Mitosis, Meiosis, and Genetics

Flashcards covering the key concepts of mitosis, meiosis, genetic variation, blood typing, and behavior types.

What occurs during mitosis?

One parent cell divides equally to produce two genetically identical daughter cells.

What is the purpose of mitosis in multicellular eukaryotes?

Mitosis is used for growth, cell replacement, and tissue repair.

What happens during prophase of mitosis?

Chromosomes coil up and condense; the nuclear membrane disappears.

What is metaphase in the cell cycle?

Chromosomes line up at the center of the cell, attached to spindle fibers.

In anaphase, what occurs to the chromosomes?

The centromeres split, and the chromatids move apart towards the poles.

What is the result of telophase in mitosis?

The formation of new daughter cells following nuclear division.

Define cytokinesis. Is it part of mitosis?

Cytokinesis is the division of the cytoplasm that occurs simultaneously with telophase.

What is synapsis in prophase I of meiosis?

The close pairing of homologous chromosomes allowing for crossing over.

What is crossing over and why is it important?

It's the exchange of genetic material between homologous pairs, creating genetic diversity.

Explain the Law of Independent Assortment.

Homologous pairs of chromosomes arrange independently during metaphase I.

What is nondisjunction?

A failure of chromosomes to separate properly during anaphase I or II.

What happens to a gamete that experiences nondisjunction?

It results in a gamete with an incorrect chromosome number.

What is the purpose of the Polymerase Chain Reaction (PCR)?

To amplify a specific segment of DNA for analysis.

List the ingredients needed for a PCR cycle.

DNA sample, nucleotides, DNA polymerase, and primers.

What are the three possible genotypes from the PCR result for the PTC tasting gene?

Homozygous recessive (one piece of DNA), homozygous dominant (two pieces of DNA), heterozygous (three pieces of DNA).

Differentiate between genes and alleles.

Genes are units of heredity; alleles are different versions of a gene.

What is the definition of phenotype?

The physical appearance or behavior of an individual.

What blood type is known as the universal recipient?

Type AB blood.

Which blood type is considered the universal donor?

Type O blood.

What is the significance of antigens and antibodies in blood typing?

Antigens are on RBCs; antibodies are in plasma; they determine compatibility.

What does a positive taxic response indicate?

Movement toward a stimulus.

What is meant by innate behavior?

Default behavior due to genetics, performed consistently every time.

How does learned behavior differ from innate behavior?

Learned behavior changes over time due to experience.

What is natural selection?

The process where organisms better adapted to their environment tend to survive and produce more offspring.