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115 Cards in this Set
- Front
- Back
proper name for sex cells |
gametes |
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these separate during Anaphase II |
sister chromatids |
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chromosome number in gamete |
haploid |
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provides genetic diversity |
random alignment |
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chromosome number in body cell |
diploid |
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meiosis is significant because it creates |
genetic variation |
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daughter cells produced by meiosis are always |
genetically different |
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number of cell divisions in meiosis |
2 |
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diploid number of a human body cell |
46 |
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stage in meiosis during which tetra form |
prophase I |
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period of time between meiosis I and meiosis II |
interkinesis |
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haploid number of a human body cell |
23 |
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number of gametes produced from one parent cell during meiosis |
4 |
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place where meiosis takes place in male animals |
testes |
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occurs in ovaries and produces eggs |
oogenesis |
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chromosomes of similar size & shape, carrying same genes |
homologous chromosomes |
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homologous chromosome pairs separate during this stage of meiosis |
anaphase I |
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exchange of portions of chromatid between homologous chromosomes |
crossing over |
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stage in meiosis where chromosomes individually line up on spindle equator |
metaphase II |
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stage in meiosis where homologous pairs line up on the equator |
metaphase I |
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random arrangement of chromosomes along the spindle equator |
independent assortment |
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homologous chromosomes come together and line up side by side |
synapsis |
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fertilized egg cell |
zygote |
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stage in meiosis where cytokinesis produces 4 haploid cells |
telophase II |
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stage in meiosis when crossing over occurs |
prophase I |
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# of possible combinations of chromosomes during Metaphase I |
8.4 million |
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restores the diploid # of chromosomes |
fertilization |
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stage in meiosis when chromatids separate |
anaphase II |
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structures in a cell which make spindle fibers |
centrioles |
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describe crossing over |
when homologous chromosomes late in prophase I exchange genetic material |
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how is meiosis metaphase I different from mitosis metaphase? |
in meiosis (mI) the homologous chromosomes line up single file, but in mitosis they line up in pairs |
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in prophase II, why isn't there crossing over or synapsis? |
genetic material isnt exchanged its duplicated |
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homologous chromosomes pair up and form tetrad |
Prophase I |
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spindle fibers move homologous chromosomes to opposite sides |
anaphase I |
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nuclear membrane reforms, cytoplasm divides, 4 daughter cells formed |
telophase II |
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chromosomes line up along equator, not in homologous pairs |
Metaphase II |
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crossing-over occurs |
Prophase I |
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chromatids separate |
anaphase II |
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homolgs line up alone on equator |
metaphase II |
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homologs line up in pairs along equator |
Metaphase I |
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cytoplasm divides, 2 daughter cells are formed |
telophase I |
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what is the immediate end product of meiosis? |
gamete/sex cell |
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what is the chromosome # of each each offspring at the end of meiosis |
1/2 the parents |
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at what stage of meiosis do single-stranded chromosomes arrive at the poles of each cell |
telophase II |
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how many daughter cells are formed by the end of meiosis I? |
2 |
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how many offspring cells does a complete meiotic cycle produce? |
4 |
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at what stage of meiosis do homologous chromosomes separate from each other? |
anaphase I |
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what structure holds two sister chromatids together? |
centromere |
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at what stage of meiosis do the daughter cells first have the haploid # of chromosomes? |
telophase I |
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during prophase I of meiosis, homologous chromosomes synapse. What is a synapsed pair called? |
tetrad |
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what organelles form the meiotic poles in animal cells |
centrioles |
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what organelles form the meiotic poles in plant cells? |
centrosomes |
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at what stage of meiosis do single-stranded chromosomes migrate to opposite poles? |
anaphase II |
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at what stage of meiosis do double-stranded chromosomes arrive at the poles of each cell? |
telophase I |
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what structures pull chromosomes toward the poles? |
spindle fibers (generated by centrioles) |
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what small cells are formed at the same time an egg cell is formed in animal meiosis? |
polar bodies |
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at what stage of meiosis do chromosomes line up single file around the equator? |
metaphase II |
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at the end of meiosis in egg cell formation, how many functional egg cells are formed? Name? |
1- ovum |
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at the end of meiosis in sperm or spore cell formation, how many functional gametes are formed? |
4 |
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what are somatic cells? |
body cells(diploid cells) |
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what are gametes? |
sex cells |
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what's the relationship of a homologous pair? |
the pair is similar but not identical
|
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what makes up each strand of a homologous pair? |
chromatids |
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what's the relationship of chromatids in a chromosome? |
they're identical because they're a product of DNA replication |
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what's chromatin? |
long strands of DNA in the nucleus |
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in mitosis, chromosomes become visible in which phase? |
prophase |
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in mitosis, chromosomes become less tightly coiled & no longer visible in which phase |
telophase |
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is interphase a part of mitosis? |
no, but the two together make up the cell cycle |
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how many times does meiosis divide and does it repeat after that? |
divides twice, does not repeat |
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at the beginning of cell division, how many chromatids does a chromosome have? |
2 |
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what is the checkpoint for DNA damage? |
G2 |
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timing in the cell cycle in believed to be controlled by? |
cyclins |
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how do cancer cells differ from noncancerous cells? |
cancer cells do not respond to signals that stop cell growth |
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what's the end product of spermatogenesis? |
spermatozoa (sperm) |
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what's the end product of oogenesis? |
1 ovum and 3 polar bodies |
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what is it when homologous chromosomes line up next to each other? |
synapsis |
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define apoptosis |
programmed cell death |
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a nonfunctioning cell curing oogenesis |
polar body |
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compared to the mother cell, what is the chromosome # of each daughter cell at the end of mitosis? |
the same |
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at what stage of MITOSIS do spindle fibers attach to centromeres? |
metaphase |
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during which stage of interphase does a cell assemble materials needed for nuclear division? |
G2 |
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at what stage of mitosis do new nuclear membranes form? |
telophase |
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during which stage does a cell increase in size and number of organelles and perform its function? |
GI |
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sex cells produced by a sexually unidentifiable organisms |
spore |
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protiens that aid in the coiling of chromatin into chromosomes |
histomes |
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nuclear division that maintains the diploid number in a somatic cell |
mitosis |
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product of the centrosome in animal cells; produces spindle |
centrioles |
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unwound, accessible DNA in a on-dividing cell |
chromatin |
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in females, the haploid cell that divides by meiosis to produce and egg |
secondary oosyte |
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change in the DNA sequence as a result of inheritance, replication error, or environmental exposures |
mutation |
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number of sperm cells per meiotic division |
4 |
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gene that encodes a protein that promotes the cell cycle and inhibits apoptosis; mutation of this gene is found in many tumors |
proto-ocogene |
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ovum production in females |
oogenesis |
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in males, the diploid cell that divides by meiosis to produce sperm |
primary spermatocyte |
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longest part of the cell cycle; cell does its normal job, grows, and replicates DNA |
interphase |
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fertilized egg |
zygote |
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consists of interphase, mitosis, and cytokiniesis |
cell cycle |
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forms during cytokinesis in plants; product of golgi apparatus |
cell plate |
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caspase that activates "executioners" so apoptosis can occur |
initiators |
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the development of cancer, a disruption of the normal cell cycle |
carcinogenesis |
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agent like nicotine or uv radiation that causes damage to DNA |
mutagen |
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body cell that divides by process of mitosis |
somatic cell |
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type of reporduction via mitosis |
a-sexual |
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process that may occur if the goals of a checkpoint are not met |
apoptosis |
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structure consisting of homologous chromosomes that forms during synapsis |
tetrad |
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organelle that organizes cytoskeleton in eukaryotes |
centrosome |
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gene that encodes a protein that stop the cell cycle and promotes apoptosis; mutation of this gene is found in many tumors |
tumor suppressor |
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because of this, homologous pairs may orient towards either pole during metaphase I of meiosis |
independent assortment |
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structure made of tightly coiled DNA and protein in a diving cell |
chromosome |
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forms during cytokinesis in animals; product of the cytoskelton |
cleavage furrow |
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process during prophase I that increases variation in gametes |
crossing over |
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distribution and division of the cytoplasm between daughter cells |
cytokinesis |
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sperm production in males |
spermatogenesis |
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indentical parts of a chromosome prior to division |
chromatids |
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hormones that stimulate the start of the cell cycle |
growth factors |