CBSE Class 10 Biology How Do Organisms Reproduce Worksheet Set C

Explanation: The bud in the yeast appears as a protuberance.

 

 

Question : In Amoeba, binary fission takes place by the following steps:

i. The cellular constriction increases and divides the whole body into equal halves and form two daughter Amoeba

ii. A constriction appears in the cell membrane and nuclear membrane

iii. Each daughter Amoeba contains a nucleus surrounded by cytoplasm and cell membrane.

iv. Nuclear constriction increases and divides the nucleus into two daughter nuclei 

The correct sequence is :

(a) (ii), (iv), (i), (iii)

(b) (iv), (i), (ii), (iii)

(c) (iii), (iv), (i), (ii)

(d) (i), (ii), (iii), (iv)

 

 

 

Question : What is the role of the seminal vesicles and the prostate gland? 
Answer :  Secretions of seminal vesicles and prostate gland provide fluid medium to sperm to move and also provide nutrition to them. 

i. Name the system.

ii. Name the parts labelled as A-I.

iii. Describe the functions of parts C, D, E and F.

Question :  During sexual reproduction, the amount of DNA does not get doubled. Explain. 

 

Question : Explain the term 'Regeneration' as used in relation to reproduction of organism.

Answer :  Regeneration is a term which is used in relation to reproduction. Which means producing its own kind likewise regeneration is the ability of some organisms to give rise to new organisms when the individual is cut or broken up into many pieces, it is seen in multicellular organisms e.g Hydra and Planaria.

Answer :  a. A pair of ovaries- ovaries produces ova and female sex hormone. One egg is produced every month by one of the ovaries. Ova are picked up by the funnel shaped fallopian tubes.

b. Fallopian tubes- There are two fallopian tubes. It carries ova from ovary to the uterus. Fertilization occurs in fallopian tubes.

c. Uterus- Pear shaped hollow muscular organ. Fertilized ovum remains attached to the uterus wall.

d. Vagina- It is a narrow muscular tube. Its upper end is connected to the cervix of the uterus and lower end opens outside through an opening. It is a place for copulation.

If the body is cut into three, four or more pieces, each piece regenerate the missing parts. A noteworthy observation in this case is that a piece from the middle always regenerates a head towards its anterior side and tail towards its posterior side. In other words, each piece maintains its original polarity. A possible explanation of this fact is that in Planaria, the metabolic activity and hence capacity for regeneration, is the greatest at the anterior end, gradually decreases posteriorly and is minimum at the posterior end. Correspondingly, the anterior end of each piece, having greater metabolic activity, regenerative anterior part of the body and the posterior end remain as such. 

 

Answer : Double fertilization: In Angiosperms both the male gametes are functional. Double fertilization is a process in which egg nucleus and secondary nucleus are fertilized at one time by two male gametic nuclei. The fusion of one male gamete nucleus (IN) with egg or oosphere (IN) is called syngamy and results in the formation of oospore (2N).

The fusion of second make nucleus (IN) with secondary nucleus (2N) is called triple fusion which results in formation of primary endosperm nucleus (3N).

Significance.

i. Double fertilization provides stimulus to endosperm mother cell for the formation of nutritive tissue named endosperm.

ii. It ensures continued supply of nourishment to the embryo that develops from zygote.

II) The following figures illustrate binary fission in Amoeba in an incorrect Sequence:

The correct sequence is:

(a) (i),(iii),(iv),(ii) (b)(ii),(iii),(iv),(i) (c)(iv),(iii),(ii),(i) (d)(iii),(iv),(ii),(i)

Seminar: Reproductive health and sexually transmitted diseases: Children form the groups and discuss.

 

Symposium: Gender related problems: female infanticide.

 

Group discussion: If there was no sexual reproduction.

 

Debate: Is it necessary to learn about reproductive health from class VII?

 

Case Based Questions :

Read the passage carefully and answer the following questions from Reproduction is a biological process by which new individual organisms are produced. Reproduction is a fundamental feature of all life forms; each individual exists due to the process of reproduction. Reproduction is the mechanism of species continuation. Mechanism and process of reproduction varies for different species in this world.

Question. Vegetative propagation is a type of: 
(a) farming
(b) reproduction
(c) cooking
(d) movement control

Answer: B

Question. Organisms in which reproduction is a function of a specific cell type are: 
(a) multicellular organisms
(b) amoeba
(c) unicellular organisms
(d) bacteria

Answer: A

Question. Which one of the following is not a method of reproduction? 
(a) Regeneration
(b) Budding
(c) Spore formation
(d) Vegetation

Answer: D

Question. Which of the following statement is not true about reproduction? 
(a) Organisms create exact copies of themselves.
(b) Creation of a DNA copy is a basic event in reproduction.
(c) Simply breaking up into smaller pieces upon maturation is also a method of reproduction.
(d) Cell division in unicellular organisms is the method of reproduction.

Answer: A

Question. The ability of cell to divide into several cells during reproduction in plasmodium is called __________ . 
(a) budding
(b) reproductive division
(c) multiple fission
(d) binary fission

Answer: C

Read the passage carefully and answer the following questions from Asexual reproduction, in which offspring arise from a single organism, occurs in a variety of prokaryotes and eukaryotes including plants, fungi, and animals. It may have some advantages over the sexual reproduction, in which individuals of two genders, females and males, must be involved but only females can give birth to new individuals. There are several different methods of asexual reproduction. Asexual reproduction can be very rapid. This is an advantage for many organisms. It allows them to crowd out other organisms that reproduce more slowly.

Question. Hydra and Planaria can be cut into any number of pieces and each piece grows into a complete organism. This is known as: 
(a) regeneration
(b) budding
(c) fragmentation
(d) speciation

Answer: A

Question. In amoeba the splitting of the two cells during division can take place in ______ plane. 
(a) single
(b) perpendicular
(c) directional
(d) any

Answer: D

Question. Budding is a mode of asexual reproduction in: 
(a) amoeba
(b) plasmodium
(c) yeast
(d) leishmania

Answer: C

Question. The specific reproductive part in Rhizopus responsible for reproduction is: 
(a) sporadic
(b) stick
(c) hyphae
(d) sporangia

Answer: D

Question. Buds produced in the notches along the leaf margin of Bryophyllum fall on the soil and develop into new plants. This is an example of: 
(a) vegetation
(b) vegetative propagation
(c) sexual reproduction
(d) clone formation

Answer: B

Read the passage carefully and answer the following questions from Sexual reproduction is the most common method of reproduction in animals and plants. One male and one female parent are involved in the process of sexual reproduction. Sexual reproduction involves fusion of two types of reproductive cells known as gametes to form a single cell called zygote. The zygote multiplies repeatedly and undergoes specific changes to form a new individual.

Question. In plants, after fertilisation, the zygote divides several times to form an embryo within the ovule. The ovule develops a tough coat and is converted gradually into a: 
(a) bud
(b) seed
(c) fruit
(d) plant

Answer: B

Question._____ is the male reproductive part in a plant and it produces pollen grains that are yellowish in colour. 
(a) Stamen
(b) Pistil
(c) Carpel
(d) Petal

Answer: A

Question. What is the source of variations in populations of organisms? 
(a) DNA copying is error free
(b) DNA copying is not error free
(c) Protein formation
(d) Involvement of only one parent

Answer: B

Question. The reproductive parts of angiospermsarelocated in the: 
(a) fruit
(b) pistil
(c) flower
(d) stigma

Answer: C

Question. As the rate of general body growth begins to slow down, reproductive tissues begin to mature. This period during adolescence is known as: 
(a) puberty
(b) adulthood
(c) germination
(d) reproduction

Answer: B

Read the passage carefully and answer the following questions from Sexual reproduction is a method to give rise to one’s progeny. In higher animals, male and female gametes are produced by different individuals to carry out sexual reproduction. Such individuals are said to be unisexual. However, in some animals like flatworm, earthworm, leech, and hydra both male and female gametes are produced by the same individual. Such organisms are said to be hermaphrodites or bisexual. Male and female gametes fertilise to form a zygote that has trail of characters from both the parents.

Question. Why are pollens spiny? 
(a) Help in Fertilisation
(b) For easy pollination
(c) To attach to bodies of insects
(d) Appearance

Answer: C

Question. What is the principle of natural contraceptive methods? 
(a) Avoiding sperm and ovum to meet
(b) Avoiding release of egg
(c) Avoiding release of sperm
(d) Abortion when pregnant

Answer: A

Question. Where does fertilisation occur in human females? 
(a) Cervix
(b) Vagina
(c) Uterus
(d) Oviduct

Answer: D

Question. The offspring formed by sexual reproduction exhibit more variations because _________. 
(a) sexual reproduction is a lengthy process
(b) genetic material comes from two parents of different species
(c) genetic material comes from two parents of same species
(d) genetic material comes only from one parent

Answer: C

Question. The number of chromosomes present in parents and offspring of a particular species remains constant due to ________. 
(a) doubling of chromosomes during zygote formation
(b) halving of chromosomes during gamete formation
(c) doubling of chromosomes after gamete formation
(d) halving of chromosomes after gamete formation

Answer: B

The below given picture shows a few methods of contraception and avoiding sexually transmitted diseases in humans. See the picture carefully and answer the following questions from 

Question. Use of condom for contraception is a: 
(a) mechanical method
(b) surgical method
(c) hormonal method
(d) chemical method

Answer: A

Question. The best way to avoid sexually transmitted diseases is by use of: 
(a) a condom
(b) medicine
(b) chemical
(d) IV injection

Answer: A

Question. Which one of the following statements is not true? 
(a) Prenatal sex determination has been prohibited by law in India.
(b) Illegal sex-selective abortion of female foetus in India is the prime reason for unbalanced male to female sex ratio.
(c) Contraceptive pills change hormonal balance in a female body.
(d) Mechanical barriers for contraception is available only for males.

Answer: D

Question. Which one out of the below given terms is STD? 
(a) Kala azar
(b) Jaundice
(c) Pyorrhea
(d) Syphilis

Answer: D

Question. IUCD is used for: 
(a) Vegetative propagation
(b) Prevent miscarriage
(c) Contraception
(d) In vitro fertilisation

Answer: C