Lecture 10- Cell Cycle Flashcards
What are the three functions of cell division?
Reproduction, tissue renewal, & growth/development
What is chromatin?
Complex of loose DNA & proteins
What is a nucleosome?
DNA wound around histone proteins
What is ploidy?
The number of sets of chromosomes
What is a centromere?
The region of a chromosome that links a pair of sister chromatids
What is the first step of the cell cycle?
Interphase
What ploidy change occurs during mitosis?
Ploidy does not change during mitosis
What type of chromosomes do prokaryotes have?
Single circular chromosome
How do prokaryotes reproduce?
Binary fission
What is the longest phase of the cell cycle?
Cell spends ~90% of its life in G1
What occurs during the G1 phase of interphase?
Protein manufacturing
What occurs during the S phase of interphase?
Chromosomes duplicate into identical sister chromatids & kinetochores begin to form
What occurs during the G2 phase of interphase?
Rapid cell growth & centrioles duplicate
What occurs during prophase?
Chromosomes condense, mitotic spindle forms, nuclear envelope and nucleolus disappear, & centrosomes move to opposite poles
When does metaphase begin?
When the spindle fibers attach to the kinetochores
What occurs during metaphase?
Chromosomes align along metaphase plate (equatorial line)
When does metaphase end?
When the chromosomes are finished lining up at the equator
What is the longest phase of mitosis?
Metaphase
What occurs during anaphase?
Cohesion proteins cleaved by an enzyme -> chromosomes move to opposite poles (disjunction)
What is the shortest phase of mitosis?
Anaphase
What occurs during telophase?
Nuclear envelopes reform around the two new daughter cells
What occurs during cytokinesis?
Cytoplasm divides -> each daughter cell gets a full set of chromosomes and organelles
What structure is formed during cytokinesis in an animal cell?
Cleavage furrow
What structure is formed during cytokinesis in a plant cell?
Cell plate
How many many chromosomes do human somatic cells contain?
23 pairs of 2 -> 46 total chromosomes
How many chromosomes do human gametes contain?
Haploid (n) -> 23
What is the overall goal of mitosis?
Make identical daughter cells
What are centrosomes composed of?
2 centrioles
Where do kinetochores grow from?
Centromere