Biology Final: Mitosis/Meiosis, Genetics, Molecular Genetics/Biotechnology, Evolution, Ecology
Distribution of chromosomes in one type of cell division:
Four X's- two with two in each- four with one in each
Phases of interphase:
G1 phase, S phase, G2 phase, M phase
Meiosis:
a type of cell division producing gametes for reproduction
When a human egg is fertilized:
a zygote is formed
Tumor:
abnormal mass of cells
GEnome:
all GEnetic material of an organism
Impact of S phase:
all chromosomes now have identical twins
How many combined chromosomes would there be for a skin cell, an egg cell, and a brain cell for an organism with a haploid number of 10?
There would be twenty for a skin and brain cell, and ten for an egg cell.
If P53 gene cannot fix cycle, it performs:
apoptosis
Pairs 1-22 of chromosomes:
autosomes (homologous)
In eukaryotic organisms, chromosomes are synthesized:
before the phases of Mitosis
Somatic cells:
body (diploid) cells produced by mitosis
Sperm/egg cell:
both have 23 chromosomes, and come together to make a fertilized zygote of 46 chromosomes
A person is able to pass on skin cancer to their children if:
it is coded for in the genes
Cancer is genetic if:
it is coded for in the genes
kinetochores are located:
located on the centromere of chromosomes
Oogenesis:
meiosis in females, which makes one egg and 3 polar bodies
Spermatogenesis:
meiosis in males, which makes 4 haploid sperm cells
In both mitosis and meiosis, the spindle fibers which pull chromatids to the poles are made of:
microtubules
M phase:
mitosis/cytokinesis; 10 percent of cycle
Benign tumors:
non-cancerous tumors which may be harmful
Mitosis:
nuclear cell division resulting in 2 identical daughter cells (genetic equivalent of the parent)
In mitosis, chromosomes move to:
opposite ends of the cell so that the cell can evenly split into two
One gene responsible for stopping or regulating the cell cycle if DNA is damaged is the:
p53 gene gene
apoptosis:
programmed cell death (happens if a cell cannot be repaired)
(5) Stages of mitosis:
prophase, prometaphase, metaphase, anaphase, telophase (PPMAT)
Gametes:
sex (haploid) cells produced by meiosis
Pair 23 of chromosomes:
sex chromosomes (not homologous)
Homologous chromosomes:
similar autosomes (not identical) because they have the same location and "locus, but different pairs
Zygote:
single cell that forms after fertilization
Examples of gametes (sex cells) include:
sperm (male gametes) and egg (female gametes) cells, which are not homologous.
If kinetochores did not exist:
spindle fibers would not attach to the chromosomes
Chromosomes:
structures that contain genetic material which is passed from generation to generation of cells
Cytokinesis:
the division of the cytoplasm in a cell which occurs in both mitosis and meiosis; separates daughter cells
Locus:
the location of the gene in every chromosome (carry the same genes in the same order)
Oogenesis is the technical name for:
the process of the formation of egg cells
Meiosis is necessary for fertilization because:
it allows the combination of the sperm and egg cell, both with 23 chromosomes, to merge and become the fertilized zygote of 46 chromosomes.
(2) Functions of cytokinesis in plant cells:
1. A cell plate forms along midline 2. vesicles (like vacuoles) of cellulose line up in center to create new cell wall by cellulose being deposited between vesicle membranes
(2) Functions of metaphase:
1. Chromosomes move toward the metaphase plate; chromatids are aligned at the cell equator 2. Centrioles are positioned at opposite sides of cell
(3) Functions of telophase:
1. Daughter nuclei form at poles 2. Nuclear envelopes form around chromosomes and nucleoli reappears 3. chromosomes relax again into chromatin
(3) Functions of anaphase:
1. Sister chromatids split/move toward poles of cell 2. Chromosomes form a "V" shape due to kinetochore fibers attaching to middle of chromosome, being pulled by spindle fibers 3. Spindle fibers shorten as chromosomes near poles
(4) Characteristics of cancer cells:
1. lack differentiation 2. have no job/function 3. abnormal nuclei 4. may undergo angiogenesis/metastasis
(3) Functions of prometaphase:
1. nuclear membrane disintegrates 2. mitotic spindle fibers attach to kinetochores 3. spindle fibers begin to move the pairs of sister chromatids within the cell
(5) Functions of prophase:
1. nucleoli disappear 2. chromatin condenses into visible chromosomes 3. sister chromatids join at centromere 4. centrioles migrate 5. mitotic spindle begins to form between centrioles
(3) Functions of cytokinesis in animal cells:
1. performed as cleavage 2. cleavage furrow is formed near metaphase plate 3. mitotic spindle breaks and cells completely separate
Product of mitosis:
2 identical diploid daughter cells which both have 46 chromosomes
Represents the process the cell cycle for mitosis:
2n 2n 2n
Haploid number of chromosomes in an organism that has 34 chromosomes in its sperm cells:
34
Meiosis results in:
4 genetically variable haploid daughter cells (sperm/egg/polar bodies)
If the haploid number of chromosomes in an organism is 8, how many combined chromosomes would a kidney, sperm, and heart cell have?
40 (kidney=16, sperm=8, heart-16)
The diploid number of chromosomes in humans is:
46
How many chromosomes are made from meiosis?
92 chromosomes are made from this process
Crossing over:
Chromosomes transferring and exchanging genetic material to promote diversity and increase genetic variability
(9) Stages of meiosis:
Interphase, Prophase 1, Metaphase 1, Anaphase 1, Telophase 1, Prophase II, Metaphase II, Anaphase II, and Telophase II.
What types of cells undergo meiosis?
Only reproductive cells
Every female cell:
XX (23)
Every male cell:
XY (23)
If genetic content in autosomes or sex chromosomes don't match:
a genetic disorder results
Tetrads' function:
by traveling, they submit genetic information, get closer/switch
embryonic stem cell:
can be manipulated to become a different cell; controversially accepted as an organism
Malignant tumors:
cancerous tumors
Nondisjunction causes:
causes genetic disorders
G1 phase (1st growth phase):
cell increases in size and volume
nondisjunction (flaw of meiosis):
cells not separating, receiving too few or many chromosomes
The name for unorganized/relaxed DNA and protein:
chromatin
Chromatid:
copy of a newly copied chromosome (a single chromosome) which is still joined to the original copy by a centromere
S phase:
copying of DNA
G2 phase (2nd growth phase):
creates more room for the extra chromosomes by increasing cytoplasm volume
In meiosis, chromosomes move by:
crossing over occurring in Prophase 1
Function of pair 23:
determines gender
Sister chromatids line up in:
dyads in mitosis and tetrads in meiosis
Sister chromatid:
either of the two chromatids formed by replication of a single chromosome
Example of a locus:
gene that codes for the cleft chin gene
mitosis is important for:
growth/repair
adult stem cell:
has power to become cell of origination by tissue's function
Centromere:
holds 2 sister chromatids together (center of X)
A difference between mitosis and meiosis is:
in meiosis, duplicated chromosomes pair off in tetrads
Kinetochores:
the structure which forms on a chromatid during division, allowing it to attach to the spindle fiber on a chromosome.
After the zygote undergoes meiosis, it:
then undergoes mitosis to grow and develop.
Somatic cells exist in how many pairs:
this type of cell exists in 23 pairs and has a full set of 46 chromosomes
Gametes exist in which group:
this type of cell exists in group 23 and has a half set of 23 chromosomes
Cancer:
uncontrolled cell division that results in tumors and disease; an irregular form of mitosis
stem cell:
unspecialized cell without a particular function