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Cell Structure - Multiple Choice Questions 1 In which organelles is DNA present?

A nucleus and ribosomes

B chloroplasts and mitochondria

C mitochondria and lysosomes

D chloroplasts and ribosomes

2 What is the function of the organelles labelled A in the photomicrograph below?

A They form the basal bodies of cilia.

B They synthesise microtubules of the spindle.

C They are involved in muscle contraction.

D They provide routes along which materials move.

3 Which of the following is/are the most likely direct consequence(s) for a cell lacking functional Golgi

complexes?

1. The cell dies because it is unable to make glycoproteins to detect stimuli from its environment. 2. The cell dies from a lack of enzymes to digest food taken in by endocytosis. 3. The cell dies from the accumulation of worn-out organelles within itself. 4. The cell is unable to reproduce itself. 5. The cell is unable to export its enzymes or peptide hormones.

A 1 and 5

B 2 and 3

C 1, 2, 3 and 4

D 1, 2, 3 and 5

4 Which observation indicated that facilitated diffusion of a substance was taking place?

A The substance was moving down its concentration gradient much faster than expected.

B The substance was moving against its concentration gradient only when ATP was present.

C The substance was moving down its concentration gradient at a decreasing rate.

D The substance was moving against its concentration gradient only when certain proteins were present in the cell membrane.

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5 The diagram shows the structure of a typical plant cell. Which cell component is also present in prokaryotes?

6 Which of the following correctly identifies organelles containing phospholipids, RNA and DNA?

phospholipids DNA RNA

A ribosome chloroplast nucleus

B nucleus mitochondrion ribosome

C ribosome nucleus rough endoplasmic reticulum

D lysosome ribosome nucleus

7 Which of the following is not part of the endomembrane system of eukaryotic cells?

i Smooth endoplasmic reticulum ii Polyribosomes iii Lysosome iv Nucleus v Mitochondria vi Centrioles vii Golgi apparatus

A i, ii, iv and vii

B ii, iv and v

C ii, v and vi

D iv, v and vii

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The table gives the descriptions of four membranous structures in a cell. Which structure is correctly matched to its function?

Function Structure

A Packing of proteins A network of tubes and sacs, each tube and sac surrounded by a single membrane.

B Aerobic respiration An organelle bounded by two membranes, the inner being highly folded.

C Protein synthesis An organelle bounded by one membrane, containing hydrolytic enzymes.

D Lipid synthesis A stack of elongated, curved sacs, each sac surrounded by a single membrane.

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9 Which of the following pathways is MOST likely taken by newly synthesized histones?

A Rough endoplasmic reticulum Golgi complex secretory vesicle

B Rough endoplasmic reticulum Golgi complex nucleus

C Rough endoplasmic reticulum smooth endoplasmic reticulum nucleus

D Cytoplasm nucleus

10 The diagram below represents an electron micrograph of a secretory cell from a mammal. If the cell

was supplied with certain amino acids containing radioactive sulphur atoms, in which of the following structures would the earliest concentration of radioactivity appear?

11 Cells can be ruptured and their contents collected after a series of centrifugation at different speeds.

The largest components sediment and form a pellet at a relatively slow speed. The supernatant is then centrifuged at a greater speed than previously and more sedimentation into pellets occurs. The process is repeated as outlined in the following diagram.

The sequence of pellets obtained in tubes 1, 2, 3 and 4 would be

A ribosomes, endoplasmic reticulum, mitochondria, nuclei.

B ribosomes, mitochondria, nuclei, endoplasmic reticulum.

C nuclei, mitochondria, endoplasmic reticulum, ribosomes

D nuclei, endoplasmic reticulum, ribosomes, mitochondria.

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12 Some organisms change the composition of their membranes to maintain membrane fluidity when temperature changes.

Which changes occur in the composition of membranes following a change to low temperature?

A Increase phospholipids, decrease cholesterol

B Increase saturated fatty acids, increase cholesterol

C Increase unsaturated fatty acids, increase cholesterol

D Increase saturated fatty acids, decrease cholesterol

13 Fig. 20 shows the fusion of cell membranes containing rat antigens and human antigens. The distribution of the antigens from the resulting cell is also shown.

Fig. 13

Which of the following features of cell membrane does this experiment illustrate?

A Membranes are fluid.

B Membranes are made up of phospholipids.

C Membranes contain both hydrophobic and hydrophilic regions.

D Membranes form effective barriers between the internal and the external surroundings.

14 A strain of African Clawed Toad, Xenopus laevis, exists in which there is only one nucleolus in the

nucleus of each cell instead of the usual two. When such animals are mated, approximately one quarter of the offspring have two nucleoli per nucleus, one half have one nucleolus per nucleus, and one quarter have no nucleoli at all. Tadpoles without nucleoli die about four days after hatching because they lack

A centrioles and are unable to undergo cell division.

B Golgi apparatus and are unable to secrete metabolites.

C ribosomes and are unable to manufacture proteins.

D yolk and are unable to feed.

15 Which process would allow the movement of large protein molecules out of the cell?

A Active Transport

B Exocytosis

C Facilitated Diffusion

D Phagocytosis

Rat antigen

Human antigen

= +

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16 The diagram shows part of a cell surface membrane.

What is the correct function for each of the structures labelled?

regulates

membrane fluidity

forms hydrogen bonds with water to stabilise

membrane

transports ions and large polar molecules

A R R Q

B P Q R

C Q R P

D R P Q

17 The figure shows an electron micrograph of a cell.

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18 The cells of the marine algae Halicystis ovalis have large central vacuoles. The table shows the concentrations of certain ions in sea-water and in these vacuoles.

Ions Sea-water concentration / mM

Vacuole concentration / mM

Na+ K+ Cl-

Ca2+ Mg2+

488 12

523 12 34

257 337 543 2

Trace

Which statement is supported by the data in the table?

A Cations diffuse into the cell more readily than anions.

B Halicystis uses chloride in greater quantities than sodium.

C Magnesium is not used by Halicystis.

D The algae maintain a high concentration of potassium against a concentration gradient.

19 The diagram below shows a section of a cell surface membrane

Which of the following statements are correct?

I Structure A is found only on the extracellular surface of the membrane.

II Structure B may contain a channel that is hydrophobic to allow ions to move across the membrane.

III Structure B is able to bind to certain substances and change its conformation to transport these substances into the cell.

IV Structure C is able to change the structure of substances such that the substance can now diffuse across the membrane.

V Structure D is found only on one surface of the membrane.

A I, II, III and IV

B II, III and V

C I and III only

D I and V only

A

B

C

D

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20 Membranous sacs containing products of metabolism are formed by the endoplasmic reticulum in cells. Where are these products used?

A inside and outside the cell

B inside lysosomes only

C inside the cell only

D outside the cell only

Structured Questions

1 Fig. 1.1 is a micrograph of part of a plant cell.

Fig 1.1

(a) Name the structures P to R. [3]

P :

Q:

R:

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(b) Suggest why plant cells with chloroplasts also contain mitochondria. [3]

(c) State two ways in which chloroplast and mitochondria are

(i) Similar in structure [2]

(ii) Different in structure [2]

[Total:10 ]

2 (a) Fig 2.1 is an electron micrograph of an organelle. This organelle is present in large numbers in muscle cells.

Fig. 2.1

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(i) The scale bar represents an actual length of 2 m. Calculate the magnification of the drawing and show your working. [2]

(ii) Explain why muscle cells contain large numbers of this organelle. [2]

(b) Muscle cells are examples of eukaryotic cells. Bacterial cells are examples of prokaryotic cells.

State four ways in which the structure of muscle cells differ from bacterial cells. [4]

[Total:8] 3 Fig 3.1 shows part of an animal cell as seen through an electron microscope.

Fig 3.1

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(a) (i) Identify structures A to D. [2] A:

B:

C:

D:

(ii) Identify and describe the function of X. [3]

(iii) Explain how X is adapted to its function. [2]

(b) Membranes of A, C and X share the same basic structure.

(i) Describe the basic structure of these membranes. [2]

(ii) Explain how the membranes differ in structure for A, C and X to perform different functions. [2]

[Total: 11]

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4 Fig 4.1 shows two organelles that are found in a cell.

Fig 4.1

(a) Identify organelles A and B. [1] A:

B:

(b) Describe two ways in which organelle A is similar to B. [2]

(c) Explain the function of organelle A and B with relation to the synthesis of a protein found on the

plasma membrane. [4]

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(d) The passage of most molecules through membranes is regulated by proteins. Fig. 4.2 shows four main steps in the release of insulin from beta cells, which involves three types of transmembrane proteins.

Fig 4.2

Explain why transmembrane proteins are necessary for glucose, postassium ions and calcium ions to pass through the cell surface membrane. [2]

(iii) Explain why a Na+/K+ pump requires a catalytic site for its function. [3]

[Total: 9]

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5 (a) Glycoproteins are found in cell surface membranes. In human circulatory system, old red blood cells are removed and taken in by liver cells. This is facilitated by glycoproteins found on the cell surface membrane of red blood cells. Fig 5.1 shows the structure of glycoproteins found in membranes of new and old red blood cells.

(i) With reference too Fig 5.1, suggest how liver cells are able to identify old red blood cells and remove them from circulation. [2]

(ii) Suggest how glycoproteins like this are embedded in the cell surface membrane. [2]

Fig. 5.1

red blood cell membrane

glycoprotein

Old red blood cell As the red blood cell circulates in the bloodstream, enzymes on the inner surface of blood vessles remove terminal sialic acid, exposing galactose.

New red blood cell Glycoprotein contains sugar chains with terminal sialic acid.

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(iii)Suggest why molecules involved in cell-cell recognition are made of sugar units instead of amino acids. [2]

(b) Fig 5.2 shows a section of a cell surface membrane.

Fig. 5.2

(i) Name the molecular composition of the structures labeled L and M. [2]

(ii) Name structure N and explain its role in the cell surface membrane. [3]

[Total: 11]

M N

L

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Essays

1 (a)

(b)

(c)

Explain how the molecular structure of phospholipids is related to their function in the membrane. [6]

Relate the structure of the following organelles to the synthesis and secretion of proteins out of the cell:

(i) rough endoplasmic reticulum; and

(ii) Golgi apparatus. [8]

Describe how the structure of the membrane affects the movement of substances into and out of a cell. [6]

2 (a) Explain how lysosomes differ from ribosomes. [6]

(b)

(b)

Describe the main structural features of rough endoplasmic reticulum, mitochondrion and ribosomes. [6]

Outline the functions of rough endoplasmic reticulum, mitochondrion and ribosomes. [8]