Unit 5 Flashcards
waht does dna stand for
deoxyribonucleic acid
three enzymes involved in dna replication
dna polymerse, helicase, dna ligase
what stage is dna replicated for cell division
interphase
why must dna be replicated
so each new cell has a complete set of dna
match
adenine:
cytosine:
thymine
guanine
write a sequence of dna
ttaacgc
main events of interphase
growth, dna replication
main events of prophase
spindle fibers grow from chromosomes, chromosomes condense
main events of metaphase
csomes line in middle by spindle fibers
main events of anaphase
csomes split into sister chromatids, spindle fibers pull apart chromatids
main events of telophase
chromatids converge on each side, new nuclei form
programmed cell death is called
apoptosis
three characteristics of cancer cells
poorly differentiated, abnormal membrane, grow abnormally
why do cancer cells have tumours
uncontrolled cell division, lack of protiens
three cancer treatments
surgery, chemotherapy, radiation
risk factors for developing cancer
age, lifestyle,family history
primary cause of cancer
dna changes, cells divide uncontrollably
compare somatic and gametic cells
somatic: body cells
gametic: sex cells
what does it mean if a cell is a diploid
contains homologous pair
what does it mean if a cell is a haploid
contains one copy of chromosomes
haploid have what of the chromosomes of a diploid
half
during meiosis what events introduce genetic variation
crossing over and law of independent assortment
main events of prophase 1
csomes pair up and form tetrads
metaphase one
csomes align in middle
anaphase one
csomes pull apart, chromatids remain attached
telophase one
cell divids in two
prophase two
csomes contains two copies of dna
metaphase two
csomes line in equator
anaphase two
sister chromatids pull apart
telophase two
four daughter cells form
why must sperm and egg cells be haploids
to avoid genetic problems
how are homologous chromosomes different from sister chromatids
sisters are identical and homologous csomes have two different csomes
what is a karyotype
an individual complete set of csomes
what is nondisjunction
failure of separation
what is an abnormality produced by nondisjunction
down sundrome
