Chapter four, Test one Flashcards
what is the chromosome theory of inheritance
the idea that chromosomes are the carriers of genes
what are chromosomes
the self-replicating DNA/Protein complexes in the nucleus that contain genes
what is mitosis
the process of division that produces daughter cells that are genetically identical to each other and to the parent cell
what is meiosis
produce gametes
1st division: pairs of homologous chromosomes segregate into two different daughter cells
2nd division: chromatids of each homolog segregate into two different daughter cells
what is the n in meiosis one
2 n diploid
what is the n in meiosis two
1 n haploid
what is a haploid
cells carrying only one single set of chromosomes
what is a diploid
cells carrying two matching sets
if 2n=46 in humans what is n
23
what does n=23 represent in human chromosomes
23 pairs of chromosomes
what are sister chromatids
the two identical copies of a chromosome that exist immediately after DNA replication
how are sister chromatids held together
cohesions
what is a centromere
specific location where sister chromatids are held together
does each sister chromatid have its own centromere
yes
what is metacentric
centromere in center
acrocentric
centromere close to one end
what is telocentric
centromere is located at terminal end of chromosome
chromosomes are found in what two varieties
euchromatin and heterochromatin
what does euchromatin mean
true, normal chromatin
what does heterochromatin mean
different chromatin
what are satellites in chromosomes
the nucleolar organizer region (nucleolus), the site of ribosomal RNA synthesis
what are homologous chromosomes
2 sister chromosomes that mate in size and shape
how many chromosomes in humans are autosomes
44
what genotype is klinefelter syndrome
xxy
what genotype is turner syndrome
xo
what is the primary determination of maleness in humans
SRY gene on y chromosome
what genes are found on both the x and y chromosome
PARs 1 and 2, at the ends of the chromosome
where is the SRY gene found
on MSY gene region
what is the function of the SRY gene
activates testes development
secrete hormone that triggers development of male sex organs
what is gametogenesis
gamete formation
what is the names of eggs in female reproduction
oogonia, primary oocyte, first polar body/ secondary oocyte, ovum
oogonia go through what process to produce a primary oocyte
mitosis
primary oocyte goes through what process to produce a primary body and a secondary oocyte
meiosis one
meiosis one and meiosis two in oogenesis is called
asymmetrical division
the secondary oocyte goes through what process to produce another polar body and ovum
meiosis two
is an ovum a haploid or diploid
haploid
how many chromosomes does an ovum carry
22 autosomes and one X chromosome
first meiosis division occurs when in females
at puberty
what cycle does a oocyte complete before being fertilized
meiosis one and up to metaphase two
when does an oocyte go all the way through meiosis two
when egg is fertilized
what is the production of sperm
spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids, sperm
are primary spermatocytes haploid or diploid
diploid
are sperm or spermatids haploid or diploid
haploid
