lab 4: evolution

Question 1

evolution

Answer 1

-change in heritable characteristics of a population over successive generations

Question 2

scientific theory

Answer 2

-a well-supported testable explanation of phenomena that have occurred in the natural world

Question 3

natural selection

Answer 3

-the superior survival or reproduction of some (genetic) variants compared to others, under the prevailing environmental conditions
-heritable traits that help organisms survive & reproduce become more common in a population over time
-fit individuals produce more offspring bc traits are better adapted survival & reproduction
-the frequency of these traits will increase in population

Question 4

adaptation

Answer 4

a biological mechanism by which organisms adjust to new environments or to changes in their current environment

Question 5

fitness

Answer 5

-an organisms tendency to produce more offspring than competing individuals, therefore contribute more genes to the next generation
-describes the capability of an individual of certain genotype to reproduce

Question 6

mutation

Answer 6

-a spontaneous change in the gene frequency that takes place in a population & occurs at a low rate
-occurs randomly

Question 7

migration

Answer 7

-a local change in gene frequency when an individual moves from one population to another & then interbreeds
-occurs randomly

Question 8

genetic drift

Answer 8

-a change that takes place from one generation to another by a process of pure chance
-happens randomly

Question 9

key elements of the concept of natural selection

Answer 9

-population evolve, organisms do not
-individual variation
-heritable characteristics
-survival of the fittest

Question 10

population

Answer 10

-the collection of interbreeding organisms of a particular species living in a given geographic area
-not a group of identical individuals

Question 11

selection pressures

Answer 11

-factors such as temperature & predation that affect organisms & result in selective reproduction of genotypes
-acting on phenotype & associated genotype
-positive selective: favors a characteristic that increases fitness of individuals
-negative selection: selection against a characteristic

Question 12

Hardy-Weinberg assumptions

Answer 12

-the population is large enough to overcome random events
-choice of mates is random
-mutation does not occur
-individuals do not migrate into or out of the population
-there is no selection pressure

Question 13

equation that represents alleles

Answer 13

p= dominant
q= recessive
p+q=1

Question 14

equation that represents genotype

Answer 14

-p^2 +2pq + q^2

Question 15

the volvocale order

Answer 15

1. chlamydomonas
2. gonium
3. pandorina
4. eudorina
5. volvox