review Flashcards
How do you identify a chromosome?
size and length. banding pattern, position of the centromere
What is the process by which prokaryotic cells divide?
binary fission
what is the difference between mitosis and meioisis
Mitosis creates two identical cells, meiosis makes 4 unique cells
What phase of mitosis is characterized by the splitting o hromosomes and their movement to opposite sides of the cell?
anaphase
define gene
DNA that codes proteins (RNA)
define allele
1 of 2 or more alternative forms of a gene in the same position on a chromosome
what is the longest stage of the cell cycle?
interphase
what are the stages of a cell cycle?
G1 phase, S phase (synthesis), G2 (interphase) and M (mitosis, cytokinesis)
what happens during Cytokinesis
cytoplasm divides, forming 2 daughter cells
G Zero is what?
the non-dividing stage of the cell cycle
trisomy 21 is:
a genetic abnormality that leads to down syndrome
Huntington’s disease is caused by:
a dominant allele
Marfan syndrome is characterized by:
connective tissue defects
A person with AO blood has what phenotype?`
Type A
What is the difference between genotype and phenotype?
G-genes themselves, Ph-physically observable traits
co dominance is:
when both alleles are expressed equally in the phenotype
RH incompatibility occurs when
the child is RH+ and mom is RH-
what does apotosisi do?
eliminates damaged or unwanted cells
What mutations are associated with breast and ovarian cancers?
BRCA 1 and BRCA 2
the hayflick liit is:
the maximum number of cell divisions in normal human cells
what process in meiosis increases genetic diversity?
crossing over
what is the purpose of a pedigree?
to determine modes of inheritance and probabilities of genetic traits
where in the cell does protein sysnthesisi occur?
ribosome
what is the role of tRNA is protein synthesisis?
to bring amino acids to the ribosomes and bind to the mRNA codons
Which codon serves as the start codon in mRNA translation?
AUG
What is the term for a condition in which an individual has too many or too few chromosomes?
aneuploidy
what is the rp;e pf DNA repair enzymes in in preventing cancer?
to repair mutuations in DNA
What is unique about HeLa cells?
they are cancer cells that re ‘immortal’ and continue dividing forever
what happens AFTER DNA re[location but before crossing over in meiosis?
each chromosome is composed of two identical sister chromatids
the three things in mRNA that tRNAs recognize during translation are called:
codons
the process in mitosis and emiosis where chromosomes become visible is called:
chromosome condensation
crossing over occurs during:
meioisis between sister chromoatids of homologous chromosomes
Which if the following allele combinations for the ABO blood group would demonstrate codomininace? AO, BO, OO, AB
AB
during proteinsynthesis a _____brings an amino acid to the ribosome
tRNA
a zygote is formed as a result of
sperm fertilizing the ovum
What is nondisjuntion and what human condition is likely a result of it?
when a pair of homologous chromosomes fail to separate at anaphase so both go to same daughter cells. example is downs from trisomy 21
how many codons are used for the amino acid Leucine in protein synthesis?
6
if a cell in in the G0 stage, this means:
it;s not undergoing cell divisions
what are the names of the end types of cells from 1-mitosis and 2-meisosis?
diploid and haploid
what is Huntington’s disease
genetic disorder affecting brain and nervous system
apoptosis is ____?
programmed cell death
RH incompatibility could result in?
rh-mom, rh+ dad
sister chromatids have:
same genes and same alleles
consanguineous mating is:
blood relative mating
