Mitosis and Meiosis (Unit 5 - Part 1) Flashcards
cell division
one cell divides/splits into 2 cells (division of the cell and its genetic material - DNA)
purpose of mitosis
mainly growth and repair (exception is unicellular organisms)
purpose of meiosis
reproduction
mitosis
a type of cell division that results in 2 genetically identical daughter cells
meiosis
a type of cell division that results in 4 genetically different daughter cells
end result of mitosis
-2 daughter cells that are genetically identical to the original (parent) cell
-DNA is replicated and divided into 2 cells
Where does mitosis occur?
in multicellular organisms
DNA
a molecule that gets coiled into a structure called a chromosomes
How many chromosomes do human cells have?
46
diploid number (2n)
contains 2 complete sets of chromosomes, one set from each parent
nucleus then _____
chromosomes then DNA
multicellular organisms do mitosis for____
growth, repair, or replacement
unicellular organisms do mitosis for ___
reproduction
phases of mitosis
IPMAT (interphase, prophase, metaphase, anaphase, telophase)
interphase
the cell copies its DNA and grows in preparation for division (spends the most time in this phase)
prophase
DNA and proteins condense into tightly coiled chromosomes and centrioles begin to move to opposite sides of the cell
metaphase
spindle fibers attach to each chromosome and they align along the middle of the cell
anaphase
sister chromatids separate to opposite sides of the cell
telophase
nuclear membranes start to form, chromosomes uncoil, and spindle fibers fall apart
cytokinesis
the cell is split, two diploid cells form, and each is genetically identical
cancer
uncontrolled cell division (aka mitosis out of control)
cancer cells divide ______ and ___ than normal, healthy cells
more often and faster
tumor
an abnormal mass (growth) of cells
benign
non cancerous cells
malignant
cancerous tumor
fission
a type of asexual reproduction where the parent cell doubles in size and splits and it makes 2 identical cells
budding
a type of asexual reproduction where the parent organism divides itself into 2 unequal parts (a bud forms) and they are identical
cloning
another name for asexual reproduction that can only be done in a lab and does not happen in nature
advantages of asexual reproduction
fast, no mate needed, and population can increase rapidly
disadvantages of asexual reproduction
no genetic variation (the entire population is more likely to be wiped out with a change in environment or exposure to a disease