Pre-AP Biology Unit II: Cell Structure and Function Quiz

Your kitchen is compartmentalized.

Structures within the cell, called organelles, form compartments within the cell.

1. What is an example of an organelle within the cell?

2. What is the benefit that eukaryotic cells gain from having organelles to compartmentalize within the cell?

Your kitchen is compartmentalized.

Structures within the cell, called organelles, form compartments within the cell.

1. What is an example of an organelle within the cell? nucleus2. What is the benefit that eukaryotic cells gain from having

organelles to compartmentalize within the cell? Creates different micro-environments. Incompatible tasks can occur simultaneously. Efficiency is increased.

In the factory is like a plant cell wall analogy model, what is like the:

1. Cell wall2. Nucleus3. Mitochondrion4. Ribosome5. Endoplasmic

reticulum

In the factory is like a plant cell wall analogy model, what is like the:

1. Cell wall factory walls (8) 2. Nucleus control room (1)3. Mitochondrion power

plant (3)4. Ribosome protein

manufacturer (4)5. Endoplasmic reticulum

transport (7)

1. Which atom, oxygen or hydrogen, is more electronegative?

2. What does this mean?

3. Which partial charge will oxygen and hydrogen have as a result?

4. Water is a polar molecule, what does that mean?

1. Which atom, oxygen or hydrogen, is more electronegative? oxygen

2. What does this mean? Oxygen exerts a stronger pull on the shared pair of electrons

3. Which partial charge will oxygen and hydrogen have as a result? See partial charge symbols on diagram (δ)

4. Water is a polar molecule, what does that mean? There is a partial + pole and a partial – pole

δ-

δ+

δ+

1. Draw a water molecule (and label the atoms)

2. How many electrons are being shared between the oxygen atom and one hydrogen atom?

3. Name this type of bond:

4. Is the pair of electrons being equally shared? Explain:

5. Label the atoms on your diagram with partial charges δ+ and δ-

6. Draw a second water molecule and show a hydrogen bond between the two molecules

1. Draw a water molecule (and label the atoms)

2. How many electrons are being shared between the oxygen atom and one hydrogen atom? 2

3. Name this type of bond: polar covalent

4. Is the pair of electrons being equally shared? Explain: No, oxygen is more electronegative

5. Label the atoms on your diagram with partial charges δ+ and δ-

6. Draw a second water molecule and show a hydrogen bond between the two molecules

δ-

δ+

δ-

δ+

δ+

δ+

δ-

δ +

δ+δ+

δ +δ-

δ-

1. Name the type of bonds shown between the water molecules.

2. Describe this bond-type (remember, it does not represent a shared pair of electrons)

3. Is this bond type weaker or stronger than covalent bonds?

4. What is the maximum number of this type of bond that each water molecule can form?

δ-

δ +

δ+δ+

δ +δ-

δ-

1. Name the type of bonds shown between the water molecules. Hydrogen bonds

2. Describe this bond-type (remember, it does not represent a shared pair of electrons) Electrostatic attraction between partial + and partial - charges

3. Is this bond type weaker or stronger than covalent bonds? Weaker, they break and reform

4. What is the maximum number of this type of bond that each water molecule can form? 4

1. Describe the path of H20 through a land

plant.

2. Explain why plant cells need water in

order to survive.

3. Describe the path of oxygen and carbon

dioxide movement in the leaves.

4. Explain the direction of gas diffusion into

and out of the leaves.

1. Describe the path of H20 through a land plant.

Enters roots, up stem, out stomata in leaf

2. Explain why plant cells need water in order to

survive. Chemical reactions such as photo.

3. Describe the path of oxygen and carbon dioxide

movement in the leaves. CO2 in, O2 out

4. Explain the direction of gas diffusion into and

out of the leaves. CO2 is a reactant in

photosynthesis and O2 is a product

1. Water is able to move against gravity due to ___ bonds between water molecules.

2. When water molecules “stick” to the xylem cell walls due to ___ bonds, this is called _______.

3. When water molecules “stick” to each other due to ___ bonds, pulling each other up in a long chain, this is called ________.

4. The pull of water molecules evaporating from the ______ pulls on the chain of water molecules below.

1. Water is able to move against gravity due to H- bonds between water molecules.

2. When water molecules “stick” to the xylem cell walls due to H- bonds, this is called adhesion.

3. When water molecules “stick” to each other due to H- bonds, pulling each other up in a long chain, this is called cohesion.

4. The pull of water molecules evaporating from the stomata pulls on the chain of water molecules below.

1. Name & describe two structural features of the leaf that are designed to reduce a plant’s water-loss:

2. What is the function of a terrestrial plant’s roots?

3. What is the function of plant’s xylem?

4. When a leaf is in the light, and its stomata are open, in which direction are the following moving through the stomata: H2O, CO2, O2?

Stoma

1. Name & describe two structural features of the leaf that are designed to reduce a plant’s water-loss: waxy cuticle and stomata

2. What is the function of a terrestrial plant’s roots? Absorb water from soil

3. What is the function of plant’s xylem? Transport water through plant tissues

4. When a leaf is in the light, and its stomata are open, in which direction are the following moving through the stomata: H2O, CO2, O2? CO2 in and H2O and O2 out

Stoma

Calculate the stomatal density for the slide on the left:Diameter = 0.4 mm

Diameter = 0.4 mm

# stomataπ(r)2

6 stomata = 6 stomataπ(0.2 mm)2 0.1256 mm2

= 48 stomata/mm2

Diameter = 0.2 mm

1. How many stomata do you see in this microscope view?

2. What is the formula to calculate the area of a circle?

3. Calculate the area of the circular microscope view to the left:

4. Calculate the stomatal density by # of stomata divided by the area of the circle, give your answer with the units stomata/mm2

Diameter = 0.2 mm

1. How many stomata do you see in this microscope view? 5

2. What is the formula to calculate the area of a circle? π(r)2

3. Calculate the area of the circular microscope view to the left: 0.0314 mm

4. Calculate the stomatal density by # of stomata divided by the area of the circle, give your answer with the units stomata/mm2 159 stomata/mm2

1. The process being shown is called ________.2. Is it active (requiring ATP) or passive?3. It is due to ___________ energy.4. Increasing temperature _______ the rate.5. The net direction of movement is from an area

of ____ [ ] towards an area of _____ [ ].

1. The process being shown is called diffusion.2. Is it active (requiring ATP) or passive? passive3. It is due to kinetic energy.4. Increasing temperature increases the rate.5. The net direction of movement is from an area

of high [ ] towards an area of low [ ].

1. If each square is 1 cm x 1 cm, what is the area of the 3 x 3 grid shown (include units)?

2. How many sides does a cube have?

3. If a cube was made with the grid in #1 shown on each of its faces, what would its total surface area be (include units)?

4. What would the volume of the cube be (include units)?

5. What would be the surface area to volume ratio?

1. If each square is 1 cm by 1 cm, what is the area of the 3x3 grid shown (include units)? 9cm2

2. How many sides does a cube have? 6

3. If a cube was made with the grid shown on each of its faces, what would its total surface area be (include units)? 6 x 9cm2 = 54 cm2

4. What would the volume of the cube be (include units) 3cm x 3cm x 3cm = 27cm3

5. What would be the surface area to volume ratio? 54÷27=2

Cubeside-length (cm)

Surface Area (cm2)

Volume (cm3)

S.A.:V.(S.A.÷V.)

Distance to center of cell (cm)

1

2

3

Effect of Cell Size on S.A.:V. and Diffusion

Cubeside-length (cm)

Surface Area (cm2)

Volume (cm3)

S.A.:V.(S.A.÷V.)

Distance to center of cell

1 6(1)=6 13=1 6÷1=6 0.5 cm

2 6(4)=24 23=8 24÷ 8=3 1 cm

3 6(9)=54 33=27 54÷ 27=2 1.5 cm

Effect of Cell Size on S.A.:V. and Diffusion

Cell Size (side

length)

(Cm)

Area of One

Face

(Cm2)

Total Surface Area

(S.A.) of Cell

(Cm2)

Volume V.) of

the Cell (Cm3)

Distance from

Edge to Center

(cm)

Surface Area to

Volume Ratio (S.A. ÷

V.)

3

4

5

1.What is the relationship between cell size and S.A.:V.?2.What is the relationship between cell size and distance from edge to center of

cell?3.What factors influence the efficiency of diffusion into/out of a cell.4.Describe the cell shape and size that would have the most efficient diffusion:

Cell Size (side

length)

(Cm)

Area of One

Face

(Cm2)

Total Surface Area

(S.A.) of Cell

(Cm2)

Volume V.) of

the Cell (Cm3)

Distance from

Edge to Center

(cm)

Surface Area to

Volume Ratio (S.A. ÷

V.)

3

(3 x 3)=9 6 x 9 = 54 3x3x3= 27 3/2 = 1.5 54/27= 2

4

(4x4)=16 6 x 16 = 96 4x4x4= 64 4/2 = 2 96/64= 1.5

5

(5x5)=25 6 x 25 = 150 5x5x5= 125 5/2 = 2.5 150/125= 1.21. As cell size increases, surface area to volume ratio decreases.

2.As cell size increases, the distance from the cell surface to its center increases.

3.The size of the cell (small versus large) and shape (short/fat versus long/skinny) will influence the efficiency of diffusion.

4.Small cells and long/skinny cells will be most efficient at diffusion.

Why are Cells so Small?

The smallest cube (cell) has the highest surface area to volume ratio; thus most efficient diffusion

Why are Cells so Small?

1. Describe the structure of the root-system shown above?

2. What is the function of the plant’s root system?

3. How do root hairs affect total surface area of the root system?

1. The function of roots are to absorb water and nutrients from the soil by diffusion.

2. The tap-root has finger-like root-hairs.3. Root hairs increases S.A.:V. ratio, making

diffusion more efficient.

1. What is the function of our small intestine?

2. How do villi and microvilli affect the surface area of the small intestine-lining?

3. How does the small intestine construction (villi and microvilli) affect the efficiency of nutrient-absorption?

1. What is the function of our small intestine?Nutrient-absorption (nutrients from food into the blood-stream)2. How do villi and microvilli affect the surface area

of the small intestine-lining?Dramatically increases S.A.: 200m2, similar to tennis-court3. How does the small intestine construction (villi

and microvilli) affect the efficiency of nutrient-absorption?

Dramatically increases the efficiency of nutrient-absorption allowing us to extract much of the nutrients and energy from the food we eat

1. Does A or B have a larger volume?2. Does A or B have a larger S.A.?3. Which would be more efficient at

diffusion?

A B

1. Does A or B have a larger volume? same

2. Does A or B have a larger S.A.? B3. Which would be more efficient at

diffusion? B

A B

How can cells increase their surface area?

How can cells increase their surface area? A cell of a given volume can increase its S.A. (while keeping volume the same) by stretching out to become long and skinny

The solute (large purple molecule) is the sugar glucose1. How many glucose molecules are on each side of the

membrane?2. How many “free” water molecules are on each side?3. Predict & explain the direction of water movement:

1. 1 solute molecule on the L. and 3 on the R.2. H2O molecules are attracted to solute molecules: 27 “free” H2O on

the L. and 8 “free” H2O on the R.3. Water will move L. to R. from an area of ↑ [free water] to ↓ [free

water]