B2

Question 1

4. what is the role of the nucleolus

Answer 1

manufactures ribosomal RNA (rRNA)

Question 2

10. what organelle is found in plant and algae cells but not animal cells

Answer 2

• cell wall
• vacuole
• chloroplasts

Question 3

15. what organelle is used by phagocytes to digest pathogens

Answer 3

lysosomes

Question 4

16. what organelle carries out protein synthesis

Answer 4

ribosomes

Question 5

20. what does the RER do

Answer 5

synthesises proteins

Question 6

21. what does the SER do

Answer 6

synthesises lipids

Question 7

22. what does the golgi body do

Answer 7

• modifies proteins and lipids
• forms vesicles (to transport modified proteins to cell membrane)
• forms lysosomes

Question 8

23. what is the function of a cell wall in plants

Answer 8

provides mechanical strength
prevents lysis when water enters

Question 9

38. what CANT be seen in an OPTICAL microscope but CAN be seen in an electron microscope

Answer 9

ribosomes

Question 10

39. what CAN be observed using an optical microscope that CANT be observed using an electron microscope

Answer 10

living specimen
specimen in colour

Question 11

40. why does an electron microscope have better resolution than an optical microscope

Answer 11

electrons have shorter wavelength than light

Question 12

68. what are the 3 stages of the cell cycle

Answer 12

interphase
nuclear division (mitosis/meiosis)
cytokineses

Question 13

69. what stage of the cell cycle does DNA replication happen in?

Answer 13

interphase

Question 14

70. what is replicated in interphase

Answer 14

DNA
organelles

Question 15

71. what are homologous chromosomes

Answer 15

not identical but have the same gene loci

Question 16

72. what can differ on the homologous chromosomes

Answer 16

the alleles

Question 17

73. where do the homologous chromosomes come from

Answer 17

paternal
maternal

Question 18

74. what do you call a cell that has homologous chromosomes arranged in pairs

Answer 18

diploid

Question 19

75. what do you call a cell that contains one of each homologous pair

Answer 19

haploid

Question 20

76. what are the components of chromatin

Answer 20

DNA and histone

Question 21

77. what are sister chromatids

Answer 21

genetic copies of a chromosome
attached by a centromere

Question 22

78. name the stages of mitosis

Answer 22

prophase
metaphase
anaphase
telophase

Question 23

79. how can you tell if a cell is undergoing mitosis when observing under a microscope

Answer 23

chromosomes are condensed and therefore visible
double the amount of DNA

Question 24

80. during which phase do chromosomes line up along the equator of the cell

Answer 24

metaphase

Question 25

81. during what stage are sister chromatids separated

Answer 25

anaphase

Question 26

82. what part of the cell is needed for anaphase to happen

Answer 26

mitochondria - to provide energy

Question 27

83. describe what happens in prophase

Answer 27

chromosomes condense and become visible
nuclear envelope disintegrates
nucleolus disappears

Question 28

84. describe cytokineses

Answer 28

cytoplasm and cell membrane divides
forming 2 genetically identical cells

Question 29

85. describe the behaviour of chromosomes during mitosis and explain how this results in the production of two genetically identical cells

Answer 29

1. chromosomes shorten/thicken/supercoiling
2. chromosomes (each) two identical chromatids (due to replication)
3. chromatids move to equator
4. attach to individual spindle fibres
5. spindle fibres contract/centromeres divide