Biology questions
Multiple Choice Questions:
1. Put a tick mark against the correct alternative
in the following statements:
(a) The testes are located within the:
1. Penis
2. Scrotum
3. Ureter
4. Urinary bladder
Answer: 2. Scrotum
(b) Amoeba is most commonly reproduced by:
1. Budding
2. Regeneration
3. Binary fission
4. Multiple fission
Answer: 3. Binary fission
(c) Identify the stage which is formed after the
fertilization of the egg by the sperm?
1. Ovule
2. Foetus
3. Embryo
4. Zygote
Answer: 4. Zygote
(d) Internally, the uterus opens into:
1. Urethra
2. Vagina
3. Oviduct
4. Vulva
Answer: 2. Vagina
(e) Which one of the following represents the correct
sequence in the life history of a butterfly?
1. Egg → Larva → Adult → Pupa
2. Egg → Pupa → Adult → Larva
3. Egg → Larva → Pupa → Adult
4. Egg → Pupa → Larva → Adult
Answer: 3. Egg → Larva → Pupa → Adult
Short Answer Questions:
Question 1.
Distinguish between the following pair of terms:
(a) Egg and sperm.
(b) Sexual reproduction and asexual reproduction.
(c) Budding and Regeneration.
Solution:
(a) Egg and sperm
Egg Sperm
1. The ovaries produce eggs.
2. The egg is spherical in shape with a nucleus.
Sperm
1. The testes produce sperm.
2. Sperm has a head with the nucleus, middle piece and
tail.
(b) Sexual reproduction and asexual
reproduction.
Sexual reproduction
1. In sexual reproduction, the two sexes produce sperm
and eggs by the male and female.
2. To produce a new individual the sperm has to reach
the ovum and fuse with it. e.g.. Humans, bird, reptile,
etc.
Asexual reproduction:
1. It involves the production of an offspring from a
single parent without the fusion of reproductive cells
(gametes).
2 The process does faster multiplication, e.g. Lower
plants and animals {Amoeba).
(c) Budding and Regeneration
Budding:
Budding is a process where buds grow on the external
parent body. The buds fall off when they are large
enough.
Example: Hydra
Regeneration: Regeneration is the process that uses
cell division to regrow lost body parts.
Example: Starfish, sponges
Question 2
Define the following terms:
(a) Fertilization
(b) Implantation
(c) Puberty
Solution:
(a) Fertilization: Zygote is formed by fusing sperm
and eggs from the opposite partners. It is called
fertilization.
(b) Implantation: The fertilised egg (zygote) soon
starts developing and by the time it reaches the uterus,
a small ball of numerous cells is already formed. This is
a kind of embryo which forms a pit in the wall of the
uterus and gets fixed in it. Thus implantation occurs,
which is the natural way of fixing the embryo in the
uterus wall. This produces the state of pregnancy.
(c) Puberty: Puberty is the period during which the
reproductive systems of boys and girls mature. In girls,
it starts at the age of about ten and the first sign of
puberty is the development of breasts. In boys, it starts
at about 11 years of age of the enlargement of the
testes is its first sign. The sudden spurt in growth,
shoulder girdle grows more than a hip girdle.
Question 3.
State the reason why testes lie outside the abdomen in
a scrotum?
Solution:
The normal body temperature is too high for both the
testes to be inside the abdomen, scrotum has smooth
muscle tissues that keep the testes at a cooler
temperature than the body temperature 2°C to 3°C
lower than the body temperature which is the most
suitable temperature for sperm production.
Question 4.
Why is it important that a very large number of sperms
should be present in the semen?
Solution:
Single ejaculation of semen has 20,000,000 to
40,000,000 sperms. But only 1 or 2 sperms go into the
oviduct and fertilize the egg to form the Zygote. An
individual is formed from the embryo. It is the sperm in
the semen that is of importance, and therefore semen
quality involves both sperm quantity and quality.
Question 5.
List the structures, in their correct sequence, through
which the sperms must pass from the time they are
produced in the testes to the time they leave the
urethra.
Solution:
Sperms are produced in testes. They pass as follows:
The sperm-producing tube is in the testes. The tubes
join to form ducts leading to the epididymis which in
turn leads into a muscular sperm duct. The two sperm
ducts, one from each testis open at the top of the
urethra.
Question 6.
State the functions of the following:
(a) Ovary
(b) Testes
(c) Fallopian tubes
(d) Seminal vesicle
(e) Uterus
Solution:
(a) Ovary: Ova (eggs) and secrete female sex
hormones, oestrogen and progesterone are produced
by ovaries.
(b) Testes: A pair of testes are present in the human
male. The testes produce sperms.
(c) Fallopian tubes: There are two fallopian tubes in
the human female reproductive system.
(d) Seminal vesicle: The function of the seminal
vesicle is to store sperms and to secrete seminal fluid.
(e) Uterus: The inner lining receives, protects and
nourishes the embryo. Contractions of muscular wall
expel baby during birth.
Question 7.
Given here is a section of the female reproductive
system of human beings.
(a) Name the parts labelled 1 to 4
(b) Name the part where fertilization occurs in human
beings.
Solution:
(a)
1. Ovary
2. Fallopian tube (Oviduct)
3. Uterus (Inner lining or Muscular wall)
4. Vagina
(b) Fertilisation occurs in the upper part of the oviduct.
Sperm fuses with the egg and zygote are formed this is
called fertilisation.
Question 8.
Given alongside is a diagram of the male reproductive
system in humans. Label the parts indicated by
numbers 1 to 5, and state their functions.
Solution:
1. Seminal vesicle: A secretion which serves as a
medium for the transportation of the sperms is
produced by seminal vesicles.
2. Prostate gland: Prostate gland which pours an
alkaline secretion into the semen as it passes through
the urethra.
3. Testes: Sperms are produced in the testes.
4. Urethra: Urethra passes through the penis and
carries either urine or semen.
5. Sperm duct: The sperm pass through the sperm
ducts.
Long Answer Questions:
Practical Question.
Define the term metamorphosis. Briefly describe the
various stages occurring in the life-cycle of a butterfly.
Solution:
Metamorphosis: During normal development after the
embryonic stage, a change in the form and often habits
of an animal complete the transformation from an
immature form to an adult form in two or more distinct
stages.
The life cycle of a butterfly: The butterfly lays its
eggs on the leaves of the plants. The newborn that
comes out of the egg is called larva. It passes through
various stages of development. The larva of the
butterfly is also called Caterpillar. It is very active. It is
very voracious. It feeds and moves actively and gains
size.
It stops moving and eating and it is called a pupa. It is a
resting stage. The pupa spins thread around itself and
thus is enclosed in a covering. It is called a cocoon. This
cocoon covers the pupa and is protective in function.
During this stage, it forms the features of an adult.
After attaining adulthood the pupa comes out of the
cocoon after breaking it as an adult butterfly. The wings
of the emerged butterfly are wrinkled and soft. After an
hour
