Cells
Unit
Test
Time
allowed: 70 minutes
You
may use a calculator (≤ Ti 84)
Write
all answers on this paper
Section
A: Multiple Choice (16 marks)
Section B:
Structured Factual Recall (16 marks)
Section C:
Structured Data Analysis (14 marks)
Section D:
Extended Response (14 marks)
Name:
_______________________
Date:
_______________________
Score: ___/ 50
= ____ % (IB Grade ___)
Section A: Multiple Choice (circle the correct answer)
1. Which of the following is considered acellular or non-living?
A. Eukaryote cell
B. Prokaryote cell
C. Amoeba
D. Virus
2. A student observes and draws an Amoeba, using the high power lens of a microscope. The diameter of the drawing is 100 mm. The actual diameter of the Amoeba is 100 µm. What is the magnification of the drawing?
1000x
3. Which of the following are fundamental statements of cell theory?
i. Cells come only from other cells
ii. Cells maximize their SA:Vol ratio
iii. All living things consist of cells
iv. Cells are the smallest units of life
A. i and ii
B. i, iii and iv
C. ii, iii and iv
D. i, ii, iii and iv
4. What is essential for diffusion?
A. A
concentration gradient
B. A selectively permeable membrane
C. A source of energy
D. A protein
5. Which part of the plasma membrane is involved in recognition of other cells?
A. Phospholipid bilayer
B. Integral proteins
C. Peripheral proteins
D. Cholesterol
6. The diagram below shows a channel protein in a plasma membrane.
Channel proteins allow polar molecules to pass through by facilitated diffusion.
Which labeled parts of
the channel proteins are likely to be polar?
A. I and II only
B. III and IV only
C. I and III only
D. All parts
7. How do animals use cholesterol?
A. To store energy
B. To form part of the plasma membrane
C. To insulate neurons (nerve cells)
D. To increase blood pressure
8. Which cell organelle is responsible for the production of proteins to be exported from the cell?
A. Rough endoplasmic reticulum
B. Free ribsomes
C. Mitochondrion
D. Lysosome
9. Which of the following correctly describes the process of osmosis?
A. The passive movement of water molecules from areas of low solute
concentration to high solute concentration, through a selectively permeable
membrane.
B. The passive movement of water molecules from areas of high solute concentration to low solute concentration, through a selectively permeable membrane.
C. The
active movement of water molecules from areas of high solute concentration to
low solute concentration, using a
membrane pump protein.
D.
The passive movement of water molecules from areas of low solute
concentration to high solute concentration, through a channel protein.
10. During which phase of the cell cycle is the plasma membrane divided to give two new daughter cells?
A. 
Interphase
B. Prophase
C. Anaphase
D. Cytokinesis
11. Which labels match ‘i’ and ‘ii’ respectively?
A. Centromere and chromosomes
B. Centriole and chromosomes
C. Centromere and sister chromatids
D. Centriole and sister chromatids
12. In the diagram below macromolecules are being transported to the exterior of a cell.
What is the name of this
process?
A. Exocytosis
B. Pinocytosis
C. Endocytosis
D. Phagocytosis
13. If a cell plate is beginning to form and nuclei are re-forming at opposite ends of a cell, what kind of cell is this?
A. An animal cell in prophase
B. A plant cell in prophase
C. An animal cell in telophase
D. A
plant cell in telophase
14. Which of the following correctly describes exocytosis?
|
|
Plasma |
Plasma |
Membranes
fuse |
vesicles |
|
A. |
No |
Yes |
No |
Yes |
|
B. |
Yes |
No |
Yes |
No |
|
C. |
No |
Yes |
Yes |
Yes |
|
D. |
No |
No |
No |
Yes |
15. What ensures that mitosis produces two genetically identical nuclei?
A. One of each of the
twenty-three types of chromosome is pulled to each pole of the cell by spindle
microtubules.
B. Half of the chromosomes
are pulled to each centriole by mesosomes.
C. Identical
chromatids are pulled to opposite poles by spindle microtubules.
D. DNA molecules are moved
to the equator of the cell where they are replicated.
16. The DNA of a particular cell is damaged, so that the cell continues to divide uncontrollably. What is the possible result?
A. Coronary heart disease
B. AIDS
C. Tumour
formation
D. Down syndrome
End of Section A. 16 marks.
Section B: Structured Factual Recall
1.
|
a. Calculate the length of the cell ‘A’.
|
[2.2µm – 2.8µm if work shown]
b. By which method do prokaryotes reproduce?
…………Binary fission………………. (1)
2. a. Explain how the surface area to volume ratio influences cell size.
the rate of material /
heat exchange / diffusion is proportional to surface area;
the rate of metabolism is proportional to mass / volume;
as a cell grows, the volume increases faster than the surface area / as a cell
grows, surface area to volume ratio decreases;
(without cell division) material / heat cannot be exchanged fast enough to meet
the needs of the cell (3)
b. Compare prokaryotic and eukaryotic cells with regard to three features: [3 max]
Award [1]for each of the following pairs.
Mark first answer only in boxes 1, 2 and 3.
Allow [1] only for a similarity.
prokaryotic cells eukaryotic cells
nucleoid
/ no nucleus /nuclear membrane vs. nucleus / nuclear membrane;
naked DNA / no histones vs. NA with protein /histone;
no mitochondria vs. mitochondria present;
no Golgi / no ER vs. Golgi / ER present;
circular DNA vs. linear DNA;
no / very few membrane-bound organelles vs. membrane-bound organelles;
ribosomes smaller / 70S vs. ribosomes larger / 80S;
no mitosis / meiosis vs. mitosis / meiosis;
flagella lack internal microtubules vs. flagella have microtubules (9+2);
c. List functions of membrane proteins (4)
hormone
binding sites;
enzymes;
electron carriers;
channels for (passive) transport;
(pumps) for active transport;
cell to cell recognition;
receptors for neurotransmitters;
3. a. Differentiate between diffusion and osmosis.
Must have both
for [1].
diffusion is
the movement of molecules from an area of high
concentration to an area of low concentration;
osmosis is the diffusion of water across a
partially
permeable
membrane; (2)
b. An animal cell is placed in a hypotonic (very weak) sugar solution.
Will the cell increase or decrease in mass?
……………………… increase ………………………………………………………………………………………… (1)
End of Section B. 15 marks.
Section C:
Structured Data Analysis
1. Draw a labeled diagram
showing the fluid mosaic model of a biological membrane. (5)
2. A
study was carried out to determine the relationship between the diameter of a
molecule and its movement through a membrane. The graph below shows the results
of the study.
[Source: Knox, et al., Biology, Mcgraw
Hill, Sydney, 1994, page 65]
(a) From the information in the graph alone,
describe the relationship between the diameter of a molecule and its movement
through a membrane.
as the diameter
of the molecule increases the permeability / relative ability
to move decreases (accept converse);
the relationship
is logarithmic / non-linear / negative;
for molecules
above 0.6 (± 0.1) nm relative ability to move changes little /
for molecules below 0.6 (± 0.1) nm relative ability to move changes rapidly;
[2 max]
A second study was carried out to investigate the effect of passive protein channels on the movement of glucose into cells. The graph below shows the rate of uptake of glucose into
 |
erythrocytes by simple diffusion and facilitated diffusion.
(b) Identify the rate of glucose uptake at an
external glucose concentration of
4 mmol
dm-3by
(i) simple
diffusion. 10 mmol cm-3 hr-1 (accept ± 5) (1)
(ii) facilitated
diffusion. 370 mmol cm-3 hr-1 (accept ± 10) (1)
(c) (i) Compare
the effect of increasing the external glucose concentration on glucose uptake
by facilitated diffusion and by simple diffusion.
• Rate of glucose uptake in facilitated diffusion levels out as external
glucose concentration increases whereas uptake in simple diffusion does not
level out / continues to rise.
• Rate of glucose uptake increases with both increasing external
concentration in both.
• Rate of glucose uptake is higher in facilitated diffusion (than in
simple diffusion).
• Increase in rate of glucose uptake in simple diffusion is constant/
linear, whereas in facilitated diffusion the rate of uptake increases rapidly
at the beginning / increase is not constant. (3 max)
(ii) Predict,
with a reason, the effect on glucose uptake by facilitated diffusion of
increasing the external concentration of glucose to 30 mmol dm-3.
Little/ no change in glucose uptake;
… because all/most (protein) glucose channels in use (2)
End of Section C. 9 marks.
Section D: Extended Response Answer these questions on the paper provided.
1. Describe the process of active transport across membranes.
goes against concentration gradient / from low concentration
to high concentration;
requires hydrolysis of ATP / requires energy from ATP;
proteins in membrane utilized;
specificity of carriers;
eg Na+-K+ pump / other
suitable examples;
may involve conformational change in carrier protein;
moves ions / solutes;
maintains chemical / electrical gradient;
[5]
2. Draw
labeled diagrams to show the four stages of mitosis in an animal cell with 2
chromosomes. (5)
prophase showing spindle fibres;
prophase showing condensed chromatin;
prophase showing replicated chromosomes;
metaphase showing replicated chromosomes lining
up at the equator;
anaphase showing chromatids moving to opposite poles;
telophase showing nucleus reforming;
telophase showing cytokinesis occurring; 5
max
The four diagrams must have the name of the phase, otherwise
award [3 max].
The four stages must be included to receive [5]. If correct number of
chromosomes is not shown award [4 max].
Explain how mitosis ensures that daughter
cells are genetically identical. (4)
sister chromatids are two identical DNA molecules held
together by centromere;
sister chromatids are separated during mitosis to form two
genetically identical nuclei;
at start of anaphase centromeres divide separating sister
chromatids;
separated sister chromatids known as (single stranded)
chromosomes;
(identical sets of) chromosomes pulled to opposite poles;
nuclear envelope / membrane forms around each set of
chromosomes;
End of Section D. 14 marks.
----END OF TEST: CHECK YOUR WORK ---