The branch of Biology that deals with the principles of classification of organisms is known as
คำตอบ
(C)
taxonomy
2
Which of the following structures is a tissue
คำตอบ
(B)
Blood
3
Which of the following cells are not regarded as specialized?
คำตอบ
(D)
somatic cells
4
Which of the following pairs of cells carry out the same function?
คำตอบ
(B)
Spermatozoan and ovum
5
If Amoeba is placed in a salt solution. the contractile vacuoles would
คำตอบ
(C)
be formed less frequently
6
In which of the following habitats is Paramecium no found
คำตอบ
(B)
Aquarium
7
The following processes are involved in water movement in the endodermis except
คำตอบ
(D)
active transport
8
Cells that utilise a lot of energy are characterized by the presence of a large number of
คำตอบ
(B)
mitochondria
9
The part labelled II in the diagram is
คำตอบ
(C)
chromatid
10
The part labelled I is called the
คำตอบ
(D)
spindle
11
Secondary growth is brought about by the activities of the
คำตอบ
(D)
vascular cambium and phellogen
12
A monocot root IS different from a dicot root by having
คำตอบ
(C)
wide pith
13
Which of the following statements best describes haemoglobin? It is
คำตอบ
(C)
an oxygen carrying pigment
14
Inhaled air is made warm and moist in the
คำตอบ
(B)
nasal cavity
15
Which of the following structures is not involve in respiration?
คำตอบ
(C)
Stomach
16
Filtrate in the Bowman’s capsule contains vitamins because
คำตอบ
(C)
they have low molecular weight
17
ore sweat is produced during muscular exercise because
คำตอบ
(C)
the temperature of the body rises
18
Which of the following neurons may not have myelin sheath?
คำตอบ
(B)
Intermediate neurons
19
Which of the following is not an effector organ?
คำตอบ
(C)
Nose bridge
20
During sexual reproduction in Paramecium, how many times does the zygote divide to produce eight nuclei?
คำตอบ
(C)
3
21
The testes in male mammals descend into the scrotal sac because
คำตอบ
(D)
they require a relatively low temperature
22
Some animals return to water bodies to reproduce because
คำตอบ
(D)
the temperature on land is not suitable for the development of their embryos
23
Which of the following methods is appropriate for the cultivation of cassava?
คำตอบ
(D)
Stem cutting
24
What will be the chromosome number of the hybrid of two varieties of a plant with 36 chromosomes in the endosperm cell?
คำตอบ
(C)
35
25
Kreb’s cycle occurs in the
คำตอบ
(A)
mitochondria
26
The process whereby electrons are emitted from chlorophyll and returned to it unchanged is known as?
คำตอบ
(D)
cyclic photophorylatlion
27
Which of the following statements about photosynthesis is not true?
คำตอบ
(A)
Plants can photosynthesize without an increase in dry weight
28
The removal of all the phloem tissues of the stem of a plant close to the root system for a long period of time is likely to
คำตอบ
(D)
cause the p ant to wither and die
29
Which of the following groups of substances are not six-carbon compounds?
คำตอบ
(D)
Pyruvate and cellulose
30
The conversion of glucose to starch in the leaf during the day principally
คำตอบ
(C)
enables the leaf to store the starch
31
A purple colour was obtained when sodium hydroxide solution and a drop of copper sulphate solution were added to a food substance. The food substance is likely to be a
คำตอบ
(C)
protein
32
Which of the following enzymes is active in the duodenum?
คำตอบ
(C)
Trypsin
33
The following organisms are producers except
คำตอบ
(B)
Mushroom
34
Which of the following structures produces the greatest variety of digestive enzymes?
คำตอบ
(B)
Pancreas
35
The following are abiotic components of an ecosystem except
คำตอบ
(C)
bacteria
36
Use the information on capture-recapture method to calculate the total number of organisms in a habitat.
First capture = 200
Second capture = 120
Number of organisms with mark in second capture = 40
The total number of organisms therefore is
คำตอบ
(C)
600
37
Ecological investigation in a habitat includes the following procedures except
คำตอบ
(C)
determining the genetic makeup of specimens
38
Which of the following substances when lost from the body of a mammal will not be returned to the ecosystem?
คำตอบ
(C)
Heat energy
39
The rate of decomposition of organisms is faster in the tropical rain forest than in other biomes because
คำตอบ
(C)
of abundance of water
40
A xerophyte conserves water by possession of the following features except
คำตอบ
(C)
broad leaves
41
The falling off of leaves of deciduous trees is helpful to the plant because it
คำตอบ
(A)
reduces the rate of transpiration
42
A sample of wet garden soil of known weigh was heated to constant weight. The loss of weight is due to loss of
คำตอบ
(C)
water and organic matter
43
Assuming that a period of stable population size is followed by a period when natality increases by ten (1O) per cent and immigration increases by twenty (20) percent of population size. The population size will
คำตอบ
(C)
begin to increase
44
Which of the following methods does not make water fit for drinking?
คำตอบ
(C)
Distillation
45
Vaccination results in
คำตอบ
(B)
production of antibodies which destroy toxins of germs
46
Leguminous crops are incorporated into crop rotation in order to
คำตอบ
(B)
promote nitrogen fixation
47
Which of the following practices improves crop yield in a clayey soil? Addition of
คำตอบ
(B)
lime and humus
48
Which of the following activities promotes forest conservation?
คำตอบ
(C)
Afforestation
49
Which of the following statements is not true about continuous variation? It
คำตอบ
(D)
is usually controlled by one or two pair(s) of genes
50
Acquired characters are
คำตอบ
(C)
caused by the environment
51
Differences in characteristics observed between individuals of the same species is known as
คำตอบ
(D)
variation
52
Which of the following statements best describes protein synthesis?
คำตอบ
(A)
DNA is directly involved in translation
53
If a person has two alleles of the sickle cell anaemia gene, the person
คำตอบ
(C)
has the disease
54
What is the probability? of a man of blood group AB married to a woman of blood group O producing a child of blood group O?
คำตอบ
(A)
0%
55
A man with blood group It IA IA is married to a woman with blood group IA IO. The blood group of their son is likely to be
