Ch 9 Flashcards
What is the most predominant form of cellular replication?
The most predominant form of cellular replication creates genetically identical daughter cells
What are gametes?
Cells involved in sexual reproduction that are haploid (contain one copy of each chromosome).
What are somatic cells?
Most cells in the body that are diploid (contain two copies of each chromosome, called homologous chromosomes).
What is mitosis?
A type of cell division that results in two genetically identical daughter cells and occurs in somatic cells.
What is meiosis?
A type of cell division that results in four genetically unique haploid gametes and occurs in germ cells in the gonads.
What are the roles of mitosis?
- Reproduction
- Development
- Growth
- Tissue renewal
What is a genome?
The entirety of the genetic material in a cell.
Describe the structure of a chromosome
chromosome consists of a single double-stranded DNA molecule.
Describe the genome of prokaryotes.
Prokaryotes generally contain a single circular chromosome. They may also have extrachromosomal plasmids that carry beneficial (but nonessential) genes.
Describe the genome of eukaryotes.
- multiple linear xsomes in nucleus
Genetic info is also found in mitochondria and chloroplast
What is chromatin? What is it composed of
When replication is not occurring, DNA is found in the form of chromatin. Chromatin is composed of DNA and histone proteins.
What happens to DNA during cell division?
is condensed into chromosomes.
What is the structure of a duplicated chromosome?
consists of two sister chromatids (two copies of the same DNA) joined at the centromere.
The part of the chromatid on either side of the centromere is called an arm.
What is interphase
cell is not replicating
. During interphase, cells grow and are metabolically active, fulfilling their role(s) in the organism.
What happens during the G1 phase of interphase?
- cells grow and produce cellular components.
Some cells are non-dividing and shift permanently into the G0 phase (e.g., mature nerve and muscle cells).
Some cells temporarily move into the G0 phase to perform their cellular duties before being called back into the S phase
What happens during the S phase of interphase?
Dna replication