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1 CELL BIOLOGY PROKARYOTIC and EUKARYOTIC SP/1. SP/2. SP/4. Plant and animal cells both have A. ribosomes, cell walls and mitochondria. B. Golgi apparatus, chromosomes and mitochondria. C. Golgi apparatus, cell walls and ribosomes. D. large vacuoles, cell membranes and mitochondria. Prokaryotic and eukaryotic cells all have A. circular chromosomes. B. an endoplasmic reticulum. C. membrane bound nuclei. D. a cell membrane and ribosomes. Which of the following cell structures does not have membranes? A. Ribosomes B. Mitochondria C. Chloroplasts D. Golgi apparatus 98/1. Which function is carried out by the Golgi apparatus? A. Modification of proteins for secretion B. Synthesis of proteins C. Digestion of proteins D. Endocytosis 99/2. What is the size range of most viruses? A. 0.01 0.5 nm B. 1 5 nm C. 10 200 nm D. 0.5 1 μm 99/3. What is a function of the rough endoplasmic reticulum? A. It provides a site for transcription. B. It provides a surface for the reactions of the Krebs cycle. C. It separates positive and negative charges in the cell. D. It provides a site for protein synthesis. 99/4. What is a similarity between eukaryotic and prokaryotic cells? A. They both have chromosomes in their nuclei. B. They both have a variety of membrane-bound organelles. C. They both use DNA as their genetic material. D. They both have mitochondria for producing ATP.

2 N99/1. N99/2. Which structure is the smallest? A. A cell B. A virus C. A mitochondrion D. A bacterium Which structure is found in eukaryotic cells but not in prokaryotic cells? A. Lysosome B. Plasmid C. Cell wall D. Ribosome 00/2. Which function is carried out by the flagellum of a prokaryote? A. Movement of food towards the cell B. Movement of the whole cell from one place to another C. Movement of naked nucleic acid inside the cell D. Movement of water around the cell to speed up gas exchange N00/2. N01c/2. N01/3. N01/4. Which of these functions are carried out by the plant cell wall? I. Providing support to the cell and to the plant II. Controlling the diffusion of solutes into and out of the cell III. Active transport of mineral nutrients into the cell A. I only B. I and II only C. II and III only D. I, II and III Which statement correctly describes the Golgi apparatus? A. It is found in prokaryotic and eukaryotic cells. B. It is composed of a stack of disc-shaped structures. C. It is only found in plant cells. D. It is situated within the endoplasmic reticulum. A structure is seen in an electron micrograph of an animal cell. Its membrane appears to be continuous with the nuclear membrane and resembles a series of flattened sacs. What is this structure? A. The endoplasmic reticulum B. The Golgi apparatus C. A mitochondrion D. A chloroplast In viewing an electron micrograph of a cell, ribosomes, a slime capsule and a single circular chromosome are observed. What other structure is likely to be seen? A. The rough endoplasmic reticulum (rough ER) B. Mitochondria C. A nuclear membrane D. A plasmid

3 02/2. Which is mainly responsible for maintaining the structure of a cell membrane? A. Water B. Phospholipids C. Triglycerides D. Proteins N02/1. N02/3. What is the correct order of increasing size for the following biological structures? I. The diameter of a virus II. The diameter of a bacterium III. The thickness of a cell surface membrane IV. The diameter of a eukaryotic cell A. I < III < II < IV B. I < III < IV < II C. III < I < II < IV D. III < II < I < IV Which structure is only found in plant cells? A. Mitochondrion B. Cell membrane C. Chloroplast D. Golgi apparatus 03/1. Which characteristic applies to all prokaryote cells? A. They have a nucleus. B. They have chlorophyll. C. They have mitochondria. D. They have ribosomes. 03/3. Which structural feature(s) is/are characteristic of viruses? I. DNA or RNA II. A protein coat III. Ribosomes A. I only B. I and II only C. II and III only D. I, II and III 03/4. What is the function of the lysosome in cells? A. Digestion of substances B. Manufacture of food storage molecules C. Release of energy D. Manufacture of proteins N03/3. Which cellular structure(s) is (are) found in both a plant cell and an animal cell? I. Cell wall II. Chloroplast III. Mitochondrion A. I only B. I and II only C. I and III only D. III only

4 N03/4. N03/5. M04/1. M04/2. How do the ribosomes of prokaryotic and eukaryotic cells differ? A. Their size B. Their function C. The raw materials they utilize D. The process by which they are synthesized Which of the following is not found in a prokaryotic cell? A. Cytoplasm B. A nuclear membrane C. DNA D. Enzymes What is the term used to describe the minimum distance that two points can be distinguished as separate? A. Compound B. Magnification C. Resolution D. Nanometre In which list are the items correctly ordered, from smallest to largest? A. molecules, membrane thickness, viruses, bacteria B. molecules, viruses, bacteria, membrane thickness C. cells, viruses, organelles, membrane thickness D. cells, organelles, viruses, membrane thickness The following diagram of a prokaryote refers to questions 3 and 4. M04/3. M04/4. What is the function of structure II? A. Passing of hereditary information to offspring B. Movement of the organism C. Regulation of the entry and exit of materials D. Production of proteins Which structures are found in all eukaryotic and prokaryotic cells? A. I and II only B. II and IV only C. II and V only D. III and V only

5 N04/1. What are visible under an electron microscope but not under a light microscope? A. Bacteria B. Nuclei C. Sugar molecules D. Viruses N04/2. If a red blood cell has a diameter of 8 µm and a student shows it with a diameter of 40 mm in a drawing, what is the magnification of the drawing? A. x 0.0002 B. x 0.2 C. x 5 D. x 5 000 N04/4. The diagram shows part of an animal cell as seen in an electron micrograph. What is the structure labelled X? A. Golgi apparatus B. Lysosome C. Mitochondrion D. Nucleus M05tz1/2. A photomicrograph of a tissue is accompanied by a scale bar which represents 1 µm. The scale bar is 10 mm long. What is the magnification of this photomicrograph? A. x 10 B. x 1 000 C. x 10 000 D. x 1 000 000 M05tz1/6. A cell has a high density of rough endoplasmic reticulum (ER) in its cytoplasm. Which other organelle can be expected to occur in large numbers in this cell? A. Chloroplasts B. Microvilli C. Golgi apparatus D. Nuclei

6 N05/1. N05/2. N05/3. Which functions of life are carried out by unicellular organisms? A. Nutrition but not reproduction B. Nutrition and reproduction, but not excretion C. Nutrition, reproduction and excretion but not transmission of nerve impulses D. Nutrition, reproduction, excretion and transmission of nerve impulses What is a function of the bacterial cell wall? A. Absorption of glucose by active transport B. Exchange of plasmids between cells C. Increasing the surface area for oxygen diffusion D. Preventing internal pressures from bursting the cell What is a difference between prokaryotic and eukaryotic cells? A. DNA in eukaryotes is associated with protein but in prokaryotes it is not. B. Prokaryotic cells respire anaerobically using mitochondria but eukaryotic cells do not. C. Prokaryotic cells have 80S ribosomes whereas eukaryotic cells have 70S ribosomes. D. Eukaryotic cells have enzymes in their cytoplasm but prokaryotic cells do not. M06tz1/1. Which of the labelled parts on the diagram of the prokaryote is the nucleoid? A. I B. II C. III D. IV M06tz1/2. How are all cells formed? A. By mitosis B. By cell division C. By meiosis D. By fragmentation M06tz2/2. The width of a human hair is 0.1 mm. What is the width in μm? A. 10 μm B. 100 μm C. 1000 μm D. 10 000 μm Ν06/1. Which ratio limits the size of cells? A. The rate of metabolism to mass B. The surface area to volume C. The mass to volume D. The surface area to mass

7 M07/1. M07/2. M07/3. N07/1. N07/4. Which structure is found in all prokaryotic cells? A. Flagella B. Ribosomes C. Mitochondria D. Vacuoles Which combination of features is found in most plant and animal cells? A. plasma membrane, lysosome, Golgi apparatus B. cytoplasm, mitochondria, ribosomes C. rough ER, nucleus, centrioles D. plastids, cytoplasm, nucleus What is the size range for the diameters of most plant and animal cells? A. 100 nm to 1 μm B. 1 μm to 10 μm C. 10 μm to 100 μm D. 100 μm to 1 mm What advantages does electron microscopy have over light microscopy? I. Excellent resolution throughout magnification range. II. Biological material is easy to prepare and stain. III. Movement of living cells can be seen. A. II and III only B. I and II only C. I only D. III only Viruses have a non-cellular structure. What components make up their structure? A. Lipid bilayer surrounding cytoplasm B. Lipid bilayer surrounding DNA or RNA C. Protein coat surrounding DNA or RNA D. Protein coat surrounding active mitochondria

8 MEMBRANES and TRANSPORT N99/3. The cells of plant roots can take up ions from the soil against the concentration gradient. What is the process used? A. Osmosis B. Passive transport C. Diffusion D. Carrier-assisted transport 00/3. What is needed for osmosis to occur? I. a concentration gradient of solutes II. a partially permeable membrane III. a supply of ATP A. I only B. I and II only C. I and III only D. I, II and III N00/3. The table shows the normal concentration of two ions in red blood cells and in the surrounding plasma: concentration / mm dm -3 Ions Red blood cells Blood plasma Potassium (K + ) 150 5 Sodium (Na + ) 26 144 What does this information show? A. Sodium is actively transported out of the cell. B. Sodium is transported out of the cell by diffusion, but potassium does not move. C. Sodium moves into the red blood cells by diffusion and the potassium moves out by diffusion. D. Osmosis is occurring. 01/2. Cells in the placenta take in droplets of fluid from the maternal blood. Vesicles containing the fluid are formed by this process. The vesicles are visible in the cytoplasm of the placenta cells. What is the transport mechanism involved? A. Pinocytosis B. Exocytosis C. Phagocytosis D. Carrier-assisted transport

9 03/2. 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 03/5. What is essential for diffusion? A. A concentration gradient B. A selectively permeable membrane C. A source of energy D. A protein N02/4. N03/1. M04/5. Which of the following is a feature of exocytosis but not endocytosis? A. Lipid bilayer fusion B. Vesicle formation C. Lipid bilayer adhesion D. Secretion Which statement about facilitated diffusion is correct? A. It requires a protein. B. It refers to the diffusion of water. C. It requires ATP. D. It involves movement against a concentration gradient. Which structure may require ATP for its functioning?

M05tz1/3. What part of the plasma membrane is responsible for preventing the free movement of ions into and out of the cell? 10 A. I B. II C. III D. IV M05tz1/4. What is facilitated diffusion? A. The passive movement of a particle through the phospholipid bilayer of the cell membrane. B. The passive movement of a particle across a cell membrane via a channel protein. C. The movement of a particle down a concentration gradient helped by active pumping. D. The movement of a particle up a concentration gradient helped by active pumping. M05tz2/2. Which of the following is required for osmosis to occur? A. An enzyme B. A fully permeable membrane C. ATP D. A solute concentration gradient M06tz1/3. Which pair of characteristics are correct for the cellular processes of exocytosis and endocytosis? Exocytosis Endocytosis A. Secretion of cellular materials Vesicles are moved away from the plasma membrane B. Cell membranes fuse Vesicles are moved towards the plasma membrane C. Infolding of plasma membrane Vesicles are moved away from the plasma membrane Vesicles moved towards the D. plasma membrane Plasma membrane increases in size

11 M06tz2/4. What process involves the movement of a solvent through a semi-permeable membrane from a region of low solute concentration to a region of high solute concentration? A. Active transport B. Osmosis C. Simple diffusion D. Facilitated diffusion M06tz2/1. Which two molecules are the principal components of membranes? A. Glycogen and protein B. Lipid and glycogen C. Cellulose and protein D. Protein and lipid Ν06/2. Which statements are characteristics of diffusion through membranes? I. Polysaccharides can be transported. II. It can be facilitated by special channels. III. It is affected by concentration gradients. A. I and II only B. I and III only C. II and III only D. I, II and III M07/4. During endocytosis, what change will most likely occur in the plasma membrane of a cell? A. It will form two phospholipid monolayers. B. It will become electrically charged. C. It will partially dissolve. D. It will form vesicles. M07/5. Which of the following could be a function of a membrane protein? A. Energy storage B. Enzymatic activity C. Oxygen uptake D. Thermal insulation N07/2. The diagram below shows part of a plasma membrane. What label should be used for structure I? A. Peripheral protein B. Phospholipid C. Cholesterol D. Integral protein

12 MITOSIS SP/3. During mitosis A. DNA transcription and replication occur. B. two genetically identical nuclei are produced. C. replicated DNA molecules are moved to opposite ends of the cell. D. homologous chromosomes form pairs. 98/3. What is produced by mitosis? A. Two genetically identical nuclei B. Four genetically identical nuclei C. Two genetically different nuclei D. Four genetically different nuclei 98/4. In which group of organs can tumours occur? I. lung, breast, cervix and skin II. brain, bone, testis and intestine III. eye, oesophagus, thyroid gland, pancreas IV. leaf, stem and root A. I but not II, III or IV B. I and II but not III or IV C. I, II and III but not IV D. I, II, III and IV 00/4. What causes the chromosomes of an animal cell to move to opposite ends of the cell during mitosis? A. microtubules B. mesosomes C. nuclear membranes D. mitochondria 02/3. Which processes occur during interphase? I. DNA replication II. DNA transcription III. Separation of replicated DNA molecules A. I and II only B. I and III only C. II and III only D. I, II and III N02/5. Which process occurs during interphase of the cell cycle? A. Duplication of chromosomes B. Separation of chromatids C. Condensation of chromatin D. Migration of centrioles

13 03/6. Which statement best describes a role of mitosis? A. It increases genetic variation. B. It facilitates growth of unicellular organisms. C. It facilitates reproduction of some unicellular organisms. D. It repairs damaged cells. N04/5. Which phases of mitosis are shown in diagrams I and II? I II A. metaphase prophase B. metaphase telophase C. anaphase prophase D. anaphase metaphase M05tz1/5. How does mitosis produce two genetically identical nuclei? A. By separation of homologous pairs of chromosomes B. By separation of pairs of chromatids C. By division of the cytoplasm equally in two D. By division of the centrioles in two M05tz2/3. Which of the following are functions of mitosis? = yes = no Reduction in chromosome number Tissue repair A. B. C. D. N05/4. Colchicine is a chemical substance that prevents the formation of microtubules. What stage of mitosis would be prevented, if dividing cells were treated with colchicine? A. Breaking down of the nuclear membrane B. Replication of DNA C. Separation of genetically identical chromosomes (chromatids) D. Supercoiling of chromosomes

14 M06tz1/4. Which of the following processes take place during interphase? I. Respiration II. Active transport III. Protein synthesis IV. Replication of DNA A. I only B. I and II only C. I, II and III only D. I, II, III and IV Ν06/4. N07/3. Which statement is characteristic of tumours? A. They occur only in certain animal cells. B. They result from controlled cell division in only some organs. C. They result from uncontrolled cell division and occur in any organ. D. They result from partially controlled transcription. What is the product of mitosis in plant cells? A. Four daughter cells with genetically different nuclei B. Four daughter cells with genetically identical nuclei C. Two daughter cells with genetically different nuclei D. Two daughter cells with genetically identical nuclei

15 DATA BASED QUESTION(S) 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. (a) From the information in the graph alone, describe the relationship between the diameter of a molecule and its movement through a membrane. [2] 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.

16 (b) Identify the rate of glucose uptake at an external glucose concentration of 4 mmol dm -3 by (i) simple diffusion.... [1] (ii) facilitated diffusion.... [1] (c) (i) Compare the effect of increasing the external glucose concentration on glucose uptake by facilitated diffusion and by simple diffusion. [3] (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. [2]

17 ESSAY QUESTIONS Explain the importance of the surface area to volume ratio as a factor limiting cell size. [7] Explain the reasons for cells not growing to a large size, including the effects of surface area to volume relationships. [8] Draw a labelled diagram showing the ultrastructure of a typical prokaryote. [4] Draw a labelled diagram of a prokaryotic cell as seen in electron micrographs. [6] Outline the functions of the structures found in prokaryotic cells. [5] Compare the structure of prokaryotic and eukaryotic cells. [5] Draw a labelled diagram of a generalized animal cell showing the ultra structure visible using an electron microscope. [5] Define the term organelle and state one function for each of these organelles: ribosome, golgi apparatus, mitochondrion, lysosome, rough endoplasmic reticulum. [6] Distinguish between the structure of plant and animal cells. [6] Compare, with the aid of a diagram, the structure of generalised prokaryotic and eukaryotic animal cells. [8] State three differences between plant and animal cells. [3] State one function of each of the following organelles. [5] Lysosome Golgi apparatus Rough endoplasmic reticulum Nucleus Mitochondrion Compare simple diffusion with facilitated diffusion as mechanisms to transport solutes across membranes. [5] Describe the process of endocytosis. [5] Draw a labelled diagram to show the fluid mosaic structure of a plasma membrane, indicating the hydrophilic and hydrophobic regions. [5] Distinguish between active and passive movements of materials across plasma membranes, using named examples. [4] Outline how vesicles are used to transport materials secreted by a cell. [6] Explain the processes of active and passive transport that move materials across a membrane. [8] Draw and label a diagram to show the fluid mosaic model of a biological membrane. [6] List the functions of membrane proteins. [4] Explain how the structure and properties of phospholipids help to maintain the structure of cell membranes. [9] Outline the process of endocytosis. [5] Outline the structure of cell membranes, including the substances contained within them and how they are arranged. [5] Compare active transport across membranes with passive transport across membranes. [5] State what is meant by the term osmosis. [4] Compare the movement of materials across cell surface membranes by active and passive transport. [4]

18 Explain how substances may pass into cells through the membrane. [8] Explain the various methods cells use to transport materials across membranes. [8] Explain how vesicles are used in cells, including the way in which they form and are reabsorbed. [8] Explain the process of passive transport across the cell membrane. [8] Describe the events that occur during mitosis. [9] Outline one therapeutic use of stem cells. [6] Explain how mitosis produces two genetically identical nuclei. [8] Before cell division in unicellular and multicellular organisms, the nucleus must divide to produce two genetically identical nuclei. Explain the events that occur in cells that result in the production of genetically identical nuclei. [8] Suggest why cell division is necessary in multicellular organisms. [4] Draw diagrams to show the four stages of mitosis in an animal cell with four chromosomes. [5] During an infection, B-lymphocytes produce, by mitosis, clones of identical cells programmed to produce antibodies. Describe briefly the process of mitosis. [6]