Cell cycle (M1B1) Flashcards
The regular sequence of events that produce new cells is termed the…………
cell cycle
what’s the phase that’s the longest and most variable part of the interphase cycle?
G1
what are the 3 stages of the cell cycle and what happens during them?
– Interphase – cell grows into its mature size, makes a
copy of its DNA, and prepares for division.
– Mitosis – one copy of the DNA is distributed into each of its daughter cells
– Cytokinesis – the cytoplasm divides and organelles are distributed into the two new cell
Mitosis is conventionally divided into five phases which are?
PPMAT
– Prophase – Prometaphase – Metaphase – Anaphase – Telophase
Differences between mitosis and meiosis
mitosis: diploid to diploid ex. 46 to 46, 1 cell to 2 cells, growth and repair, somatic cells only, PMAT+ Cytokinesis 1
meiosis: diploid to haploid, 46 to 23, 1 cell to 4, reproductive cells only, PMAT + Cytokinesis 2
Interphase is made up of 3 separate parts which are?
– G1
–S
– G2
what is G0 phase?
cells exist in a quiescent (inactive) state, the cell is neither dividing nor preparing to divide
Cycling is activated in postmitotic G0 cells by protein signals from the extracellular environment called?
mitogens (growth factor)
bind to cell surface receptors and trigger a cascade of kinase signaling in the cells
what phase does the cell in for the most of its life?
interphase
what’s a homologous chromosome?
23 pairs of chromosomes one from the mother and one from the father (somatic cells only, no gamete)
what makes up the chromatid and is composed of DNA and proteins?
chromatin
what happens in G1?
cells doubles in size
Think of this phase as the cell just living its normal life.
what happens in S phase?
DNA synthesis
Think of this phase as placing the DNA on a copy machine.
what happens in G2?
cell prepares to divide and produces structures needed for cell division
(Think of this phase as the cell double checking everything it needs to divide.)
what are pieces of DNA that contain the instructions for building a protein?
genes
what happens in PMAT?
P: • Nucleusdisappears
• Spindle fibers form in the cytoplasm and attach to sister chromatids
M: they line up
A: sister chromatids are pulled to the opposite ends
T: after they arrive new nucleus forms
what is cytokinesis?
is the division of the cytoplasm
an egg and a sperm fuse to produce a………
zygote
what is the name for the fusion of gametes?
fertilization
the process where the homologous chromosomes pair all along their length is called?
synapsis
what is the exchange of genetic material from homologous chromosomes called?
crossing over
At the end of meiosis, each cell contains one half the genetic material (haploid or “n”) which is called?
reduction division
At the end of Meiosis II, there are……. haploid cells.
4
cycling is regulated by a family
of cytoplasmic proteins called?
cyclins
(With different cyclins
present during different cell cycle phases, each activates one or more specific cyclin-dependent kinases (CDKs)
