AND HEREDITY EXAM WITH COMPLETE
ANSWERS {GRADED A+}
Why does the cell cycle happen? - ✔✔as cells increase in volume, the
surface area decreases and demand for material resources increases
which limits cell size
interphase - ✔✔has 3 phases
G1= growth
S= synthesis of DNA
G2= preparation for mitosis
mitosis - ✔✔divison of the nucleus
-has 5 phases
prophase - ✔✔chromosomes become visible, nuclear envelop dissolves,
spindle forms
metaphase - ✔✔chromosomes line up in the middle of the cell
, anaphase - ✔✔chromosomes separate and move to opposite ends of the
cell
telophase - ✔✔the chromatids or chromosomes move to opposite ends of
the cell and two nuclei are formed
cytokinesis - ✔✔division of cytoplasm and reformation of cell membrane
animal cell: pinches in (cleavage) using microfilaments
plant cell: form cell plate reforms cell wall
internal controls - ✔✔enzymes and promoting factors
external signals: growth factors provide stop and go signs at the
checkpoints
how cancer forms? - ✔✔disruptions in cell cycle control(too much
division,defective tumor supressor genes, overactive genes) which are the
result of DNA damage to proto-oncogenes (regulatory genes) which make
products like cylins and cyclin-dependent kinases
mitosis - ✔✔used for growth and repair in animals; plants use mitosis to
make gametes and for growth or repair
-begins with 1 cell, makes 2 identical cells or clones;maintains
chromosome number
meiosis - ✔✔-occurs after interphase