Untitled Flashcards Set

What is the difference between sister chromatids and homologous chromosomes?

Sister chromatids are identical copies of a chromosome, while homologous chromosomes are pairs of chromosomes from each parent that are similar but not identical.

How does meiosis produce four haploid gametes?

Meiosis consists of two rounds of cell division that result in four haploid gametes, each with half the number of chromosomes.

What happens during non-disjunction in Meiosis 1?

In Meiosis 1, two gametes may have an extra chromosome (n+1) and two may be missing a chromosome (n-1).

What is a Punnett square used for?

A Punnett square is used to calculate the likelihood that an individual will inherit a particular genotype or phenotype.

How can chromosome numbers vary due to non-disjunction in Meiosis 2?

In Meiosis 2, one gamete may have an extra chromosome (n+1), one may be missing a chromosome (n-1), and two gametes will be normal (n).

What are dominant and recessive traits?

Dominant traits are expressed in the phenotype even if only one copy is present, while recessive traits are expressed only when two copies are present.

What is a pedigree used for in genetics?

A pedigree is used to analyze the inheritance patterns of traits within a family across generations.

What is the significance of Hardy-Weinberg equilibrium?

Hardy-Weinberg equilibrium is a principle that states that allele and genotype frequencies will remain constant in a population if certain conditions are met, indicating no evolution.

What are the 5 assumptions of Hardy-Weinberg equilibrium?

1) No natural selection, 2) No assortative mating, 3) No genetic drift, 4) No mutations, 5) Sufficiently large population size.

How does natural selection affect allele frequencies?

Natural selection can change allele frequencies by favoring individuals with advantageous traits, thus impacting population evolution.

What is kin selection?

Kin selection is a type of natural selection that favors behaviors that improve the reproductive success of relatives.

What does direct fitness measure?

Direct fitness measures the number of offspring an individual produces that survive to reproductive age.

What distinguishes a biological species according to the biological species concept?

A biological species is defined as a group of actually or potentially interbreeding populations that are reproductively isolated from other such groups.

What are the two main types of isolating mechanisms?

Prezygotic isolating mechanisms prevent mating or fertilization, while postzygotic isolating mechanisms prevent the development of viable, fertile offspring.

What is adaptive radiation?

Adaptive radiation is the rapid evolution of a group of organisms into new species, filling different ecological niches.

How do mass extinctions relate to biodiversity?

Mass extinctions open up ecological niches, allowing for diversification and the evolution of new species in the aftermath.

What is functional redundancy in an ecosystem?

Functional redundancy refers to the phenomenon where multiple species can perform the same ecological role, enhancing ecosystem resilience.

What is the role of primary producers in an ecosystem?

Primary producers capture solar energy through photosynthesis, forming the base of the food chain and supporting all other trophic levels.

How does over-exploitation affect biodiversity?

Over-exploitation can lead to population declines, habitat destruction, and ultimately, loss of species, decreasing biodiversity.