Science - Biology Quiz #2

Question 1

What does the cell look like at interphase (before S phase) ?

Answer 1

• DNA is long thin uncoiled material called chromatin
• One pair of centriles or one centrosome
• Nucleus is intect

Question 2

What does the cell look like at interphase (after S phase) ?

Answer 2

• DNA has duplicated and sister chromatids are joined at the centromere
• Centrioles and all other organelles are duplicated

Question 3

What does the cell look like at prophase?

Answer 3

• DNA condenses into vsible chromosomes
• Centioles migraes to the poles and start to release spindle fibers forming a mitotic spindle
• Nucleolus and nuclear membrane disapear

Question 4

What does the cell look like at metaphase?

Answer 4

• Chromosomes are lined up on the metaphase equator
• Mitotic spindle pulls chromosomes
• Spindle fibers attach to the centromere

Question 5

What does the cell look like at anaphase?

Answer 5

• Sister chromatids are separated at the centromere

- Spindle fibers shorted to pull the chromosomes but lengthen to stretch the cell membrane

Question 6

What does the cell look like at telophase?

Answer 6

• Nuclear membrane reformes
• Nucleolus reappears
• Mitotic spindle (centrocomes) dissolves (spindle fibers pulled in )

Animal - cleavage furrow formed
Plant - cell plate formed

Question 7

What does the cell look like at cytokinesis?

Answer 7

• Two separated cells

- Cytoplasm duplicated

Question 8

Identify parts during Metaphase (lined Up)

Answer 8

• Centriole (lil power box thing at the poles)
• Spindle fibers (the lines)
• Sister chromatids

Question 9

What is the cell cycle?

Answer 9

Interphase: G1, S, G2
Mitosis: Prophase, Metaphase, Anaphase, Telophase
Cytokinesis

Question 10

What happens during G1?

Answer 10

• The cell is carrying out routine functions
• Growing in size
• Making new proteins and organelles
• The nucleus is well-defined and surrounded by the nuclear envelope

Question 11

What happens during S?

Answer 11

• DNA is replicated in preparation for cell division

Question 12

What happens during G2?

Answer 12

• The cell prepares for division by forming microtubules and other organelles or molecules that the cell may need to divide.

Question 13

What is mitosis?

Answer 13

The process in which two nuclei are formed, each with an identical set of chromosomes.

Question 14

What happens during prophase?

Answer 14

• The cell prepares for nuclear division by breaking down the nuclear envelope
• The chromosomes condense and are now visible
• The mitotic spindle is formed
• Centrioles move to opposite sides of the cell

Question 15

What happens during metaphase?

Answer 15

• The centrioles are established on opposite ends of the cell
• The chromosomes line up in the cell’s equator (middle) and attach to the spindle fibers.

Question 16

What happens during anaphase?

Answer 16

• The spindle fibers shorten, pulling the chromatids to opposite poles of the cell
• Centromeres are separated, the chromosomes are no longer attached

Question 17

What happens during telophase?

Answer 17

• The nuclear envelope reforms
• Chromosomes disperse into chromatin
• Spindle fibers withdraw

Question 18

What happens during cytokinesis?

Answer 18

The cell splitting in half to form two new cells, each with its own nuclei and DNA.

Question 19

Mitosis in Plant vs Animal Cells

Answer 19

Animal Cells

1. Contain centrioles- which are made up of microtubules and help to form the spindle fibers.
2. Upon telophase, the spindle fibers tighten around the cell membrane until the animal cell cleaves into two new cells.

Plant cells

1. Do not contain centrioles, but form a preprophase band made up of microtubules. It forms right before prophase, helps form the mitotic spindle.
2. Upon telophase, a cell plate is formed between the two nuclei, which divides the cell wall and creates two new cells.

Question 20

Asexual & Sexual Reproduction

Answer 20

Asexual Production - reproduction of an organism in which one original organism makes an identical copy of itself.
Sexual reproduction - reproduction of an organism by combining genetic material from two different individuals of different sexes.

Question 21

Cancer - examples & causes

Answer 21

Cancer is a result of a haywire cell cycle. If the genes are mutated in some way, they will not work properly- and cell division may become out of control, leading to cancer.

Radiation UV rays from the sun can cause csncer through damage to DNA.

Question 22

What does a centriole do?

Answer 22

The centrioles form the areas that mitotic spindle forms and those mitotic spindles go and attach to each of the chromosomes and pull the chromosomes to opposite ends of the cell to allow cytokinesis to occur.