Biology Exam Review Flashcards

Question

What is sexual selection?

Answer 1

Favors selection of any trait that influences mating success of an individual.

Answer 2

males compete to be chosen by females, females choose mates by physical or behavioral features (bright coloration or songs).

Answer 3

Male to male competition, males compete amongst themselves. | Example, best fighting style, largest body size.

Answer 4

Morphological differences between males and females of the same.

Answer 5

The frequency of the allele compared to the total alleles found in that population.

Answer 6

Allele frequency will not change from generation to generation as long as 1. The population size remains large 2. Mating opportunities are equal 3. No mutations occur 4. No migrations occur 5. No natural selection occurs. (All individuals have an equal chance of reproducing)

Answer 7

When there are changes in allele frequency due to chance An example is when a natural disaster happens - the survivors don't survive because they were suited for the environment better, but rather because they were lucky. The alleles that are present in the survivors are only a (random) sample of those of the original population.

Answer 8

Genetic drift tends to fix alleles because they are the only allele left in the population meaning allele frequency is 100 percent. Although genetic drift doesn't have to fix alleles. Genetic drift also reduces genetic diversity.

Answer 9

A dramatic, often temporary, reduction in population size. Only a small sample of alleles survives to establish the new population. The surviving individuals often do not reflect the allele make up of the original population and due to that genetic drift happens.

Answer 10

Founder effect is when a small number of individuals isolate themselves from their original population and establish a new one. The genetic variation will not be the same as the original population.

Answer 11

Gene flow is the movement of alleles from one population to another by permanent migration or mating between populations without permanent migration. Genetic information is shared between populations. The difference between gene flow and genetic drift is that gene flow reduces the differences between populations because new alleles may be introduced to one population and alleles may be lost from another population.

Answer 12

Species biologically is a group of similar individuals that are capable of interbreeding that produce fertile offspring.

Answer 13

They are members of interbreeding groups or populations that are reproductively isolated from other groups and evolve independently

Answer 14

It's the process by which new biological species arise.

Answer 15

Any behavioral, structural or biochemical trait that prevents individuals from reproducing successfully together. Some are due to the traits of the organism Some are due to environmental circumstances

Answer 16

Allopatric speciation is when populations of a species become geographically isolated. Often a physical barrier between two populations.

Answer 17

Its the evolution of populations within the same geographic area into separate species. Gene flow is reduced between populations.

Answer 18

Adaptive radiation is the possible result of allopatric or sympatric speciation. It's when a single species evolve into a number of distinct/closely related species in one speciation event. Each new species fills a different ecological niche Usually occurs when a variety of new resources becomes available. Increases biodiversity.