Class Notes (811,481)
United States (314,602)
Biology (126)
BIOL 190 (47)
Angela Cox (29)
Lecture 17

BIOL 190 Lecture 17: cell cycle 1

2 Pages
Unlock Document

BIOL 190
Angela Cox

Cell Cycle Control ● Cell cycle control involves both internal and external signals ○ Regulatory proteins coded for by cell’s DNA Growth factors and other signals from the outside ● These signals function in each stage of cycle ( G1, S, G2, and M) and together act as “checkpoints” during the cycle Signal transduction pathways ● A signal transduction pathway- series of molecular changes ○ Convert a signal on the target cell’s surface to a specific response within the cell ● Signal transduction pathways are crucial to many cellular functions Cell Checkpoints ● Pass G1 Checkpoint if: ○ Sufficient nutrients ○ Growth factors present ○ Cell size is appropriate ○ No DNA damage ○ Environment favorable ● Growth factors are usually protein hormones that stimulate cell division Quiescence ● G0 (G zero) ● A nondividing state ● Response to a lack of growth factors ● Mature (fully differentiated)/ adult body cells ● reversible - depending on cell type ○ Mature nerve- or heart muscle cells will most likely remain in G0 ○ Lymphocytes (white blood cells) can be stimulated to reenter the cell cycle ○ Skin cells are not likely to enter G0 at all Apoptosis ● Cell suicide ○ Programmed cell death ○ Response to DNA damage Cellular Senescence ● Irreversible loss of the ability to divide ● Response to DNA damage ● Alternative to apoptosis ● Related to changes associated with aging Pass M checkpoint if: All chromosomes at
More Less

Related notes for BIOL 190

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.