Biology Test #1

Question 1

Cell Membrane

Answer 1

Separates the inside of the cell from outside and controls the flow of materials into and out of cell.

Question 2

Cell Wall (plants)

Answer 2

Tough structure that lays outside of cell membrane and provides support.

Question 3

Nucleus

Answer 3

Controls all cell activities and contains chromosomes.

Question 4

Chromosomes

Answer 4

Long strands of DNA

Question 5

Vesicles

Answer 5

Sacs that transport/store materials and help them pass the cell membrane to enter or exit.

Question 6

Chloroplasts (plants)

Answer 6

Trap energy from the sun, make glucose (sugar), then send to mitochondria to be broken down and power the cell.

Question 7

Mitochondria

Answer 7

Powerhouse of the cell. Energy is released from glucose to fuel cell activities.

Question 8

Cytoplasm

Answer 8

Empty space in the cell and holds cytosol, orgenelles, and other life supporting materials.

Question 9

Endoplasmic Reticulum

Answer 9

Connected to the nucleus and are channels that transport materials made in the cell.

Question 10

Ribosome

Answer 10

Help produce proteins that make up a cell’s structure and are required for activities needed for cell survival.

Question 11

Vacuole

Answer 11

Contain water and other materials. Store or transport small molecules.

Question 12

Cytoskeleton

Answer 12

Filaments and tubes that provide structure for the cell.

Question 13

Golgi Body

Answer 13

Sorts and packages proteins to transport out of the cell.

Question 14

Animal cells

Answer 14

Animal cells are round for mobility. Have many small vacuoles to facilitate the movement of substances in and out of the cell and carry/store waste, water, nutrients.

Question 15

Plant cells

Answer 15

Plant cells are rectangles for structure. Have a cell wall that provides structure, shape, support and protection. Have chloroplasts because they can’t get their sugar from eating food, like animals, make sugar from sun (photosynthesis). Have 1 or 2 really large vacuoles that store water.

Question 16

3 reasons that cells divide?

Answer 16

To heal and repair, growth, and reproduction.

Question 17

6 main parts of a DNA molecule.

Answer 17

Sugars and phosphates (the twisted ladder). Inside DNA are 4 nitrogen bases: Adenine, Thymine, Cytosine, and Guanine.

Question 18

Which 2 pairs of nitrogen bases combines?

Answer 18

Adenine and Thymine.
Guanine and Cytosine.

Question 19

List the stages of mitosis in the order that they occur.

Answer 19

PMAT: Prophase, Metaphase, Anaphase and Telophase.

Question 20

Prophase

Answer 20

Chromosomes condense and become visible. Nuclear membrane and nucleolus disappear in order to get chromosomes out of the nucleus. Spindle fibres form. Each chromosome contains two strands called sister cromatins held by centromere.

Question 21

Metaphase

Answer 21

Chromosomes line up in the middle of the cell. Centrosomes reach opposite ends of cell.

Question 22

Anaphase

Answer 22

Spindle fibres pull apart the chromosomes, moving them to opposite ends of the cell. Pulls them to the centrosomes.

Question 23

Telophase

Answer 23

Spindle fibres disappear. Nuclear membrane and nucleolus reappear. Chromosomes get thinner.

Question 24

What is a mutation?

Answer 24

A mutation is when there’s a change in the DNA base sequence. Usually happens when DNA is duplicated.

Question 25

Three ways gene mutations can occur

Answer 25

Substitution - when one of the bases (letters) is substituted for another random base.
Insertion - An extra base is inserted into the sequence. Means all the codons to the right are also altered.
Deletion - A base is deleted from the sequence. The letter beside it will move to the left and every letter after that, altering all those codons.

Question 26

What mutagens can cause mutations?

Answer 26

Electromagnetic Waves
Toxic Chemicals
Extreme Temperatures.

Question 27

Difference between cytokinesis in plants and animals

Answer 27

Animal - One cell with two nucleus in it and their own set of organelles. Specialized proteins form around the cell and start to pinch in the middle. Pinches the cell membrane until the cell is divided into two.
Plant - A cell plate is formed in the middle and grows outward to join the old cell wall. Cell plate then develops into a new cell wall, dividing the 2 cells.

Question 28

What is cancer?

Answer 28

Cancer causes cells to divide uncontrollably due to the result of a mutation. These cells can cause a tumour (group of cancer cells) and do not function as normal cells do.

Question 29

How cancer cells affect normal cells?

Answer 29

Cancer cells are strong cells that get to the nutrients faster than normal cells, which allows them to replicate, and kills the normal cells.

Question 30

Interphase

Answer 30

First stage of the cell cycle where the cell performs its normal functions and replicates its DNA.

Question 31

How does DNA replicate itself?

Answer 31

Before duplication - Inside the nucleus is “alphabet soup” where individual letters A, C, T, G hang out.
Unzip - Chemical bonds weaken and the two strands of DNA loosen their grip on each other. The two strands unzip leaving two individual strands.
Zip up - When DNA is unzipped, the letters in “alphabet soup” attach to the newly exposed strands. A only attaches to T and C only attatches to G.