bio exam 3 cell division and dna replication

mitosis

distribution of chromosomes

cell division process

1. copy the DNA

2. separate

3. physical cell will divide

chromosomes

mix of DNA and protein=chromatin

heterochromatin

tightly compacted , little to no gene expression

eurochromatin

loosely compacted, lots of gene expression

G0

cells stop dividing

G2

• growth

• checks errors of dna replication

• prepares for mitosis

S phase

dna and chromosome replication

M phase

• condensing of chromosomes

• cell division

G1

• growth

• organelles replicate

• protein synthesis

homologous chromosome pair

same set of genes but different alleles

non homologous chromosome pair

different set of genes

sister chromatid pair

identical alleles

haploid number

same as the number of chromosome types

diploid

two of each type of chromosome

total chromosome number

multiply the haploid by the ploidy level

sister chromatids

dna ligase

catalyzes phosphodiester linkages to fill gaps in the sugar- phosphate backbone

nucleic acid synthesis

only occurs in the 5 prime to 3 prime, leading strand

leading strand

newly synthesized dna that leads into the replication fork

primase

primes bare dna for synthesis by adding a little bit of rna

replication bubble

the oval shape that is a result of helicase opening up the helix

dna helicase

breaks hydrogen bonds to open the helix and create single strand dna

dna nuclease

removal of nucleotides on the damaged strand

dna polymerase

addition of new nucleotides

binary fission

a type of asexual reproduction used by prokaryotes and some single cell eukaryotes

binary fission 2

parent cell replicates its genetic material and divides into two identical daughter cells

origin of replication (ORI)

nucleotide sequence on a chromosome where dna replication begins

cytokinesis

final process of cell division, the cytoplasm of a cell divides into two identical daughter cells

human chromosome number

46, 23 pairs