Topic 4: The Cell Cycle, Mitosis, Meiosis Flashcards
sex chromosomes
- 23
- contain genes that determine sex
autosomal chromosomes
- 1 - 22
- contain genes for somatic characteristics
- each autosomal chromosome pair is not identical but equivalent = homologous chromosome
Interphase: G1 phase
- growth, metabolism
- at end of G1, centrosomes replicate
- note: in some cells that do not divide again once mature (example: remain in G1) - in these cells it is termed G0 phase
- example: nerve + some muscle cells
Interphase: G1 phase
- g______, m______
- what replicates at end of G1?
- note: in osome cells that do not divide again once mater - in these cells it is termed ______ phase.
- growth, metabolism
- at end of G1, centrosomes replicate
- note: in some cells that do not divide again once mature (example: remain in G1) - in these cells it is termed Go phase
- example: nerve + some muscle cells
Interphase: S phase
- chromosomes replicate, but are still present as chromatin (not individually visible)
- ALWAYS occurs before division (mitosis and meiosis)
- replicates are called sister chromatids
Interphase: S phase
- replicates are called sister chromatids
- ?
- ?
- kinetochore = ?
- attached to each other at an area of DNA called the centromere
- kinetochore proteins (produced during S phase) attach to each centromere to form the kinetochore ( = protein + DNA complex, 1/chromatid)
- kinetochore = site of attachment of spindle microtubules
Interphase: G2 phase
- growth, metabolism
- production of enzymes and other proteins needed for cell division
kinetochore
site of attachment of spindle microtubules
kinetochore is composed of?
- protein
- DNA complex
- 1/chromatid
kinetochore proteins are produced during what phase?
S phase
mitotic phase
involves:
- mitosis = division of nuclear material (chromosomes)
- 4 phases, but continuous cycle
- PMAT
- 4 phases, but continuous cycle
- cytokinesis = division of cytoplasm
division of nuclear material
mitosis
division of cytoplasm
cytokineses
mitotic phase
when mitotic phase ends:
- mitosis & cytokinesis complete
- daughter cell go into interphase (G1)
- cycle starts over
site of attachment of spindle microtubules
kinetochore
Somatic cell formation: mitosis
Prophase
- chromosomes condense from chromatin form - become individually visible
- nucleoli/nuclear envelope disappear
- centrosomes move to either pole
- microtubules form spindle apparatus (starting at centrosomes) + attach to kinetichore proteins (Called kinetochore microtubules)
- spindle moves chromosomes toward cell equator
Somatic cell formation: mitosis
Prophase
chromosomes ________ (thicken, coil) from _______ form - become __________ _____
chromosomes condense (thicken, coil) from chromatin form - become individually visible
Somatic cell formation:
prophase
nucleoli/nuclear envelope _______
nucleoli/nuclear envelope disappear
Somatic cell formation: mitosis
Prophase
centrosomes ________________
centrosomes move to either pole
Somatic cell formation: mitosis
Prophase
- kinetochore proteins (called ______________)
- spindle moves chromosomes to___________
- called kinetochore microtubules
- spindle moves chromosomes toward cell equator
Somatic cell formation
Metaphase
46 chromosomes line up on cell equator
Somatic cell formation
Anaphase
- as the spindle microtubules shorten, the kinetochores are pulled away from each other - causing separation of centromeres, which results in separation of the chromatids
- 46 chromatids migrate to each pole
- cytokinesis (division of cytoplasm begins)
cytokinesis begins at what phase of mitosis?
anaphase
