Chapter One: Cell Division

Question 1

Cell Theory

Answer 1

All cells are derived from pre-existing cells.

Question 2

Chromosome

Answer 2

Large, tightly coiled DNA molecules

Question 3

Histone

Answer 3

Proteins that pack the DNA in tight coils during cell division

Question 4

Kinetochore proteins

Answer 4

Bind to centromere and attach chromosomes to spindle fibres.

Question 5

Centromere

Answer 5

Hold duplicated chromosomes together before separating in mitosis

Question 6

Telomere

Answer 6

The ends of chromosomes which are important in aging.

Question 7

Stages of the Cell Cycle (3)

Answer 7

1. G1: Cells mature and increase in size by making cytoplasm and organelles
2. S: Synthesis phase; DNA is replicated
3. G2: growth phase; cells makes structures needed to divide

Question 8

Binary Fission

Answer 8

Process of division from a parent cell to two identical daughter cells in prokaryotes.

Question 9

Mitosis: Prophase

Answer 9

• Chromatids attach by centromere
• Centrioles (animal cells) and microtubules (plant cells) move to opposite ends of the cells
• Kinetochore fibers attach to centromere
• Nucleolus and nuclear membrane disintegrate

Question 10

Mitosis: Metaphase

Answer 10

Chromosomes line up along equator the cell attached to the kinetochore fibres

Question 11

Mitosis: Anaphase

Answer 11

• kinetochore fibres attached to centromere pull sister chromatids apart
• chromosomes move to opposite poles of the cell

Question 12

Mitosis: Telophase

Answer 12

• nuclear membrane reforms around chromosomes
• Nucleolus reforms
• chromosomes less tightly coiled, appear as chromatin

Question 13

Cytokinesis

Answer 13

Cytoplasm and it’s organelles separate into two new daughter cells

Question 14

Cleavage Furrow

Answer 14

In animal cells; a groove that forms in between the two new cells in cytokinesis

Question 15

Cell Plate

Answer 15

In plant cells; a plate that forms in the middle of the cell where the new cell wall will be in cytokinesis.

Question 16

Meiosis l: Prophase

Answer 16

• chromosomes coil tightly, nuclear membrane and nucleolus disintegrate
• synapsis of homologous chromosomes occur, making tetrads
• Chromosomes in tetrad exchange fragments by crossing over

Question 17

Meiosis I: Metaphase

Answer 17

Tetrads become aligned in the center of the cell wall attached to spindle fibres

Question 18

Meiosis l: Anaphase

Answer 18

-homologous chromosomes seperate

Question 19

Meiosis l: Telophase

Answer 19

Females: 2nd cell in females is called the 1st polar body. 1st polar body dies due to uneven splitting of the cytoplasm

Question 20

Meiosis ll

Answer 20

• Mostly a mitotic division
• differences are independent assortment, DNA is not copied in between Meiosis l & ll, and in males 4 cells are produced called spermatids

Question 21

Meiosis l vs ll

Answer 21

• 1st division separates the homologous chromosomes in two intermediate cells
• 2nd division mitotic

Question 22

Cell Theory

Answer 22

All cells are derived from pre-existing cells.

Question 23

Chromosome

Answer 23

Large, tightly coiled DNA molecules

Question 24

Histone

Answer 24

Proteins that pack the DNA in tight coils during cell division

Question 25

Centromere

Answer 25

Hold duplicated chromosomes together before separating in mitosis

Question 26

Telomere

Answer 26

The ends of chromosomes which are important in aging.

Question 27

Stages of the Cell Cycle (3)

Answer 27

1. G1: Cells mature and increase in size by making cytoplasm and organelles 2. S: Synthesis phase; DNA is replicated 3. G2: growth phase; cells makes structures needed to divide

Question 28

Binary Fission

Answer 28

Process of division from a parent cell to two identical daughter cells in prokaryotes.

Question 29

Mitosis: Prophase

Answer 29

- Chromatids attach by centromere - Centrioles (animal cells) and microtubules (plant cells) move to opposite ends of the cells - Kinetochore fibers attach to centromere - Nucleolus and nuclear membrane disintegrate

Question 30

Mitosis: Metaphase

Answer 30

Chromosomes line up along equator the cell attached to the kinetochore fibres

Question 31

Mitosis: Anaphase

Answer 31

- kinetochore fibres attached to centromere pull sister chromatids apart - chromosomes move to opposite poles of the cell

Question 32

Mitosis: Telophase

Answer 32

- nuclear membrane reforms around chromosomes - Nucleolus reforms - chromosomes less tightly coiled, appear as chromatin

Question 33

Cytokinesis

Answer 33

Cytoplasm and it's organelles separate into two new daughter cells

Question 34

Cleavage Furrow

Answer 34

In animal cells; a groove that forms in between the two new cells in cytokinesis

Question 35

Cell Plate

Answer 35

In plant cells; a plate that forms in the middle of the cell where the new cell wall will be in cytokinesis.

Question 36

Meiosis l: Prophase

Answer 36

- chromosomes coil tightly, nuclear membrane and nucleolus disintegrate - synapsis of homologous chromosomes occur, making tetrads - Chromosomes in tetrad exchange fragments by crossing over

Question 37

Meiosis I: Metaphase

Answer 37

Tetrads become aligned in the center of the cell wall attached to spindle fibres

Question 38

Meiosis l: Anaphase

Answer 38

-homologous chromosomes seperate

Question 39

Meiosis l: Telophase

Answer 39

Females: 2nd cell in females is called the 1st polar body. 1st polar body dies due to uneven splitting of the cytoplasm

Question 40

Meiosis ll

Answer 40

- Mostly a mitotic division - differences are independent assortment, DNA is not copied in between Meiosis l & ll, and in males 4 cells are produced called spermatids

Question 41

Haploid

Answer 41

1N, cell with single set of chromosomes. Gametes are haploid cells until joining together.

Question 42

Diploid

Answer 42

2N, cells that have two sets of chromosomes

Question 43

Apoptosis

Answer 43

Programmed cell death of cells that are either not needed, or will cause damage to the organism