Unit 7: Cell cycle Flashcards
Interphase (G1, S, G2)
first phase of the cell cycle, cell prepares to divide; G1-growth, S-DNA replication, G2-prep for division
cell division
the process of splitting a parent cell into two daughter cells
mitosis (PMAT)
the phase of the cell cycle where the nucleus divides in two, made of four sub phases: prophase, metaphase, anaphase, and telophase
prophase
chromatin condenses into chromosomes, nucleus breaks down, spindles form
metaphase
chromosomes aligned in middle with spindles attached
anaphase
spindles pull chromosomes apart towards opposite ends of cells
telophase
nucleus reforms, chromosomes start to un-condense into chromatin , cell starts to pinch in to divide cytoplasm
cytokinesis
the division of the cytoplasm (and cytoplasmic organelles), normally overlaps with telophase
cell plate
forms during cytokinesis in plant cells in the middle, new membrane and cell wall build off cell plate to form two new cells
cleavage furrow
the pinched in area that is created when animals cells undergo cytokinesis
centrioles & centrosomes
centrioles are an organelle that produce spindles to aid in cell division, have two structures, and two of them during cell division; centrosomes are the area surrounding centrioles
spindle fibers
a system of microtubules that attach to chromosomes and help pull them apart in mitosis, form a fanning shape
parent cell
the original cell, before division
daughter cell
the two new cells produced by cell division
Gap 0
a phase outside of the cell cycle where cells “rest” (don’t divide), may happen so cell can differentiate, doesn’t have enough resources, organism reached maturity
cell differentiation
the process by which cells become specialized to perform a certain function
apoptosis
programmed cell death, cell and chromatin shrink, membrane breaks up, surrounding cells clean up remains
stem cells
unspecialized cells from which differentiated cells develop, adult stem cells are multipotent (can become a limited number of cell types), embryonic stem cells are pluripotent (can become any body cell type in body)
cancer
a condition casued by the loss of control over cell growth and division
chromosome
composed of two chromatids/ condensed chromatin, carries genetic information from parent to offspring
histone proteins
the proteins around which DNA coils to form chromatin
chromatid
one half of a chromosome, joined by centromere
chromatin
DNA coiled around histone proteins
centromere
the protein that holds two chromatids together to make a chromosome
DNA
the basic form of genetic information, made of nucleotides joined into long strands, double helix
complementary base pairs
DNA base pairs only bond with one other base (so they come in approximately equal proportions); adenine (A) with thymine (T), and guanine (G) with cytosine (C)
pyrimidines
one ringed DNA bases, C and T
purines
double ringed DNA bases, A and G
nucleotide
Nucleic acid monomer, the building blocks of DNA, composed of a sugar, phosphate group, and nitrogenous base
antiparallel
DNA strands run parallel to each other but in opposite directions (5’ to 3’ vs 3’ to 5’)
3’ end vs 5’ end
numbers correspond to carbon atoms in sugar molecules, 5’ end attaches to phosphate of next nucleotide
deoxyribose
the 5 carbon sugar found in DNA nucleotides
double helix
the shape of DNA, a twisted ladder
Chargraff’s rule
base pair rule, percentage of A=T and percentage of G=C
DNA replication
the process of a cell duplicating its DNA in order to divide
semi-conservative
describes DNA replication, in each new DNA molecule there is one new and one original strand
origin of replication
the point where two DNA strands start separating in order to replicate
replication fork
the fork shaped produced at the origin of replication where two DNA strands split
DNA helicase
the enzyme that “unzips” (separates) DNA strands by breaking hydrogen bonds
DNA polymerase
the enzyme that attaches to RNA primers and adds new DNA nucleotides onto DNA in the 5’ to 3’ direction following the base pair rule
DNA ligase
the enzyme that joins together okazaki fragments (connects nucleotides)
DNA nuclease
the enzyme that removes RNA primers (DNA polymerase replaces them with DNA)
leading strand
builds continuoulsy, 5’ end farthest from helicase
lagging strand
builds in chunks, 5’ end closest to helicase
Okazaki fragments
the DNA fragments that are built on the lagging strand
parent DNA
the original DNA strand that goes into replication
daughter DNA
the new DNA strand produced in DNA replication with one original strand (from parent) and one new strand (built in replication)
Totipotent
can become any type of cell and develop an organism on their own, think toti=total, ex: zygote cells (earliest stage of development) can turn into extraembryonic tissues (ex: placenta) or any cell type in the organism
Pluripotent
can become any type of cell in the organism, cannot develop an organism on their own, think pluri=plural, ex: embryonic stem cells can turn into type of cell/tissue in the organism but not extraembryonic tissues
Multipotent
can be become certain types of specialized cells, think multi, ex: adult stem cells-depending on location can become certain types of cells (skin, blood, etc)
