Lab 4

Question 1

What is the key process by which oxygen and nutrients move into cells and waste products leave?

Answer 1

Diffusion

Question 2

Diffusion is the movement of molecules from what to what?

Answer 2

High concentration to low concentration

Question 3

There is a cube that measures 3cm x 3cm x 3cm.

What is the surface area of one side?

Answer 3

9cm²

Question 4

There is a cube that measures 2cm x 2cm x 2cm.

What is the volume?

Answer 4

8cm³

Question 5

There is a cube that measures 5cm x 5cm x 5cm.

What is the surface area?

Answer 5

150cm²

Question 6

What is the formula to find the surface area of a cube?

Answer 6

L x W x # of sides

Question 7

Should the surface area be squared or cubed?

Answer 7

squared

Question 8

Should volume be squared or cubed?

Answer 8

Cubed

Question 9

Regarding absorption:

What is the danger of a cell that is too small?

Answer 9

The molecules will pass in and out of the cell too quickly to absorb needed nutrients.

Question 10

Regarding absorption:

What are the concerns with a cell that is too large?

Answer 10

Nutrients may take too long to reach the center of the cell.

Question 11

Regarding absorption:

What are we looking for in a cell for best absorption?

Answer 11

A cell that is just the right size where nutrients and waste can enter and exit the cell in balance.

Question 12

Regarding absorption:

What is the problem with a cell that has a high volume to surface area ratio?

Answer 12

It may not be able to absorb needed molecules fast enough.

Question 13

Regarding absorption:

If a cell has a high volume to surface area, how could it increase its surface area to negate the negative effects?

Answer 13

Form microvilli to increase the surface area on the apical side.

Question 14

In the agar cube experiment, what were some of the sources of possible error?

Answer 14

• The size of the blocks may not perfectly measured and cut
• Timing: When they are submerged and taken out must be at the same time for accurate comparison.

Question 15

Name the main orgenelles of the cell with a brief explaination of its function.

Answer 15

1. Nucleus: Duplicate DNA (Transcription)
2. Endoplasmic Reticulum (Smooth): Detoxifies alcohol
3. Endoplasmic Reticulum (Rough): Creates proteins (houses the ribosomes that do it)
4. Ribosomes: Create proteins (Translation)
5. Golgi Complex: Tags, Bags and ships out proteins for intracellular or extracellular use
6. Mitochondria: Produce energy (ATP)

Question 16

What three ways can a cell be altered to increase its diffusion ability?

Answer 16

1. Increase surface area
2. Stretch it
3. Form Microvilli

Question 17

What organelle prevents a squamous cell from being completely flat?

Answer 17

Nucleus

Question 18

For a cell to be specialized for energy production, what organelle would it need an abundance of?

Answer 18

Mitochondria

Question 19

For a cell to be specialized in protein production, what organelle would it need to have an abundance of?

Answer 19

Rough ER/Ribosomes

Question 20

For a cell to be specialized for detoxification, what organelle would it need an abundance of?

Answer 20

Smooth ER

Question 21

What functions are columnal and cuboidal cells good for?

Answer 21

Absorption and secretion

Question 22

To increase its absorption capability, a columnar cell would form what?

Answer 22

Microvilli (brush border)

Question 23

MIcrovilli are on what side of the cell?

A) apical side

B) basal side

Answer 23

Apical

Question 24

What is the process of cell division called?

Answer 24

Mitosis

Question 25

What are the stages of Mitosis?

Answer 25

* Prophase * Metaphase * Anaphase * Telaphase

Question 26

What occurs in Prophase? Why is it important?

Answer 26

* Chromatin condenses into chromosomes * Nuclear envelope breaks down (disintegrates) * Centrioles migrate to opposite sides and grow spindles Importance? * The duplicated chromosomes must be free to separate to opposite sides of the cell. * Centrioles will pull all duplicated material to their opposite poles (during anaphase)

Question 27

What occurs in Metaphase? Why is it important?

Answer 27

* Duplicated chromosomes line up around the middle of the cell. * It ensures that each duplicated pair can easily part to opposite sides of the cell

Question 28

What occurs in Anaphase?

Answer 28

* The chromosomes ( and all duplicated material) are pulled apart by the centriole spindles to opposite poles

Question 29

What occurs during Telephase?

Answer 29

* Chromosomes complete their journey to the poles * Nuclear envelope reforms around each set of chromosomes, briefly creating a cell with 2 nuceli. * In late telephase, cytokinesis occurs (the cell splits in two)

Question 30

A cell has twice as many mitochondria as a typical cell. It also has a large amount of rough ER. What functions might the cell have?

Answer 30

* Produce a lot of energy * Produce proteins

Question 31

what is the formula for circumfrence?

Answer 31

3.14 x *diameter*

Question 32

What happens if mitosis occurs in an uncontrolled manner in the body?

Answer 32

Mutations and cancer can occur

Question 33

What color did the agar cube turn in the diffusion experiment?

Answer 33

Pink

Question 34

Why did the agar cube change color?

Answer 34

Because the agar cubes are infused with phenopthalein and when you put them in a NaOH solution, the interaction causes them to change color.