Full Chapter 12 Flashcards
Condensed chromatin structure formed when cells replicate.
Chromosomes
One half of a chromosome. Two sister chromatids are joined by a centromere to form a chromosome.
Chromatid
One of two chromosomes that are genetically identical and held together at the centromere.
Sister chromatids
One of the different forms of the same gene
Alleles
Governs expression of a trait
Gene
X or Y chromosome; determines genetic sex (Female = XX; Male = XY)
Sex chromosomes
Chromosomes with the same gene sequence
Homologous chromosomes
Cells with two pairs of homologous chromosomes. The ——— number in humans is 46, or 23 pairs.
Diploid cell
Cell with half the number of chromosomes as diploid. Human gametes, or reproductive cells (egg and sperm cells), are ———. (The ——— number of chromosomes in a species is designated as n. In humans, n = 23, and a diploid cell has 2n chromosomes (2n = 46).)
Haploid cell
An individuals complete set of chromosomes.
Karyotype
The cell grows quickly during this phase, making new cell molecules (except DNA).
G1 phase
The DNA in the chromatin replicates to create an identical copy of DNA. These two identical chromosomes, called sister chromatids are joined at the centromere.
S phase
This second growth stage lets the cell rebuild its reserves of energy to prepare for division. As well, the cell manufactures proteins and other molecules to make structures required for division of the nucleus and cell.
G2 phase
Refers to a body cell
Somatic cell
Sex cell (egg or sperm)
Germ cell
Growth phase; includes G1, S phase, and G2
Interphase
It is a continuous process that involves two stages: mitosis and cytokinesis
Division Stage
Division of the cell’s nucleus where the daughter cells receive the exact number of chromosomes and genetic makeup as the parent cell.
Mitosis
Separation of the cytoplasm and the formation of two new daughter cells; occurs after telophase of mitosis
Cytokinesis
Chromosome other than sex chromosome
Autosome
A membrane that encloses the nucleus
Nuclear membrane
Is a barrel-shaped cell structure involved in the organization of the mitotic spindle and in the completion of cytokinesis
Centrioles
One of a network of fibres that forms the spindle apparatus during cell division (mitosis); made of mictotubules, hollow tubes of protein that facilitate movement of chromosomes within a cell.
Spindle fibres
Is a region of DNA typically found near the middle of a chromosome where two identical sister chromatids come closest in contact.
Centromere
A plasma membrane invagination at the cell division site.
Cleavage furrow
A eukaryotic cell formed by a fertilization event between two gametes. (Sexual reproduction requires the fusion of a male and a female reproductive cell to produce a ——.
A —— receives half its genetic material from the female parent and the other half from a male parent.
Zygote
- a advanced cell
- a more complex cell with a true nucleus and membrane bound organelles such as E.R., ribosomes, Golgi apparatus, etc…
- ex. These are in cineplex organisms such as humans and other animals. (Ex: blood cells, liver cells, muscle cells, nerve cells)
Eukaryotic
- primitive cell
- a simple cell with NO true nucleus
- ex: simple organisms have these cells. (Bacteria, amoeba, paramecium, single cell organisms)
Prokaryotic