Mitosis and Meiosis and Binary Fission

Question 1

Mitosis and Cytokinesis:

DNA condenses to form______ .
Chromosomes line up along the_____ of the cells.
Cell _______ pull the two arms of each chromosome to opposite sides (poles) of the cell.
Cytokinesis - the entire cell_______ to form two identical________ cells.

Answer 1

Chromosomes
Centre
Fibres
Divides
Daughter

Question 2

Multicellular organisms, like ourselves, require a continuous supply of new cells.

What are the three reasons why new cells are required?

Answer 2

Growth (we need more cells as we grow)
Development (we need new cell types as we develop new tissues)
Repair (we need to replace the cells that we lose each day)

Question 3

What is the cell cycle?

Answer 3

The series of steps that take place as a cell grows and then divides

Question 4

Cellular growth - the cell gets ______ and produces more sub-cellular structures, such as mitochondria and _________.
DNA replication - _______ duplicate, so that each consists of ________ arms (copies).
More cell growth.
Mitosis - the _________ divides into two.
Cytokinesis - the _______ divides into two.

Answer 4

Larger
Ribosomes
Chromosomes
Two
DNA
Cell

Question 5

How many pairs of chromosomes do most human cells have?

Answer 5

23

Question 6

Are the cells created by mitosis genetically identical to each other, or genetically different?

Answer 6

Genetically identical

Question 7

When a cell divides by mitosis, how many cells are produced?

Answer 7

2

Question 8

What do we commonly call the cells produced by mitosis?

Answer 8

Daughter cells

Question 9

What is another name for gametes?

Answer 9

Sex cells

Question 10

Which two are examples of sex cells (gametes)?

Answer 10

Egg cells
Sperm cells

Question 11

What does the term ‘haploid’ mean?

Answer 11

A cell that only has half the normal amount of genetic material

Question 12

Are gametes haploid cells?

Answer 12

Yes

Question 13

How many chromosomes does a human gamete have?

Answer 13

23

Question 14

When two haploid cells join, they form a d______ cell.

Answer 14

diploid

Question 15

During the process of meiosis, how many times does the cell divide?

Answer 15

2

Question 16

As a result of meiosis, how many cells are produced?

Answer 16

4

Question 17

Are the cells produced by meiosis genetically identical to each other, or genetically unique?

Answer 17

Genetically unique

Question 18

Which type of organism(s) divide via binary fission?

Answer 18

Bacteria

Question 19

Is binary fission a type of mitosis, a type of meiosis, or different from either?

Answer 19

Different from either

Question 20

Are bacteria eukaryotic or prokaryotic?

Answer 20

Prokaryotic

Question 21

True or false? Bacteria are unicellular. This means that when they divide by binary fission they’re also reproducing as each new cell is a separate organism.

Answer 21

True

Question 22

When bacteria divide by binary fission, is it an example of asexual reproduction or sexual reproduction?

Answer 22

Asexual reproduction

Question 23

Which two things must a bacterial cell do before it can divide?

Answer 23

Replicate its genetic material
Grow

Question 24

Once a bacterial cell has grown and replicated its genetic material, it is ready to divide by binary fission.

Describe the stages of this process.

Answer 24

The two circular strands of DNA move to opposite sides of the cell
A new cell wall from down the middle of the cell
The two halves pull apart to form two cells

Question 25

During binary fission, are the plasmids always split equally between the two new cells?

Answer 25

No The plasmids are randomly arranged, so there are often more plasmids in one cell that the other.

Question 26

Which three conditions do bacteria require for fast growth?

Answer 26

Warm Moist Plenty of nutrients