MS51-57 Test Flashcards
4 main phases of cell cycle?
Mitotic (M phase)
G1
Synthesis (S phase
G2
what happens in M phase?
process of nuclear division
in which chromosomes are paired then divided creating two daughter cells through a 5 step process
5 steps of M phase?
prophase metaphase anaphase telophase cytokinesis
what happens in G1?
growth and activity
what happens in S phase?
DNA is replicated
what happens in G2?
continued growth and building of spindle fibers and centrioles
what are growth factors?
a protein boosting growth of a tissue
what are cyclins?
a protein that initiates Mitosis (M)
cells that don’t divide?
neurons
muscle cells
red blood cells
cells that often divide?
skin cells
intestinal tract lining cells
nail/hair cells
what are stem cells?
cells that can permanetly change into another type of cell
what are gametes?
sex cells, either eggs or sperm
contain half the # of normal chromosomes
when joined produce a full set
what is asexual reproduction?
does not require two organisms to produce offspring; offspring are identical to parents
what is sexual reproduction?
requires two multicellular organisms and the offspring have a 50/50 mix of alleles from both parents
kinds of asexual and who use it?
budding (lots of division at one site) yeast and coral
fragmentation (a piece of you becomes new) plants and sponges
kind of sexual and who use it?
bacterial conjugation; bacteria
meiosis 1/2;for gametes
mitosis; for growth/repair/ maintenance
what is interphase?
G1, S, G2
what is cytokinesis?
cytoplasmic division producing 2 daughter cells
what is Go?
a resting non-dividing cell that exited the cell cycle
how is the cell cycle controlled?
growth factors-> cyclins -> CDK’s
what stops the cell cycle?
abnormalities such as;
DNA damage
mistakes in DNA replication
mitotic spindle malfunctions
what happens if cell cycle continues through abnormalities?
can lead to cancer or other diseases
what is a mutation?
change in DNA sequence that can be passed on
can be silent
what can cause a mutation?
alteration of base DNA
destruction/introduction/moving of genes/chromosomes
what are tumor suppressor genes?
(AKA antioncogene) a cell that protects the cell from a step that leads to cancer
what is proto-oncogene?
a normal gene that when altered becomes oncogene which contributes to cancer
some signal cell division or regulate apoptosis
what is P53?
a gene regulating apoptosis, suppresses tumors, regulates cell cycle, and stops cell division if there is damaged DNA
benign tumors?
non-cancerous
non-spreading
malignant tumors?
cancerous out of control cells
can invade other tissue which spreads and leads to metastasis
cancer facts?
40% of people diagnosed
200 types
30% due to tobacco
1 in 4 deaths by cancer
what is cancer?
characterized by tumors, which when one gains the ability to spread becomes cancer
what causes cancer?
mutations in genes controlling the cell cycle
10% of cancer is hereditary
what is stage 4 cancer?
spread of tumors from original site
how to grow from benign to malignant?
angiogenesis
loss of cell adhesion
loss of anchorage dependance
what are haploids?
1 set of chromosomes
use meiosis
called gametes
what are diploids?
2 sets of chromosomes
use mitosis
somatic cells
what is chromatin?
the material that composes chromosomes (except bacteria)
made of protein, DNA, and RNA
what is Histone Proteins?
package and order DNA
mainly in chromatin
what are chromosomes made of?
chromatin
vertebrates are usually?
diploid (1 mat. 1 pat.)
what are somatic cells?
(2n)body cells that build an individual
haploid cells?
gametes (n)
how many homologous pairs are in humans?
23
how many chromosomes are in humans? how many are autosomal (non-sex)
46
44
in gametes how many chromosomes? how many are autosomal?
23
22
what is Karyotype?
shows the # and physical appearance of chromosomes in a cell’s nucleus
cytokinesis in animal and plant cells?
animal= cleavage furrow plant= cell plate
what are germ line cells?
sex cells
what is reduction division?
AKA meiosis; division of a germ cell into 4 gametes
what is a tetrad?
AKA bivalent; a pair of paternal and maternal chromosomes
what is crossing over?
process of exchanging portions of maternal and paternal chromosomes
what is radiation?
targeted radiation waves to prevent cell division in cancer
what is chemotherapy?
a cocktail of drugs targeting both cancer and healthy cells, killing them
meiosis?
nuclear division of germ line cells creating 4 daughter cells through reduction division (2n->n)
reduction division does what?
reduces 2n germ line cells to 1n gametes through separation of homologous pairs
end of meiosis 1?
2 haploid daughter cells
what is metastasis?
spread of cancer cells from a tumor
what is apoptosis?
programmed cell death
