BSCI 150 Exam 3 – Questions With Solutions (ch7) Cell cycle phases ✔️Ans - Interphase
- G1,
- G2,
- DNA synthesis (S)
- Replacement / Repair
Mitosis (M) phase Reasons for Mitotic/Mitosis Phase ✔️Ans - - Growth & Development
- Reproduction (Asexual: genetic duplicates/clones)
Interphase ✔️Ans - 90% of cell's "lifetime" Normal function
- makes proteins
- cell growth
- metabolism
If cell gets signal for division, cell duplicates structures, Esp. DNA Interphase - S phase ✔️Ans - DNA synthesis and chromosome replication Chromatin ✔️Ans - Chromosomes are compacted by being wrapped around histones and other proteins to form chromatin.(this copies in S phase) Histone ✔️Ans - DNA coils around, ("beads on a string") a protein organizes chromosomes Chromosome ✔️Ans - 1 long DNA molecule & histones elaborately packed carries genetic information in the form of genes Sister chromatids ✔️Ans - copy of each chromosome after chromosome duplication Centromere ✔️Ans - Area where the chromatids of a chromosome are attached 1 / 2
Mitotic spindle ✔️Ans - An assemblage of microtubules and associated proteins that involve in the movements of chromosomes during mitosis Mitosis ✔️Ans - Division of nucleus into 2 genetically identical daughter nuclei
Mitosis: Prophase ✔️Ans - stage 1 -- think "Prepare"
Chromatin in nucleus condenses to form chromosomes Begin formation of mitotic spindle
- pairs of centrioles move to opp. sides of nucleus
- Spindle fibers form bridge between the ends of the cell
Mitosis: Prometaphase ✔️Ans - Mitotic spindle fully formed
Nuclear envelope breaks down Chromosomes attach Mitosis: Metaphase ✔️Ans - stage 2 -- think "Meet / Middle" Chromosomes line up in middle (Some spindles not attached to chromosomes)
Mitosis: Anaphase ✔️Ans - stage 3 -- think "Away / Apart"
Sister chromatids separate as attached spindles shorten Chromosomes move toward poles Spindles not attached lengthen, pushing poles apart
Mitosis: Telophase ✔️Ans - stage 4 -- think "Two"
Spindle dis-assembles Nuclear envelopes form Chromosomes uncoil to chromatin Cytokinesis ✔️Ans - Division of cytoplasm into 2 cells Cytokinesis in animal cells ✔️Ans - Cell membrane drawn inward until cytoplasm is pinched into nearly equal parts
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