Ch.16- 60 Evan Kaplan biology Msstate

Cell division

The reproduction of cells

Where does new cells come from

Pre-existing cells

Cell cycle

Series of events that leads to cell division

What is Cytogenetics

Field of genetics that involves the microscopic examination of chromosomes

What happens when a cell prepares to divide?

The chromosomes become more tightly compacted

How many pairs of chromosomes do humans have

23

How many chromosomes do humans have

46

How are chromosomes(autosomes) numbered

Based on size, larger chromosomes have smaller numbers and vice versa

What is a diploid

When the cells of an organism carry 2 sets of chromosomes

What are gametes and are they diploids

Sperm and egg cells, they are haploids (1 set of chromosomes)

What are the phases of the cell cycle

G1(first gap), S(synthesis of DNA), G2(2nd gap), M phase(mitosis and cytokenisis)

G1 phase

a period in a cell’s life when it may become committed to divide

S phase

each chromosome is replicated to form a pair of sister chromatids, a cell has twice as many chromatids as the number of chromosomes in the G1 phase

G2 phase

a cell synthesizes the proteins necessary for chromosome sorting and cell division

M phase

Mitosis, divide one cell nucleus into two nuclei, distributing the duplicated chromosomes so that each daughter cell receives the same complement of chromosomes splitting those 92 chromatids in g2 into 46 and sharing amongst the 2 daughter cells, followed by cytokenises

Cytokenises

The division of the cytoplasm to produce 2 distinct daughter cells

Approximately how long is each phase of the cell cycle

G1:11 hrs, S phase: 8 hours, G2: 4 hrs, M phase: hour

What are cyclins and cyclin dependent kinases

Proteins responsible for advancing a cell through the phases of the cell cycle.

Mitotic spindle

Responsible for organizing and sorting chromosomes during cell division