Cell Cycle and Mitosis

Question 1

The Cell Cycle

Answer 1

The process in which a cell divides and replicates its DNA to produce genetically identical daughter cells:

• Interphase
• Mitosis
• Cytokinesis

Question 2

Interphase

Answer 2

Growth phase 1 (G1):

• The cell grows bigger and replicates its organelles (including centrioles)
• High amount of protein synthesis takes place to make new organelles

Synthesis Phase (S):
-DNA replication takes place

Growth Phase 2 (G2):

• The cell continues to grow and replicate organelles
• Enzymes needed to aid cell division are produced

Question 3

Mitosis

Ice Penguins Move Around The Caps

Answer 3

Occurs in somatic cells

-Interphase

• Prophase (Early and Late)
• Metaphase
• Anaphase
• Telophase (Early and Late)

-Cytokinesis

Question 4

Prophase

Answer 4

Early Prophase:
-DNA coils and condenses to form chromosomes

Late Prophase:

• The nuclear envelope disintegrates
• The centrosomes move to opposite poles of the cell
• Spindle fibres attach to the centromeres of the chromosomes

Question 5

Metaphase

“Meet”

Answer 5

• The chromosomes align at the equator of the cell at the centre of the spindle fibre
• Sister chromatids are still attached by a centromere

Question 6

Anaphase

“Apart”

Answer 6

• Spindle fibres shorten
• Centromeres divide and sister chromatids are separated
• Chromatids pulled by spindle fibres to opposite poles

Question 7

Telophase

Answer 7

Early Telophase:

• Spindle fibres break down
• Chromosomes start to unwind
• Nuclear envelope is created

Late Telophase:
-Microtubules contract, pinching cell membrane and forming a cleavage furrow

Question 8

Cytokinesis

Answer 8

The parental cell divides into two genetically identical daughter cells

Question 9

Mitosis in Plants

Answer 9

All the same except:

Late Prophase - No centrioles so spindle fibres form on the cell wall and are straight and parallel to each other

Telophase/Cytokinesis - Segments of cell wall align at the equator and fuse together to form a cell plate which separates the cell