Biology - Unit 7: Cell Cycle & Regulation, Mitosis & Meiosis
For every ONE meiotic division, females make _____ egg(s) and ______ polar bodies.
1 egg & 3 polar bodies
How many times do cells divide in mitosis?
1x
What is the result of meiosis cytokinesis 1?
2 unique cells are formed with doubled chromosomes
How many copies of each type of chromosome do we have?
2, one from mom & one from dad
How many kinds of chromosomes are in each of our cells?
23
How many times do cells divide in meiosis?
2x
How many phases make up the cell life cycle?
3
How many stages make up interphase and what are they?
3: G1, S, & G2
For every ONE meiotic division, males make ______ sperm.
4
What is the result of meiosis 2 and its cytokinesis that makes it different from mitosis?
4 unique cells with 1/2 the number of original chromosomes are made
How many chromosomes can be found in each human cell?
46
How many stages are there in mitosis and what are they?
4: Prophase, Metaphase, Anaphase, & Telophase
How many phases are there in meiosis?
8
What happens during S of Interphase?
DNA replication
What are the three cell life cycle phases?
Interphase, Mitosis, & Cytokinesis
Are all chromosome pairs in gamete cells homologous?
No, the 23rd chromosome in males has less DNA
Mitosis' telophase is the opposite of mitosis' ________________.
Prophase
T/F: There is no homologous pair rule. Mother & Father chromosomes can be on both the top and bottom row of chromosomes during meiosis' metaphase 1.
True
When does mitosis occur in a cell's life cycle?
after G2 interphase
When do female parent cells form?
at birth
When does cytokinesis occur?
at the end of or during telophase
In what cells does mitosis occur in?
body cells
What happens when cell growth is uncontrolled?
cancer
What is meiosis?
cell division in gamete (reproductive) cells
What is "normal cell activity" that occurs during Interphase G1 & G2?
cell growth/ATP energy, protein synthesis, cellular respiration, photosynthesis, metabolism
What happens to chromatids during mitosis' telophase?
chromatids are at the farthest ends of the cell
What happens to chromosomes during meiosis' prophase 1?
chromosomes become visible
What genetic info do different daughter cells have?
combinations of either mom & dad's chromatids
How often do male meiotic divisions occur?
daily, new parent & daughter cells are made continuously
What do female polar bodies do?
die for the benefit of the one egg
What type of chromosomes are found in mitosis' metaphase?
doubled chromosomes by way of DNA replication
In what cells does meiosis occur in?
gamete cells
What are haploids?
gamete cells (sperm & egg) that contain 23 chromosomes each
Cell _____________ & ________________ are regulated by the cell.
growth & division
What are some examples of external regulators?
growth factors (protein molecules) that speed up and slow down the cell cycle
What do cancer cells do that make them so dangerous?
ignore regulation signals, divide uncontrollably, form tumors, & stimulate other cells to become hazardous
What does the term "regulated" mean?
it can be turned on and off
What happens to the nuclear envelope during mitosis' prophase?
it disappears
Through what process are different daughter cells made?
meiosis
What is most similar to mitosis: meiosis 1 or meiosis 2?
meiosis 2
Through what process are identical daughter cells made?
mitosis
What happens during G1 of Interphase?
normal cell activity
What happens during G2 of Interphase?
normal cell activity
When do female meiotic divisions occur?
once every month after puberty
What is the result of mitosis?
one parent cell will have divided into 2 new identical daughter cells
What makes plant cell's cytokinesis different from animal cells'?
plant cells have no centrioles & asters and have a cell plate form in its center to divide it rather than a pinched cell membrane
What are internal regulators?
proteins inside the cell called cyclins
What are external regulators?
receptors on a cell's membrane
What do external regulators do?
respond to molecules outside of teh cell
What is interphase's other common name?
resting phase
What is visible during interphase?
scattered. invisible DNA
Why does DNA replicate?
so new cells can form
What forms during mitosis' prophase?
spindles
What happens to chromosomes during mitosis' anaphase?
split chromatids travel to opposite ends of the cell
What are some examples of internal regulators' job?
stop mitosis until DNA replications are complete & anaphase until chromosomes are properly lined up
What determines how long a person's life will be?
telomeres
What happens when a cell's telomere gets too short?
the cell stops dividing & works until it dies
What happens to chromosomes during meiosis' telophase 1?
the chromosomes that made up the homologous pairs are at opposite ends of the cell
What is mitosis?
the dividing of a cell's nucleus that ends with complete cell division
What is cytokinesis?
the division of the whole cell and its cytoplasmic organelles
What happens to chromosomes during meiosis' metaphase 1?
the meet up in the the cell's center organized as homologous pairs
What happens to chromosomes during meiosis' anaphase 1?
the rows separate and begin to move to opposite ends of the cell
Why do cells divide to fill cuts made in a petri dish?
they "sense" neighbor cells and are programmed to repair injury
What happens to chromosomes during mitosis' prophase?
they became visible
What happens to spindles during mitosis' telophase?
they disappear
What do spindles do in mitosis' metaphase?
they lengthen and attach to split centromeres
What happens to chromosomes during mitosis' metaphase?
they meet up along the cell's equator
What do spindles do during mitosis' anaphase?
they shorten, pulling apart chromatids
Why do cells divide?
to replace cells and repair and grow the body
What are homologous pairs?
two chromosomes that are the same type, but one is from the carrier's mom and one is from the carrier's dad
What forms during mitosis' telophase?
two new nuclei
What are telomeres?
unnecessary, buffer genetic information that are found on the ends of DNA molecules and shorten every cell division
What is the result of "crossing over?"
variety and reassurance that a baby will be related to and have genes from both parents
What is "crossing over?"
when homologous pairs rub off on each other and exchange genetic info
What are diploids?
zygotes (two gamete cells) that contain 46 chromosomes each
