Alfred Wallace

–Early Greek philosophers Xenophanes, Empedocles, and Aristotle

Question 8

How does Darwins Theory of of natural selection work?

Answer 8

Variation. Organisms (within populations) exhibit individual variation in appearance and behavior. …
Inheritance. Some traits are consistently passed on from parent to offspring. …
High rate of population growth. …
Differential survival and reproduction.

Question 9

Define Gene

Answer 9

segment of DNA that makes a protein which affects a certain trait

Question 10

Define Allele

Answer 10

Gene Variant

Question 11

Define Dominant

Answer 11

expressed trait whenever at least one copy of allele is present

Question 12

Define recessive

Answer 12

expressed trait only when both copies are present

Question 13

Define homozygous

Answer 13

possessing two identical alleles

Question 14

Define Heterzygous

Answer 14

possessing different alleles

Question 15

Define genotype

Answer 15

allelic combination for a trait

Question 16

Define phenotype

Answer 16

expressed trait, what is seen

Question 17

What is a gene pool

Answer 17

All alleles of all genes that exist in a population

Question 18

How are genotype frequencies calculated?

Answer 18

by expanding the binomial (p - q)2 where p and q are allele frequencies for the dominant (p) and recessive traits (q)
•p2 + 2pq + q2 = 1

Question 19

What is Hardy-Weinberg Equilibrium (HWE)?

Answer 19

–Genotypic frequencies remain in balance unless disturbed
–Allows for rare traits caused by recessive alleles to persist
–In natural populations, Hardy-Weinberg equilibrium is disturbed by 1 or more of 5 factors
•Mutation
•Genetic Drift
•Nonrandom Mating
•Migration
•Natural Selection

Question 20

Describe how HWE is upset by the following process:

Mutation

Answer 20

–Introduces new alleles, increasing genetic diversity

–Only a small change in allele frequency

Question 21

Describe how HWE is upset by the following process:

Genetic Drift

Answer 21

Chance fluctuation from generation to generation, including loss of alleles
–The smaller the population, the greater the effect of drift
–Bottlenecks
•Large reduction in population size leading to increased significance of genetic drift

Question 22

Describe how HWE is upset by the following process:

Non random mating

Answer 22

Mating that has not occurred due to chance
–Courtship displays, territories, pecking order, etc.
–Can lead to a host of phenotypes that should be selected against

Question 23

Describe how HWE is upset by the following process:

Migration

Answer 23

Prevents different populations from diverging
–If a large species is divided into many small populations
•Genetic drift and selection acting separately in the different populations can produce evolutionary divergence among them
•Small amount of migration each generation prevents the different populations from becoming too distinct genetically

Question 24

Describe how HWE is upset by the following process:

Natural Selection

Answer 24

–Stabilizing selection
•Selects against extreme phenotypes
–Directional selection
•Phenotypic character shifts in one direction
–Disruptive selection
•Selects against average phenotypes

Question 25

What are the two possible fates of a species?

Answer 25

Extinction (loss of all populations)

–Speciation (splitting of populations into new forms)

Question 26

What is a mass extinction?

Answer 26

–Periodic events where huge numbers of taxa go extinct