Topic 11

Question 1

Which of the following causes evolutionary change, individuals mating with phenotypically similar mates?

Answer 1

Nonrandom Mating

Question 2

Which of the following are not agents of evolutionary change?

Gene flow

Mutations

Random mating

Genetic Drift

Selection

Answer 2

random mating

Question 3

Fitness is defined in a particular population would be considered of which of the following?

Answer 3

The number of surviving offspring left in the next generation

Question 4

Founder effects and bottlenecks are examples of what?

Answer 4

forms of genetic drift

Question 5

In order for evolution to occur by selection which of the following must take place?

Phenotypic variation must exist among individuals

Variation among individuals must result in differences in the number of offspring surviving in the next generation

Phenotypic variation must have a genetic basis

All of the above

Answer 5

all of the above

Question 6

Which of the following causes evolutionary change, by the random fluctuation in allele frequencies in populations over time by change?

Answer 6

genetic drift

Question 7

Which of the following causes evolutionary change, due to the movement of certain alleles into or out of one population to another?

Answer 7

gene flow

Question 8

The Hardy-Weinberg principle states which of the following?

Answer 8

Genotype proportions do not change but remain constant, under certain assumptions

Question 9

Allele frequencies in population genetics is measuring what?

Answer 9

The occurrence of individual alleles expressed in an entire population

Question 10

For natural selection to result in evolutionary change which of the following must occur?

reproductive success of different phenotypes must differ

variation must exist in a population

variation must be inherited from one generation to the next

All of the choices are correct

Answer 10

all of these choices are correct

Question 11

Define and list the difference between Lamarch’s and Darwin’s Theory of Evolution/Natural Selection?

Answer 11

Darwin’s theory of natural selection – states that evolutionary changes occur when certain individuals produce more surviving offspring’s due to their advantageous characteristics.

Lamarck’s theory -Evolution occurred by the inheritance of acquired characteristics, that organisms acquire changes during their lives that can be passed on to their offspring’s, allows evolutionary adaptations.

Question 12

Define and list the conditions needing to be met for the Hardy-Weinberg Principle to be at equilibrium, and how does this help us to understand evolution?

Answer 12

1. no mutations take place,
2. no genes are transferred to or from other sources (no immigration or emigration takes place),
3. Mating is random ( individuals do not choose mates based on their phenotype or genotype),
4. Population size is very large,
5. no selection occurs.

genotypes’ proportions do not change, and remain constant from generation to generation, and why genetic variation persists, as long as the previous assumptions are met

Question 13

Jean-Baptiste Lamarch Theory,

Answer 13

Evolution occurred by the inheritance of acquired characteristics, that organisms acquire changes during their lives that can be passed on to their offspring’s, allows evolutionary adaptations

Question 14

Charles Darwin Theory,

Answer 14

states that evolutionary changes occur when certain individuals produce more surviving offspring’s due to their advantageous characteristics

Question 15

Hardy-Weinberg Principle

Answer 15

genotypes’ proportions do not change, and remain constant from generation to generation, and why genetic variation persists, as long as the following assumptions are met:
no mutations take place,
no genes are transferred to or from other sources (no immigration or emigration takes place), Mating is random (individuals do not choose mates based on their phenotype or genotype), Population size is very large, no selection occurs.

Question 16

Genetic Variation,

Answer 16

refers to the different alleles of genes found within individuals of a population.

Question 17

Allele,

Answer 17

one of two or more alternative states of a gene

Question 18

Phenotype,

Answer 18

the realized expression of the genotype; the physical appearance or function expression of a trait

Question 19

Genotype,

Answer 19

is the genetic constitution underlaying a single trait or set of traits in an individual.

Question 20

Allele Frequency,

Answer 20

is the measure of the occurrence of each individual allele in a population, expressed as proportion of the entire population, from one generation to the next generation. Allele frequencies can change when mutations, changing of one allele for another, or gene migration brings alleles into a population.

Question 21

Biological concept of species,

Answer 21

is that each species exchanges genes with other members of its species.

says that a species is composed of populations whose members mate with each other and produce fertile offspring

Question 22

Reproductive isolation,

Answer 22

Pre-Zygotic Reproductive barriers

Ecological Isolation – Species occur in the same area, but they occupy different habitats and rarely encounter each other.

Behavior Isolation – Species mating behavior/rituals differ preventing their mating.

Temporal Isolation – Species reproduce in different seasons or at different times of the day.

Mechanical Isolation – Structural differences between species prevent mating.

Prevention of Gamete fusion – Gametes of one species function poorly with the gametes of another species or within the reproductive tract of another species.

Post-Zygotic Reproductive barriers

Hybrid inviability or infertility or Hybrid breakdown – Hybrid embryos do not develop properly, hybrid adults do not survive in nature, or hybrid adults are sterile or have reduced fertility

Question 23

Speciation,

Answer 23

Speciation is the process by which new and distinct species are formed in the course of evolution. A species is a group of organisms that can interbreed and produce fertile offspring. Speciation occurs when groups within a species become reproductively isolated and diverge

Question 24

Ecological Isolation,

Answer 24

Species occur in the same area, but they occupy different habitats and rarely encounter each other

Question 25

Behavior Isolation,

Answer 25

Species mating behavior/rituals differ preventing their mating.

Question 26

Temporal Isolation,

Answer 26

Species reproduce in different seasons or at different times of the day

Question 27

Mechanical Isolation,

Answer 27

Structural differences between species prevent mating

Question 28

Gamete Fusion,

Answer 28

Prevention of Gamete fusion – Gametes of one species function poorly with the gametes of another species or within the reproductive tract of another species

Question 29

Hybrid inviability/Infertility,

Answer 29

Hybrid embryos do not develop properly, hybrid adults do not survive in nature, or hybrid adults are sterile or have reduced fertility

Question 30

Taxonomy,

Answer 30

is the branch of science that deals with the classification of organisms.

Specific scientific name are given to each species, called binomial name, consisting of a genus and species.
Human: Genus = Homo; species sapiens.
Dogs: Genus = Canine; Species = Lupus.

Question 31

Cladistics,

Answer 31

is a type of taxonomic systematists, that classifies species based on similarities that arise most recently, and not inherited from the most recent common ancestor of the group.

In this approach, only shared derived characters are considered informative in determining evolution relationships.

Question 32

Phylogenetics,

Answer 32

uses modern genetics and biochemical analyses, reveals relatedness among diverse organisms, looking at the changes in genetics and modifications in amino acid sequences in genes.

Question 33

Hardy-Weinberg Principle/Equilibrium,

Answer 33

genotypes’ proportions do not change, and remain constant from generation to generation, and why genetic variation persists, as long as the following assumptions are met:
no mutations take place,
no genes are transferred to or from other sources (no immigration or emigration takes place),
Mating is random ( individuals do not choose mates based on their phenotype or genotype),
Population size is very large,
no selection occurs.

Question 34

Frequency-dependent Selection,

Answer 34

in some circumstances, the fitness of a phenotype depends on its frequency within the population, and this type of selection favors certain phenotypes depending on how commonly or uncommonly they occur, and can be positive or negatively impacting

Question 35

Stabilizing Selection

Answer 35

is a type of selection that acts to eliminate both extremes from an array of phenotypes, and results is to increase the frequency of the already common intermediate.