Topic 1

Question 1

What are the 3 components of the cell theory and what is the purpose of this theory?

Answer 1

• All living things are composed of cells
• Cells are the smallest unit of life
• Cells come from pre-existing cells

Question 2

Explain an example of an emergent property that arises in the body.

Answer 2

Cellular components interact so that the organism can carry out a range of more complicated functions.

Ex. Cells form tissues, tissues form organs, and organs form systems.

Question 3

Describe an example of cells undergoing specialization in the body, and for what purpose.

Answer 3

The expression of some genes from the organisms genome in the cell, but not others

This process produces cells for a specific purpose.

Question 4

What is the relationship between surface area and volume in cells?

Answer 4

Volume: Determines the level of metabolic reactions

SA: Determines the rate of exchange of materials with the outside environment

As volume increases so does SA but not in the same proportion

Question 5

Explain how stem cells would help a patient with Stargardt’s disease.

Answer 5

Stem cells are injected into the retina

The number of cells then increases

These cells replace the damage cells with new ones.

Question 6

Why might stem cells be considered pluripotent?

Answer 6

Because they can become any cell type.

Question 7

What are the limitations of adult stem cells?

Answer 7

• Difficult to obtain, very few are available
• Some tissues contain no adult cells
• Differentiate into fewer cell types.

Question 8

In what ways are eukaryotic cells more complex than prokaryotic cells?

Answer 8

Prokaryotic cells are more simple. Less internal components with no compartmentalization.

Question 9

What is the difference between prokaryotic DNA and eukaryotic DNA?

Answer 9

Prokaryotic DNA: A single circular chromosome

Eukaryotic: DNA is found in the nucleus (A closed membrane). Linear chromosomes.

Question 10

Explain the process of binary fission in prokaryotic cells.

Answer 10

When prokaryotic cells split themselves from one cell into 2.

Question 11

Explain 3 structures and their functions in a eukaryotic cell.

Answer 11

Mitochondria: is where the ATP of the cell is produced. Enclosed by a double membrane

Ribosomes: Small structures that build protein molecules, not enclosed by a membrane.

Plasma membrane: Controls movement of materials in and out of the cell.

Question 12

Suggest why the heads and tails of phospholipid molecules are oriented the way they

Answer 12

The head of the phospholipids is hydrophilic (attracted to water). While the tail is hydrophobic, (repelled by water.

Question 13

Why are phospholipids considered “amphipathic”?

Answer 13

Because it has polar, and non-polar areas.

Question 14

Simple diffusion

Answer 14

Move small nonpolar molecules from a high concentration to a low concentration.

Question 15

Facilitated diffusion

Answer 15

Larger polar molecules moving from a high concentration to a low concentration through the assistance of an integrated protein channel.

Question 16

Osmosis

Answer 16

The movement of water from a low solute concentration to a high solute concentration. Assisted by aquaporins (Integral protein)

Question 17

Hypertonic

Answer 17

High concentration of solute outside of the cell. Water will diffuse outside of the cell

Question 18

Hypotonic

Answer 18

Low concentration of solute outside of the cell. Water will diffuse into the cell

Question 19

Isotonic

Answer 19

Equal amount of solute inside and outside of the cell.

Question 20

Sodium - Potasium Pump

Answer 20

• Neurons need a gradient of high concentrations of sodium on the outside and high concentrations of potassium on the inside.
• 3 sodium ions bind to the internal sites of the pump
• ATP is used to alter the shape of the protein channel and move the sodium to the outside of the cell.
• This alteration opens 2 sites for potassium to bind
• The phosphate group is released from the protein causing it to go back to its original form, releasing sodium into the cell.

Question 21

What is the potassium-sodium ratio?

Answer 21

3 sodium to 2 potassium moved via the pump.

Question 22

Bulk transport

Answer 22

The movement of large amounts of particles into and out of the cell. (Uses ATP)

Question 23

Endocytosis

Answer 23

Taking a large sum of particles into the cell
- The membrane folds into itself trapping the solution
- Substance is enclosed by phospholipids (vessicle)

Question 24

Exocytosis

Answer 24

The release of large amounts of particles to the outside of the cell.
- Vesicle fuse with the membrane
- Push the internal content to the outside

Question 25

Mitosis

Answer 25

The mother cell splits creating 2 genetically identical daughter cells.

Question 26

Interphase

Answer 26

4 stages
- Gap 1 = normal functions, growing
- Synthesis = DNA gets replicated
- Gap 2 = Normal functions, prepares for cell division
- Gap 0 = No division is happening

Question 27

Prophase

Answer 27

• Nuclear membrane breaks down
• DNA condenses into chromosomes
• Spindle fibers begin to form

Question 28

Metaphase

Answer 28

Chromosomes are lined to the center of the cell through spindle fibers.
- Spindle fiber attaches to the centomers.

Question 29

Anaphase

Answer 29

Spindle fiber pulls the sister chromatids.

Question 30

Telophase

Answer 30

Spindle fibers break down and a new nucleus begins to form.

Question 31

Cytokinesis

Answer 31

The splitting of the cell

Question 32

Cyclins

Answer 32

A protein that controls the division of the cell.

Question 33

Cancerous cell

Answer 33

The uncontrolled cell division

Question 34

Mutagen and examples

Answer 34

A cancer-causing agent that alters the DNA of an organism.
- Xrays
- Arsenic
- Viruses

Question 35

Oncogene

Answer 35

If a mutation occurs on an oncogene it can cause cancer.

Question 36

Mutation

Answer 36

Is a change in an organism’s genetic code (DNA).

Question 37

Metastasis

Answer 37

The spread of cancer from its original location to other places in the body.