bio lecture 19 polymerase I cell cycle mitosis

what direction do both dna polymerase III and dna polymerase I add nucelotides and remove nucleotides in

5’ to 3’ direction

which dna polymerase removes nucleotides in the 5’ to 3’ direction (primer removal)

dna polymerase I

dna polymerase III processivity (length of dna synthesized

high

dna polymerase I processivity (length of dna synthesized

low

chromatin

double stranded eukaryotic dna coiled around histones

chromatid

double stranded eukaryotic dna coiled around histones

histones are tightly packed in …

chromatids

histones are loosely packed in ….

chromatin

chromatin condense into

chromatids

chromatids relax into

chromatins

2 different forms that a chromosome can take

chromatins and chromatids

after replication, each sister chromatid has a

centromere and kinetochore

sister chromatids become highly condensed when

cell is preparing to divide

what does this represent

a chromosome

what is #1

a telomere

what is #2

a centromere

what is #3

a kinetochore

what is #4

a chromosome arm

what makes up a chromosome

chromatids

chromatid

one of two identical halves of replicated chromosomes

how many chromatids make up a pair of sister chromatids

2

centromere

region where sister chromatids are joined

chromosome arm

short vs long arm

kinetochore

proteins that bind to the centromere

what are kinetochores necessary for

sorting chromosomes

telomere

a region at the end of a chromosome

homologous chromosomes are

similar but not identical

what are these an example of

homologous chromosomes

true or false: dna replication doesn’t change chromosome number

true

how many homologous chromosomes do humans have

23

how many total chromosomes do humans have

46

what are the phases of the cell cycle

G1, S, G2, M

what phases of the cell cycle make up interphase

G1, S, G2

G1 phase

primary growth phase, usually the longest, cell becomes divided

S phase

Synthesis of dna, each chromosome replicated

what does the S phase form

sister chromatids

G2 phase

organelles replicate, proteins necessary for chromosome sorting are made

G0 phase

nondividing phase

G1 checkpoint

determines if conditions are favorable for cell division and if the dna is damaged

G2 checkpoint

checks for dna damage, determines if all the dna is replicated and monitors the levels of proteins needed for M phase`DC

G1, S, G2

interphase

start of mitosis

prophase

mitotic spindle

structure responsible for organizing and sorting chromosomes duing mitosis

prometaphase

when sister chromatids attach to the spindle

prometaphase

prophase

when sister chromatids condense and the mitotic spindle starts to form

metaphase

metaphase

sister chromatids align along the metaphase plate

anaphase

anaphase

sister chromatids separate and individual chromosomes move toward the poles a

chromosomes condense and the nucelar envelope reforms

telophase

what quickly follows mitosis and the two nuclei separate into daughter cells

cytokinesis

mitosis makes

body cells

meiosis makes

gametes (sperm and egg cells)