meiosis terminology Flashcards
What is a chromosome?
A threadlike structure made of DNA and protein that carries genetic information.
What is a chromatid?
One of the two identical strands of a replicated chromosome.
What is a centromere?
The region where two chromatids are held together.
What are homologous chromosomes?
A pair of chromosomes with the same size, shape, and genes at the same position.
What is a bivalent?
A pair of homologous chromosomes that are physically connected during crossing over.
What is an unreplicated chromosome?
A chromosome with a single double-stranded DNA molecule
What is a replicated chromosome?
A chromosome with two identical double-stranded DNA molecules.
What happens during interphase?
DNA replication occurs before cell division.
What is the difference between diploid and haploid cells?
Diploid cells (2n) have two sets of chromosomes, while haploid cells (n) have one set.
What is a gene?
A segment of DNA that codes for a specific characteristic.
What is a centrosome?
An organelle in animal cells that contains two centrioles.
What is a centriole?
A structure that helps in cell division by moving to opposite ends of the cell.
What is crossing over?
The exchange of genetic material between homologous chromosomes during Prophase I of meiosis.
What is a chiasma?
The point where two chromatids overlap during crossing over.
What is a karyotype?
A picture showing the number, shape, and arrangement of chromosomes in a cell.
What is the difference between autosomes and gonosomes?
Autosomes are the first 22 chromosome pairs, while gonosomes (sex chromosomes) determine gender (XX or XY).
How do somatic cells and sex cells differ?
Somatic cells (body cells) are diploid and produced by mitosis, while sex cells (gametes) are haploid and produced by meiosis.
What is nondisjunction?
When homologous chromosomes fail to separate during meiosis.
What is the difference between karyokinesis and cytokinesis?
Karyokinesis is the division of the nucleus, while cytokinesis is the division of the cytoplasm.
