Cell division Study guide answer key
1. Cell cycle: When the cell receives a signal to divide, it enters G1;
otherwise, the cell stays in G0 ( a resting phase). Examples of cells
who are in G0 phase: Nerve cells.
 G1: cell growth phase.
 S: DNA is copied
 G2: repair enzymes check for correct DNA copy and correct mistakes
if present. During this phase, the cell prepares to enter Mitosis.
2. Mitosis occurs in body cells such as skin, muscle, and bones.
Mitosis produces identical cells to parents( skin cells produce skin
cells). In metaphase, chromosomes line up and centromere splits
into 2.
Meiosis occurs in gametes cells ( sperm or egg), producing 4 haploid
cells different than the parent cell due to crossing over, independent
assortment and random fertilization. During Metaphase, homologous
chromosomes pair up ( synapsis).
3. Meiosis I
Prophase I: random orientation, crossing over.
Metaphase I: Synapsis ( pairing up of homologous chromosomes)
Anaphase I: pairs of chromosomes separates.
Meiosis II:
Prophase II: spindle fibers appear.
Metaphase II: chromosomes line up at the middle
Anaphase II: chromatids separate and move to the opposite sides.
TelophaseII: nuclear membrane forms around the chromosomes in
each 4 new cells.
4. Identify the diagrams of below:
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#5. During fertilization, a multicellular organism receives one set of
chromosome from the mother and one set of chromosomes from the father.
This is why offspring resemble their siblings or parents. Refer to the
diagram.
#6. Meiosis results in four haploid cells different than the original cells,
whereas mitosis results in 2 diploic cells identical to the parents.
#7 refer to the essential questions answer key.
#8 refer to the essential questions answer key.
#9 refer to your notes.
#10. Refer to your notes
# 12. refer to the essential questions answer key.
# 13,14 Gamete cells are used for reproduction and therefore have large
consequences on resulting generations, if those generations even ever
come into being. Somatic cells are simply body cells so these mutated cells
aren't too affective. BUT if there are a lot of mutations built up over time...it
can result in diseases and even cancer