Quiz #9 Flashcards
when are zygotes made
when sperm cell fertilizes egg cell
what are gametes and what are they produced by?
they are human reproductive cells and they are produced by meiosis
what is one gametes equivalent to
23 chromosomes
what do mitosis cells mean
the ending cells are identical to the original
are mitosis cells diploid or haploid?
diploid
what do meiosis cells mean
ending cells are not identical to original
are meiosis cells diploid or haploid
haploid
what is spermatocyte
the cell that gives rise to sperm - in males
what is oocyte
egg cell produced in female fetus - in females
what is crossing over
the exchange of corresponding segments of DNA between 2 homologous chromosomes
what is independent assortment
random lining up of homologous pairs at middle of cell
what is a karyotype
a picture of chromosomes organized by size and shape
what is the process of a karyotype
1) cells will be taken from blood or skin
2) those cells are put in hypotonic solution to burn red cells and only white cells remain
3) centrifuged - chromosomes stained with giemsa to show unique bands
4) computer organizes chromosomes based on size and shape
5) picture is created to show chromosomes
what is translocation
when 2 chromosomes swap segments
what is tetrad
a pair of homologous sister chromatids
what is nondisjunction
an error in meiosis so chromosomes fail to separate
how does the image look like in metacentric
top circles are the same size as the bottom ones
how does the image look like in submeta
top circles are slightly smaller than the bottom ones
how does the image look like in acrocentric
top circles are a lot smaller than the bottom ones
what are the characters of trisomy 21
- distinct facial features
- short stature
- heart defect
- irregular teeth
- short life
what is the abnormality if XXY and what is the cause of it
kline felter. cause is nondisjunction of sperm and egg formation
what is the abnormality if X and what is the cause
turner. cause is nondisjunction of sperm and egg formation
what is the abnormality if XXX and what is the cause
no syndrome. cause is nondisjunction in sperm and egg formation
what is the abnormality if XYY and what is the cause
no syndrome. cause is nondisjunction in sperm and egg formation
what are the roles of cell division
single celled organisms and multi celled organisms
what is the process of binary fission
1) copy dna
2) cell grows or elongates
3) plasma membrane grows inward
why do cells divide
1) reproduction of organisms
2) growth
3) replace worn out or damaged cells
4) healing wounds
what is the relationship between chromatin, chromosomes, and siter chromatids
chromatin condenses to become chromosomes when cells divide which eventually split into 2 identical chromatids called sister chromatids
