Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > Topic 2A: Cells Exam Questions > Flashcards

Topic 2A: Cells Exam Questions Flashcards

1
Q

Describe the structure and function of the nucleus. [4]

A

Structure:
1. Nuclear envelope and pores;
2. Chromosomes/chromatin OR DNA with histones;
3. Nucleolus/nucleoli;

Function:
4. (Holds/stores) DNA/genetic information which codes for polypeptide production OR (DNA is) code for polypeptides;
5. DNA replication (occurs);
6. Production of mRNA/tRNA OR Transcription (occurs);
7. (Nucleoli) produce rRNA/ribosomes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Eukaryotic cells produce and release proteins.

Outline the role of organelles in the production, transport and release of proteins from eukaryotic cells.

Do not include details of transcription and translation in your answer. [4]

A
  1. DNA in nucleus is code (for protein);
  2. Ribosomes/rough endoplasmic reticulum produce (protein);
  3. Mitochondria produce ATP (for protein synthesis);
  4. Golgi apparatus modify;
  5. Vesicles transport;
  6. (Vesicles) fuse with cell(-surface) membrane.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the three functions of the Golgi apparatus in a eukaryotic cell. [3]

A
  1. Modify/package/transport proteins;
  2. Modify/package/transport lipids;
  3. Forms vesicles/lysosomes.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Compare and contrast the structure of mitochondria and chloroplasts. [4]

A

Similarities:
1. Double membrane;
2. Both contain (circular) DNA;
3. Both contain ribosomes;

Differences:
4. Thylakoids/grana vs cristae;
5. Stroma vs matrix;
6. Pigment vs no pigment;
7. Starch grains vs no starch grains.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

A lack of certain inorganic ions can cause chloroplasts to contain less thylakoids membrane than normal.

Suggest why this deficiency will cause plants to have a reduced growth rate. [3]

A
  1. Smaller surface area / less chlorophyll;
  2. (So) reduced light absorption;
  3. (So) slower rate of photosynthesis.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

State in which process ribosomes are important. [1]

A
  1. Protein synthesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

State the organelle that is being referred to in each of the following descriptions:
a. It possesses structures called cristae.
b. It contains chromatin.
c. It synthesises glycoproteins.
d. It digests worn out organelles.

A

a. Mitochondria
b. Nucleus
c. Golgi apparatus
d. Lysosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Give one feature found in all prokaryotic cells that is not found in eukaryotic cells. [1]

A
  1. Circular/loop of DNA in cytoplasm / DNA free in cytoplasm / DNA not associated with proteins/histones / Murein in cell wall / smaller ribosomes in cytoplasm / only have smaller ribosomes / no membrane-bound organelles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Give two structures found in all prokaryotic cells and in all eukaryotic cells. [2]

A
  1. Cell(-surface) membrane;
  2. Ribosomes;
  3. Cytoplasm;
  4. DNA.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Contrast the structure of a bacterial cell and the structure of a human cell. [5]

A
  1. Bacterial cell is much smaller than a human cell;
  2. Bacterial cell has a cell wall but a human cell does not;
  3. Bacterial cell lacks a nucleus but human cell has a nucleus;
  4. Bacterial cell lacks membrane-bound organelles but human cell has membrane-bound organelles;
  5. Bacterial ribosomes smaller than human ribosomes (in cytoplasm);
  6. Bacterial DNA is circular but human DNA is linear;
  7. Bacterial DNA is not bound to protein whereas human DNA is bound to histones/proteins.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

DNA and RNA can be found in bacteria.

Give two ways in which the nucleotides in DNA are different from the nucleotides in RNA. [2]

A
  1. DNA contains thymine and RNA contains uracil;
  2. DNA contains deoxyribose and RNA contains ribose.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe how lactose is formed and where in the cell it would be attached to a polypeptide to form a glycoproteins. [4]

A
  1. Glucose and galactose;
  2. Joined by condensation (reaction);
  3. Joined by glycosidic bond;
  4. Added to polypeptide in Golgi (apparatus).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Name the process by which prokaryotic cells divide. [1]

A
  1. Binary fission
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Give the function of a mitochondrion. [1]

A
  1. The site of aerobic respiration (reactions)

OR

ATP is made.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Milk is produced and secreted by gland cells. These gland cells have adaptations that include many mitochondria and many Golgi vesicles. The milk contains a high concentration of protein.

Explain the role of these cell adaptations in the production and secretion of milk. [2]

A
  1. (Many mitochondria) release energy / ATP for movement of vesicles/synthesis of protein/active transport;
  2. (Many Golgi) vesicles transport protein/glycoprotein/milk to cell membrane/out of cell.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the differences between an optical microscope and an electron microscope. [5]

A
  1. Uses light vs uses electrons;
  2. Lower resolution vs higher resolution;
  3. Only larger organelles can be observed and organelles are seen in less detail vs smaller organelles can be observed and organelles can be seen in more detail;
  4. Can be used on living or dead specimens vs specimen will be dead;
  5. Can show colour vs does not show colour;
  6. Less time-consuming/complex preparation vs more time-consuming/complex preparation;
  7. Focuses using glass lenses vs focuses using magnets.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe how a sample of chloroplasts could be isolated from leaves. [4]

A
  1. Break open cells/tissue and filter
    OR Grind/blend cells/tissue/leaves and filter;
  2. In cold, same water potential/isotonic, pH controlled/buffered solution;
  3. Centrifuge/spin and remove nuclei;
  4. (Centrifuge/spin) at high(er) speed, chloroplasts settle out.
18
Q

Name two structures present in plant cells that are not present in animal cells. [1]

A
  1. Chloroplasts / cell wall / cell vacuole / starch grains
19
Q

Explain why, when fractionating organelles, an ice-cold, buffered, isotonic solution is used. [3]

A
  1. Ice-cold - slows/stops enzyme activity to prevent digestion of organelles;
  2. Buffered - maintains pH so that enzymes/proteins are not denatured;
  3. Isotonic - prevents osmosis so no lysis/shrinkage of organelles.
20
Q

Explain why, when fractionating organelles, a blender is used and then the mixture is filtered. [2]

A
  1. Break open cells / homogenise;
  2. Remove unbroken cells / larger debris.
21
Q

Name the organelle that makes up most of the first pellet after centrifuging at a lower speed. [1]

A
  1. Nucleus / nuclei
22
Q

During organelle fractionation, the second centrifuge tube was spun at a higher speed to obtain the next sample of organelles.

Suggest why. [1]

A
  1. Less dense than nucleus
23
Q

The detail shown in a diagram of a chloroplast using an electron microscope would not be seen using an optical microscope.

Explain why. [2]

A
  1. Light has long(er) wavelength;
  2. (So) low(er) resolution.
24
Q

Name an organelle found in both a chloroplast and a prokaryotic cell. [1]

A
  1. (Smaller) ribosomes
25
Q

Describe and explain how centrifuging a culture of bacteria allows scientists to obtain a cell-free liquid. [3]

A
  1. Large/dense/heavy cells;
  2. Form pellet / move to bottom of tube (when centrifuged);
  3. Liquid/supernatant can be removed.
26
Q

Give one function of lysosomes. [1]

A
  1. Break down cells/cell parts/toxins.
27
Q

H. pylori cells (the type of bacterium that causes stomach ulcers) produces an enzyme that neutralises acid.
Suggest one advantage to the H. pylori of producing this enzyme. [2]

A
  1. To stop/reduce them being damaged/destroyed/killed;
  2. By stomach acid.
28
Q

Describe how you could make a slide with a piece of plant tissue to observe the position of starch grains in the cells when using an optical microscope. [4]

A
  1. Add drop of water to (glass) slide;
  2. Obtain thin section (of plant tissue) and place in slide / float on drop of water;
  3. Stain with/add iodine in potassium iodide;
  4. Lower cover slip using mounted needle.
29
Q

State how you can identify if an image has been made using a transmission electron microscope. [2]

A
  1. High resolution;
  2. Can see internal structure of organelles.
30
Q

Describe how phospholipids are arranged in a plasma membrane. [2]

A
  1. Bilayer;
  2. Hydrophobic/fatty acid/lipid (tails) to inside;
  3. Polar/phosphate group/hydrophilic (head) to outside.
31
Q

Describe how the rough endoplasmic reticulum (RER) is involved in the production of enzymes.

A
  1. (Rough endoplasmic reticulum has) ribosomes;
  2. To make protein (which an enzyme is).
32
Q

Describe how the Golgi apparatus is involved in the secretion of enzymes. [1]

A
  1. Modifies (protein)
    OR
    Packages/puts into (Golgi) vesicles
    OR
    Transport to cell surface.
33
Q

Student performing CPAC Practical 2 often obtain different mitosis indices for their garlic. Suggest why. [2]

A
  1. (Garlic roots) are a different age;
  2. (Root tips) from different (garlic) plants/bulbs/species;
  3. Single field of view is not representative of a root tip;
  4. Cells undergo mitosis at different times/rates.
34
Q

Give two process which occur during interphase that enable cell division to occur. [2]

A
  1. Increase in volume of cell/volume of cytoplasm / increase in mass;
  2. Increase in number of organelles;
  3. Synthesis of protein;
  4. DNA replication;
  5. ATP synthesis / respiration.
35
Q

Describe and explain what the student should have done when counting cells to make sure that the mitosis index he obtained for this root tip was accurate. [2]

A
  1. Examine large number of fields of view;
  2. To ensure representative sample;

OR

  1. Repeat count;
  2. To ensure figures are correct;

OR

  1. Method to deal with part cells shown at edge/count only whole cells;
  2. To standardise counting.
36
Q

What is a tumour? [2]

A
  1. Mass of cells/tissue
    OR
    Abnormal cells/tissue;
  2. Uncontrolled mitosis/cell division.
37
Q

Describe how you would determine a reliable mitotic index from tissue observed with an optical microscope. [3]

A
  1. Count cells in mitosis in field of view;
  2. Divide this by total number of cells in field of view;
  3. Repeat many/at least 5 times
    OR Select fields of view at random.
38
Q

Describe and explain how the DNA content of a cell halves during cell division. [3]

A
  1. Spindle fibres shorten during anaphase;
  2. Separating the (sister) chromatids (to opposite poles of the cell for the new daughter cells);
  3. Cytokinesis halves the DNA content per cell.
39
Q

Describe binary fission in bacteria. [3]

A
  1. Replication of (circular) DNA;
  2. Replication of plasmids;
  3. Division of cytoplasm (to produce daughter cells).
40
Q

Describe viral replication. [3]

A
  1. Attachment proteins attach to receptors;
  2. (Viral) nucleic acid enters cells;
  3. Nucleic acid replicated in cell;
  4. Cell produces (viral) protein/capsid/enzymes;
  5. Virus assembled and released (from cell).

Biology (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions