BIO exam 2024 questions and answers

What does genome size indicate about gene number and organism complexity?

Genome size does not reliably reflect gene number or organism complexity due to the presence of non-coding DNA.

What are two causes of genome size variation among organisms?

1. Accumulation of transposable elements; 2. Polyploidy.

How can sequencing mouse genomes benefit human health?

It helps identify genes involved in diseases, leading to better understanding and treatment options.

Why is the mouse a good model system for human health research?

Mice share a high percentage of genes with humans and can be genetically modified to mimic human diseases.

What process is depicted in the tree with RNASE1 and RNASE1B?

Gene duplication.

What is one advantage of gene duplication?

Increases the potential for functional innovation.

How do synonymous and non-synonymous variations differ in impact?

Synonymous mutations do not change amino acid sequences, while non-synonymous mutations can lead to functional changes.

Which advantages are associated with upright (bipedal) posture?

Liberation of hands, more efficient long-distance running, improved general visibility.

What is one line of evidence for evolution based on molecular biology?

Humans and chimpanzees share about 98-99% of their DNA, indicating a recent common ancestor.

What concept suggests that not all individuals survive due to competition for resources?

Struggle for existence.

What is 'natural selection'?

Process by which individuals with favorable traits survive and reproduce more.

Define 'fitness' in an evolutionary context.

An organism's ability to survive and reproduce in its environment.

What metric measures genetic differentiation among populations?

FST.

How can heterozygosity reflect a population's adaptive potential?

It indicates the range of alleles available for natural selection to act upon.

What is genetic drift?

A non-adaptive change in allele frequencies due to random sampling effects.

What does it mean if a population is NOT in Hardy-Weinberg equilibrium?

The population is undergoing evolutionary changes due to selection, mutation, migration, or genetic drift.

What is a genetic bottleneck?

A sharp reduction in population size leading to decreased genetic diversity.

What is inbreeding depression?

Reduced fitness resulting from mating between closely related individuals.

What does a phylogenetic tree illustrate?

The evolutionary relationships among organisms and their common ancestors.

What is 'monophyletic' in terms of phylogenetics?

A group that includes a common ancestor and all of its descendants.

What is homoplasy in the context of phylogenetic trees?

Similar traits arising independently rather than from a common ancestor.

What is the Biological Species Concept (BSC)?

A group of organisms that can interbreed and produce fertile offspring while remaining reproductively isolated from other groups.

What is kin selection?

A form of natural selection where individuals help relatives to increase the survival of shared genes.

What is reciprocal altruism?

Helping others with the expectation of receiving help in return later.

How does Hamilton's rule explain altruism?

It states that altruism evolves when the genetic benefits to relatives outweigh the costs to the altruist.

What is niche construction?

The process by which organisms modify their environment, influencing both their own and other species' evolution.

What is eco-evolutionary dynamics?

The interaction between ecological and evolutionary processes.

What is the importance of feedback in eco-evolutionary dynamics?

Ecological changes caused by evolution influence further evolutionary processes.