Ch 2 The cell as the basic unit of life
Exercise
Multiple-choice questions (p. 2-33)
1
D
2
C
3
B
4
C
5
C
6
C
7
D
8
B
Short questions (p. 2-34)
9
HKCEE Biology 2008 I Q4
10 a
Eyepiece
Objective
Total
magnification
10X
10X
100X
10X
20X
200X
10X
40X
400X
1
b
i
ii
11
2.8 mm/7 μm
1
= 400
1
Plant cells are larger than animal cells.
1
HKALE Biology 2011 I Q3a–b
Structured questions (p. 2-35)
12 a
Advantages:
It can be used to see ultra-structures. /
It can produce images with higher magnifications. /
It can produce images with higher resolution. / It has a higher resolving
power.
(any 2)
Disadvantages:
The cost is high. /
It is difficult to operate. /
1x2
The preparation of specimens is complex. /
Living material cannot be viewed. (any 2)
b
c
13 a
b
i
47 mm
1
ii
47 mm/6800
1
= 6.91 μm
1
i
Mitochondrion
1
ii
It is the main site where respiration takes place.
1
A large vacuole / chloroplasts / cell wall (any 2)
i
b
not. 1
1x2
B
1
E
1
F
1
A
1
D
1
64/0.1
1
= 640
1
28000/2
1
= 14000
1
ii
Mitochondrion
1
iii
Mitochondria release energy by respiration.
1
Muscle cells require much energy
1
for contraction.
1
ii
14 a
1x2
i
Muscle cells have a nucleus / nuclear membrane while bacterial cells do
Muscle cells have membrane-bounded organelles while bacterial cells do
not. 1
Muscle cells have no cell wall while some bacterial cells have a cell wall.
1
Essay (p. 2-36)
15 Similarities:
Both prokaryotic cells and eukaryotic cells are bounded by a cell membrane.
1
Both have DNA as genetic material.
1
Differences:
Prokaryotic cells have no true nucleus while eukaryotic cells have a true nucleus.
/
DNA of prokaryotic cells is lying free in the cytoplasm while DNA of eukaryotic
cells is enclosed in the nucleus. /
Prokaryotic cells are usually smaller than eukaryotic cells. /
The cell wall of prokaryotic cells does not contain cellulose while the cell wall of
eukaryotic cells contains cellulose. /
Prokaryotic cells do not have organelles bounded by a double membrane while
eukaryotic cells have organelles bounded by a double membrane. /
Prokaryotic cells do not have endoplasmic reticulum while eukaryotic cells have
endoplasmic reticulum. /
In prokaryotic cells, ribosomes are lying free in the cytoplasm while in
eukaryotic cells, some ribosomes are attached to endoplasmic reticulum and
some are lying free in the cytoplasm. (any 5)
Communication
1x5
3
Reading to learn (p. 2-37)
1
2
3
Length of Amoeba image (X to Y) = 2.6 cm
1
Length of Amoeba = 2.6/150 = 0.0173 cm = 173 μm
1
It is a eukaryote.
1
It has a true nucleus.
1
Mitochondria are the main site where energy is released.
1
Enzymes are produced from rough endoplasmic reticulum.
1