unit 7 Flashcards
why do cells want to be small
big surface area to volume ratio so they can move faster
cell division
when cell divides in 2 daughter cells
cell cycle
cycle of cell growth and cell division
interphase
period of growth
mitosis
period of cell division
parts&order of interphase
-g1 phase: cell grows/proteins made
-s phase:cell copies chromosomes/dna made
-g2 phase:cell preps to divide
what do proteins found inside and outside the cell do
direct cells to speed up/slow down cell cycle
growth factors
special proteins that speed up/slow down cell growth/ division
cancer
uncontrolled cell division, mitosis out of control, caused by defects in the proteins
carcinogen
any environmental agent that causes canccer
genetic factors
can inherit genes from parents that increase chances of cancer
cancer forms
tumors that block nutrients from reaching healthy cells
metastasis
process where cancer enters the blood and spreads across the body
benign
not cancerous and doesnt spread
malignant
cancerous, harmful tumor
checkpoints checks
-does the cell need to divide
-is cell large enough
-have enough resources
-damaged?
-dna replicated right
g0 phase
phase of cell cycle where cell carries out normal tasks, not prepping to divide
apoptosis
programed cell death, happens when a cell doesn’t pass a checkpoint
how many circular chromosomes do prokaryotes have
1
prokaryote division
binary fission
binary fission
cell duplicates dna and new identical cells are formed
where does binary fission occur
bacteria
what are the structures dna is wrapped up in called
chromatin
chromatin
long strands of dna wrapped around proteins called histones, found in nucleus, chromatin wraps up into chromosomes
chromosomes
packages of dna, in nucleus, carry genetic info
somatic cells
body cells, have 46 chromosomes/23 pairs
gametes
sex cells (sperm/egg), 23 chromosomes, no pairs
sister chromatids
2 halves of a chromosome, each half is an exact copy of the other
centromere
structure that holds 2 sister chromatids together
mitosis
cell division, PMAT
prophase
chromatin coils into chromosomes, nuclear membrane starts to disappear, centrioles go to opposite side of the cell, spindle fibers start to form
centriole
small circular things attached to spindle fibers
spindle fibers
thread like things attached to chromosomes
metaphase
spindle fibers attach to centromeres, chromosomes line up I the middle of the cell
anaphase
sister chromatids go to the opposite sides of the cell
telophase
nuclear membrane reforms, chromosomes unwind, 2 new identical cells start to form
cytokinesis
not technically part of mitosis, but must occur afterward to fully separate cells ( divides, occurs after telophase)
cytokinesis in animal cells
animal cells only have one flexible cell membrane which is pulled in toward the center of the cell till it splits. That crease is called a cleavage furrow
cytokinesis in plant cells
plant cells have a cell membrane and a cell wall/ call wall can’t be pulled in, so a new one is created. plant cells builds a new cell plate between 2 nuclei
