Eukaryotic cell cycle

Question 1

main phases

Answer 1

interphase- longest phases, the cell doubles its mass and duplicated its components mitosis- the nucleus divides cytokinesis- the cytoplasm divides

Question 2

Interphase

Answer 2

-first phases, begins after the end of cell division
-made up of three phases G1, S and G2. G0 can also be a part of it after G1

Question 3

G1

Answer 3

• first growth phase
  -after cell division the cell is small so it grows back to its original size
  -more organelles are produced

Question 4

G0

Answer 4

cells will no longer divide but continue to perform their normal functions.
e.g. neurons, nerve or hear muscle cells

Question 5

S

Answer 5

-synthesis phase
- cell duplicated its DNA (linear) to make two sister chromatids

Question 6

G2

Answer 6

-second growth phase
-cell continues to grow and undergo metabolic activity
- the cell prepares cell division
- all the DNA is proofread to ensure no mistakes during Synthesis.

Question 7

Checkpoints

Answer 7

G1- verifies that the cell has grown properly, has enough resources to continue and DNA has not been damaged

G2- ensures that DNA has replicated properly and the cell has enough resources more mitosis

Metaphase: In mitosis and checks formation of the spindle fibers. incorrect formation can lead to chromosome malfunctions.

Question 8

Mitosis sub phases

Answer 8

Prophase, metaphase, Anaphase, Telophase

Question 9

Prophase

Answer 9

• chromosome condenses and becomes visible
  -centrosomes move towards the opposite sides of the cells (the poles)
  -spindle fibers begin to form
  -nuclear membrane disappears

Question 10

Metaphase

Answer 10

-spindle fibers attach to chromones at centromeres
-chromones align at the equator between the poles

Question 11

Anaphase

Answer 11

-the spindle fibers contract until the centromeres split, separating the sister chromatids
-the separated chromatids, now separate chromosomes are pulled towards the opposite poles by the spindle fibers.

Question 12

Telophase

Answer 12

-nuclear membranes reform around the two sets of chromosomes
-the spindle fibres disappear
-the chromosomes decondense to become long thin chromatin fibres again.

Question 13

Cytokinesis

Answer 13

can sometimes overlap with telophase
division of the cytoplasm

Question 14

Cytokinesis in animal cells

Answer 14

-cytoplasm pinches in as a ring of contractile proteins squeezes the centre of the cell. called cleavage furrow
-two daughter cells are pinched apart

Question 15

cytokinesis in plant cells

Answer 15

• a new plasma membrane and cell wall forms between the two cells
  -this growth, called the cell plate begins int eh center of the cell, and grows until it fully separates the two daughter cells.