Unit 4, Quiz 2

Question 1

Cells need to reproduce or divide so that organisms can _______ and __________ damaged cells.

Answer 1

1. Grow
2. Repair

Question 2

Most of a cell’s life is spent during a period of growth and development. What is this stage called?

Answer 2

Interphase

Question 3

Directions: Is the following statement true or false?

Interphase is technically a stage of mitosis.

Answer 3

False. Interphase is like the preperation for mitosis. This is the period where chromosomes duplicate themselves. It’s not an active phase of cell division.

Question 4

Give two examples of cells that are permanently stuck in interphase.

Answer 4

1. Nerve cells
2. Muscle cells

Question 5

What is mitosis?

Answer 5

Mitosis is the process in which a eukaryotic cell splits into two new daughter cells, each having the same number of chromosomes as the parent cell

Question 6

How many chromosomes is a healthy human supposed to have?

Answer 6

46

Question 7

Name the six stages of mitosis in order.

Answer 7

1. Interphase (technically not a part of mitosis)
2. Prophase
3. Metaphase
4. Anaphase
5. Telophase
6. Cytokinesis

Question 8

What is asexual reproduction?

Answer 8

The process in which one parent creates two identical offspring

Question 9

Directions: After being provided the definition, name the term to the best of your ability.

When a new plant grows from a fragment or cutting off of the parent.

Answer 9

This is referring to simple mitosis, in the context of vegetative propagation.

Question 10

What organisms use simple mitosis (vegetative propagation)?

Answer 10

Both potatoes and strawberries can reproduce through vegetative propagation, which involves simple mitosis.

Question 11

What is binary fission?
What is an example of an organism that uses it?

Answer 11

1. Binary fission is a method of asexual reproduction where DNA is duplicated and the cell grows bigger and splits
2. Bacteria

Question 12

Directions: True or False? If false, correct the statement.

Binary fission only occurs in single-celled organisms (prokaryotic).

Answer 12

True

Question 13

What is budding?
What are examples of animals that use this?

Answer 13

1. Budding is when the parent grows a mini-version of itself that eventually breaks off to form a new organism.
2. Some organisms that use this are hydra and jelly fish.

Question 14

If an organism can make new cells, tissues, or organs after injury, what is this process called?

Answer 14

Regeneration

Question 15

Directions: True or False? If false, correct the statement.

Regeneration is a form of asexual reproduction that starfish, worms, lizards, and the human liver use.

Answer 15

True

Question 16

What is sexual reproduction?

Answer 16

The process in which sex cells from 2 parents create similar offspring

Question 17

Gametes are another name for what?

Answer 17

Sex cells

Question 18

Directions: Fill in the blanks to the best of your ability.

Sperm is made by males in the _________. They are very _________, have a head, __________, and __________________.

Answer 18

1. Testicles
2. Small
3. Neck
4. Flagellum

Question 19

Directions: Fill in the blanks to the best of your ability.

Eggs are made by ____________ in the ___________. They are relatively __________ compared to sperm, and they contain ________.

Answer 19

1. Females
2. Ovaries
3. Large
4. Food

Question 20

How many pairs of homologous chromosomes do human body cells have?

Answer 20

23 pairs of homologous chromosomes, or 46 altogether

Question 21

When sperm (XY) and an egg (XX) fuse together (fertilization), what new organism is created?

Answer 21

Zygote

Question 22

Directions: True or False? If false, correct the statement.

All sperm created are XY.

Answer 22

False. 50 percent of sperm are XY, and the other half is XX.

Question 23

If an XX sperm fuses with an egg, is a boy or girl going to be birthed?

Answer 23

Girl (female)

Question 24

Directions: Fill in the blanks to the best of your ability.

In meiosis, a sex cell splits (or divides) _____ times, creating _______ new daughter cells, each having _________ the number of chromosomes as the parent cell.

Answer 24

1. Two
2. Four
3. Half

Question 25

**Directions: Fill in the blanks to the best of your ability.** In females one ______ and three ______________ are made every time meiosis occurs.

Answer 25

1. Egg 2. Polar bodies

Question 26

Where are chromosomes found in an organism?

Answer 26

Chromosomes are found in the nuclei of every cell.

Question 27

**Directions: True or False? If false, correct the statement.** An organism's genes are found on the chromosomes.

Answer 27

True

Question 28

What is a **gene**?

Answer 28

A gene is a segment of DNA; it is a set of instructions for an inherited trait ## Footnote Think of it like this: DNA is like a big instruction book, and genes are individual chapters in that book.

Question 29

What are the genes responsible for?

Answer 29

The production of proteins, and thus, all of the organism's traits.

Question 30

DNA has the shape of a spiral staircase or a "twisted" ladder. This shape is scientifically called what?

Answer 30

A double helix

Question 31

Who discovered the shape of DNA?

Answer 31

Watson and Crick. They won a nobel prize for this. Earlier work was conducted by Rosalind Franklin with an X-Ray.

Question 32

DNA is made up of smaller subunits called _____________.

Answer 32

Nucleotides

Question 33

Name the **three** things that each nucleotide in DNA consists of.

Answer 33

1. Phosphate 2. Sugar 3. Nitrogen Base

Question 34

Name the **four** nitrogen bases in DNA.

Answer 34

1. Adenine 2. Guanine 3. Cytosine 4. Thymine

Question 35

**Directions: Fill in the blanks to the best of your ability.** The "handrails" of the double helix molecule are made from the __________ and ___________ groups. The "steps" or "rungs" of the double helix molecule are made from the ___________________.

Answer 35

1. Sugars 2. Phosphate 3. Nitrogen bases

Question 36

What is **Chargaff's Rule**?

Answer 36

Chargaff's Rule is that adenine always matches with thymine, and cytosine always matches with guanine.

Question 37

**Directions: True or False? If false, correct the statement.** RNA is the chemical that actually helps the ribosomes make proteins. It is made from a single strand of DNA that has "unzipped" from the double helix shape.

Answer 37

True

Question 38

Name **two** main differences between RNA and DNA.

Answer 38

1. RNA is single-stranded. 2. RNA does not contain the nitrogen base thymine. Instead, uracil takes its place.