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

Transcription

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

2 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?

3 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? nucleus 2. 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.

4 In the factory is like a plant cell wall analogy model, what is like the: 1. Cell wall 2. Nucleus 3. Mitochondrion 4. Ribosome 5. Endoplasmic reticulum

5 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)

6 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?

7 δ- δ+ 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 δ+ 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

8 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

9 δ+ δ+ 1. Draw a water molecule (and label the atoms) δ- δ+ δ- δ+ 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

10 1. Name the type of bonds shown between the water molecules. δ- 2. Describe this bond-type (remember, it does not represent a shared pair of electrons) δ+ δ + δ + δ- δ+ δ- 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?

11 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

12 1. Describe the path of H 2 0 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.

13 4. Explain the direction of gas diffusion into and out of the leaves. CO 2 is a reactant in photosynthesis and O 2 is a product 1. Describe the path of H 2 0 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. CO 2 in, O 2 out

14 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.

15 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.

16 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? Stoma 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: H 2 O, CO 2, O 2?

17 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 Stoma 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: H 2 O, CO 2, O 2? CO 2 in and H 2 O and O 2 out

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

19 Diameter = 0.4 mm # stomata π(r) 2 6 stomata = 6 stomata π(0.2 mm) mm 2 = 48 stomata/mm 2

20 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: Diameter = 0.2 mm 4. Calculate the stomatal density by # of stomata divided by the area of the circle, give your answer with the units stomata/mm 2

21 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: mm Diameter = 0.2 mm 4. Calculate the stomatal density by # of stomata divided by the area of the circle, give your answer with the units stomata/mm stomata/mm 2

22 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 [ ].

23 1. The process being shown is called diffusion. 2. Is it active (requiring ATP) or passive? passive 3. 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 [ ].

24 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?

25 1. If each square is 1 cm by 1 cm, what is the area of the 3x3 grid shown (include units)? 9cm 2 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 9cm 2 = 54 cm 2 4. What would the volume of the cube be (include units) 3cm x 3cm x 3cm = 27cm 3 5. What would be the surface area to volume ratio? 54 27=2

26 Cube sidelength (cm) Effect of Cell Size on S.A.:V. and Diffusion Surface Area (cm 2 ) Volume (cm 3 ) S.A.:V. (S.A. V.) Distance to center of cell (cm)

27 Cube sidelength (cm) Effect of Cell Size on S.A.:V. and Diffusion Surface Area (cm 2 ) Volume (cm 3 ) S.A.:V. (S.A. V.) Distance to center of cell 1 6(1)=6 1 3 =1 6 1=6 0.5 cm 2 6(4)= =8 24 8=3 1 cm 3 6(9)= = =2 1.5 cm

28 Cell Size (side length) (Cm) Area of One Face (Cm 2 ) Total Surface Area (S.A.) of Cell (Cm 2 ) Volume V.) of the Cell (Cm 3 ) Distance from Edge to Center (cm) Surface Area to Volume Ratio (S.A. V.) 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:

29 Cell Size (side length) (Cm) Area of One Face (Cm 2 ) Total Surface Area (S.A.) of Cell (Cm 2 ) Volume V.) of the Cell (Cm 3 ) 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 = /27= 2 4 (4x4)=16 6 x 16 = 96 4x4x4= 64 4/2 = 2 96/64= (5x5)=25 6 x 25 = 150 5x5x5= 125 5/2 = /125= 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.

30 Why are Cells so Small?

31 Why are Cells so Small? The smallest cube (cell) has the highest surface area to volume ratio; thus most efficient diffusion

32 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?

33 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.

34 1. What is the function of our small intestine? 2. How do villi and microvilli affect the surface area of the small intestinelining? 3. How does the small intestine construction (villi and microvilli) affect the efficiency of nutrient-absorption?

35 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.: 200m 2, similar to tenniscourt 3. How does the small intestine construction (villi and microvilli) affect the efficiency of nutrientabsorption? Dramatically increases the efficiency of nutrientabsorption allowing us to extract much of the nutrients and energy from the food we eat

36 A B 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?

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

38 How can cells increase their surface area?

39 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

40 The solute (large purple molecule) is the sugar glucose 1. 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:

41 1. 1 solute molecule on the L. and 3 on the R. 2. H 2 O molecules are attracted to solute molecules: 27 free H 2 O on the L. and 8 free H 2 O on the R. 3. Water will move L. to R. from an area of [free water] to [free water]