CBSE Class 12 Biology Reproduction in Organisms VBQs

Question. Lifespan of tortoise is
(a) 100-150 years
(b) 250 years
(c) 20 years
(d) 1 year
Answer.A

Question. Single-celled animals are said to be immortal because
(a) they grow indefinitely in size
(b) they can tolerate any degree of change in temperature
(c) they can reproduce throughout their lifespan
(d) they continue to live as their daughter cells
Answer.D

Question. Arrange the organisms shown below in the increasing order of their lifespans.

(a) Parrot < Crow < Crocodile
(b) Crow < Crocodile < Parrot
(c) Crocodile < Parrot < Crow
(d) Parrot < Crocodile < Crow
Answer.B

Question. Reproduction can be considered as
(a) a biological process
(b) a cycle of birth, growth and death
(c) a process that enables continuity of species
(d) All of the above
Answer.D

Question. Study the given figures and processes representing the binary fission in Amoeba.

A. Daughter cells formation
B. Enlargement of nucleus
C. Parent cell
D. Constricted cell formation
E. Minimisation of pseudopodia
Arrange the figures and processes in the correct sequence and select the correct answer.
(a) D→ C→ A→ B→ E
(b) C→ D→ A→ B→ E
(c) C→ E→ B→ D→ A
(d) D→ C→ B→ E→ A
Answer.C

Question. Asexual reproduction is a method of reproduction in which participation of ……… takes place.
(a) one individual
(b) two individuals (same species)
(c) multi-individuals
(d) two individuals (different species)
Answer.A

Question. Clones are
(a) morphologically similar individuals
(b) genetically similar individuals
(c) Both (a) and (b)
(d) None of the above
Answer.C

Question. ....... is the fastest method to obtain clones.
(a) Induced mutation
(b) Parasexual hybridisation
(c) Vegetative reproduction
(d) Parthenogenesis
Answer.C

Question. Asexual reproduction is common in
(a) single-celled organisms
(b) plants with relatively simple organisation
(c) animals with relatively simple organisation
(d) All of the above
Answer.D

Question. Cell division is the mode of reproduction in
(a) monerans
(b) protists
(c) Both (a) and (b)
(d) None of the above
Answer.C

Question. Reproduction in Amoeba is carried out through
(a) gemmule formation
(b) binary fission
(c) budding
(d) plasmotomy
Answer.B

Question. In Amoeba, under unfavourable conditions, …A… takes place but under favourable conditions …B… occurs.
Identify A and B.
               A                      B
(a) Sporulation             Encystation
(b) Encystation             Sporulation
(c) Binary fission           Encystation
(d) Multiple fission         Encystation
Answer.B

Question. Zoospores are
(a) motile gametes of Chlamydomonas
(b) non-motile gametes of sponges
(c) motile gametes of Hydra
(d) non-motile gametes of Penicillium
Answer.A

Question. Asexual reproductive structures found in Penicillium are
(a) conidia
(b) buds
(c) gemmules
(d) zoospore
Answer.A

Question. Gemmule formation is a common mode of reproduction in
(a) Hydra
(b) sponge
(c) Penicillium
(d) Amoeba
Answer.B

Question. Hydra reproduces by
(a) Budding
(b) Fragmentation
(c) Gemmule formation
(d) Both (a) and (b)
Answer.D

Question. Study the following diagram and the information
given below.

A. Zoospore of Chlamydomonas.
B. Conidia of Penicillium.
C. Buds in Hydra.
D. Gemmulesin sponge.
All the above are
(a) bodies involved in sexual reproduction
(b) bodies involved in asexual reproduction
(c) bodies of young ones
(d) All the above are correct
Answer.B

Question. Refer the given figures which show three different types of fission.

A. Longitudinal fission
B. Transverse fission
C. Multiple fission
Select the option which correctly matches them with the organism in which they occur.
       A                      B                   C
(a) Euglena          Plasmodium    Amoeba
(b) Plasmodium    Paramecium    Euglena
(c) Euglena          Paramecium    Escherichia
(d) Euglena          Paramecium    Amoeba
Answer.D

Question. Which one of the following pairs is not correctly match?

Answer.C

Question. Offsets are produced by NEET 2018
(a) parthenocarpy
(b) mitotic divisions
(c) meiotic divisions
(d) parthenogenesis
Answer.B

Question. Refer to the given figures and identify X and Y in these.

(a) X–Buds, Y–Nodes
(b) X–Nodes, Y–Adventitious buds
(c) X–Nodes, Y–Adventitious roots
(d) X–Eyes, Y–Nodes
Answer.B

Question. Which one of the following is correctly matched?
(a) Onion – Bulb
(b) Ginger – Sucker
(c) Chlamydomonas – Conidia
(d) Yeast – Zoospores
Answer.A

Question. Choose the option with correct identification of A, B,C, D and E given below.

Answer.D

Question. Which of the following is not a vegetative propagule?
(a) Offset
(b) Antherozoid
(c) Rhizome
(d) Bulbil
Answer.B

Question. If a leaf cell of Agave have X chromosome, then what will be the number of chromosomes in a cell of its bulbil?
(a) 2X
(b) X
(c) X/4
(d) X/2
Answer.B

Question. Identify the plant which contains the features given below.
I. The plant was introduced in India because of its beautiful flowers and shape of leaves.
II. It can propagate vegetatively at a phenomenal rate and spread all over water body in a short period.
III. It is very difficult to get rid of these plants.

Answer.B

Question. The site of origin of the new plantlets in potato,Dahlia, ginger and banana is
(a) floral buds present on stem
(b) internodes of modified stem
(c) nodes of modified stem
(d) adventitious buds present on root
Answer.C

Question. Which one of the following options shows two plants in which new plantlets arise from the same organ?
(a) Guava and ginger
(b) Potato and sweet potato
(c) Dahlia and mint
(d) Potato and sugarcane
Answer.D

Question. Some organisms are capable of asexual or sexual reproduction. Under favourable conditions, reproduction proceeds asexually. When conditions become more stressful reproduction switches to a sexual mode. Why?
(a) Sexual reproduction is simple and more rapid allowing larger numbers of offspring to be produced
(b) Sexual reproduction requires two separate individuals, who can mutually provide nutrient support during stress
(c) Sexual reproduction produces individuals with new combinations of recombined chromosomes increasing diversity
(d) Asexual reproduction requires more energy
Answer.C

Question. A scion is grafted to a stock. The quality of fruits produced will be determined by the genotype of
(a) stock
(b) scion
(c) Both (a) and (b)
(d) Neither (a) nor (b)
Answer.B

Sexual Reproduction

Question. Which one of the following generates new genetic combinations leading to variation? NEET 2016, 13
(a) Vegetative reproduction
(b) Parthenogenesis
(c) Sexual reproduction
(d) Nucellar polyembryony
Answer.C

Question. Sexual reproduction involves formation of male and female gametes by
(a) same individual
(b) different individual of opposite sex
(c) Both (a) and (b)
(d) All of the above
Answer.C

Question. The growth phase of an organism before attaining sexual maturity is referred to as
(a) juvenile phase
(b) pre-reproductive phase
(c) Both (a) and (b)
(d) None of these
Answer.C

Question. Select the correct sequence from the following.
I. Juvenile phase → Senescent phase→ Reproductive phase
II. Juvenile phase→ Reproductive phase→ Senescent phase
III. Reproductive phase→ Juvenile phase→ Senescent phase
IV. Pre-reproductive phase→ Reproductive phase→ Senescent phase
(a) I and II
(b) I and IV
(c) III and IV
(d) II and IV
Answer.D

Question. Which one of the following flowers only once in its lifetime? NEET 2018
(a) Mango
(b) Jackfruit
(c) Bamboo species
(d) Papaya
Answer.C

Question. Strobilanthes kunthiana is also called
(a) Neelakurinji
(b) Peela kuranji
(c) Hara kuranji
(d) Kala kuranji
Answer.A

Question. Oestrus cycle is cyclic change in the activities of ovaries and accessory duct in non-primates during
(a) reproductive (seasonal) period
(b) maturation period
(c) ageing period
(d) juvenile period
Answer.A

Question. Organisms reproducing throughout the year are called…… breeders, e.g. … and those who show recurring sexual activity are called …… breeders, e.g. … .
(a) continuous, sparrow, seasonal, hen
(b) seasonal, lizard, continuous, hen
(c) continuous, man, seasonal, tiger
(d) seasonal, hen, continuous, tiger
Answer.C

Question. Select the correct sequence of events.
(a) Gametogenesis→ Gamete transfer→ Syngamy→ Zygote→ Cell division (Cleavage)→ Cell differentiation→ Organogenesis
(b) Gametogenesis→ Gamete transfer→ Syngamy→ Zygote→ Cell divison (Cleavage)→ Organogenesis→ Cell differentiation
(c) Gametogenesis→ Syngamy→ Gamete transfer→ Zygote→ Cell division (Cleavage)→ Cell differentiation→ Organogenesis
(d) Gametogenesis→ Gamete transfer→ Syngamy→ Zygote→ Cell differentiation→ Cell division (Cleavage)→ Organogenesis
Answer.A

UNIT VI- REPRODUCTION

• Your younger sister has seen a banana tree in backyard of a house. She could see the fruits but no seeds. She wants to know how a new plant of banana will be produced without seed. What will you explain to your sister?

• A popular TV program shows in some village, girls are killed soon after their birth. Do you approve such practice? What impact does it have on population?

• Sunita’s bhabhi is not allowed to enter the kitchen during the days of her menstrual cycle. Sunita’s mother thinks that she is impure and dirty and the food prepared by her is also unhygienic. Give your opinion about such traditional belief.

• Monika is a sex worker. You are a NGO worker. You are given the responsibility to educate the sex worker about sexually transmitted diseases. Specify any two ways of prevention from such diseases.

• Neeru and Narim have a three year old daughter. During her second pregnancy she wants to go for sex determination test and if needed medical termination of pregnancy. Do you think her decision is right? Justify your answer.

• Nidhi is a class VI student visits a field and finds that all the flowers of some plant are ‘closed’. She thinks such flowers will not open and due to no pollination seeds will not be formed. Such plants will be ‘propagated’ vegetative. Do you agree with Nidhi’s findings? Explain.

• Pooja’s grandmother blames her mother for giving birth to three daughters and wants another marriage of her son. Is it right to blame a female for sex determination? Justify your answer.

• Maya saw a farmer spraying some chemical on flowers, on asking she came to know that this act will lead to the formation of fruits without fertilization. Maya thinks that fruits such developed are not good to eat as chemicals are sprayed on it. Explain the difference between such spray and usual pesticide spray.

• Rahul and his friends are having discussion about a recently released movie in which hero is a sperm donor. His friends say that sperm donation is a means to earn money. Rahul explains that sperm donation can help infertile couples. Whom do you think is right? In which type of infertile cases such sperm donation is helpful. Draw a neat and labeled diagram of a sperm.

UNIT-6 Reproduction

Answers & Values

1. In banana the vegetative propagation is with the help of rhizome
Values
• Awareness
• Observation

2. No, I do not approve such practice as girls are equally important in the society. Otherwise the sex ratio will decrease.
Values
• Sensitivity to words others
• Awareness

3. Menstrual cycle is a normal process in the body of female which helps in reproduction.
Values
• Self-awareness about body.
• Compassion for others.

4. a) Always use condom during coitus
b) in case of doubt of any disease consult doctor
Values
• Services to society
• Compassion
• Awareness of STD

5. No Sex determination and MTP is not legal
Values
• Should be ethical
• Awareness

6. No the flowers which do not open can have self-pollination and produce seed. They can be propagated through seed.
Values
• Concern about plants
• Observation
• Critical thinking

7. No. Female produces all eggs with X chromosomes while male is heterogametic and produce two types of gametes X and Y. It is the fusion of his gamete (X or Y) with egg of X type which determine the sex of baby
Values
• Understanding.
• Respect for female.

8. The chemical sprayed by farmer is growth hormone which will induce parthenocarpy. This is not causing any harm to fruit or to the health of consumer. Pesticides are harmful to human health.
Values
• Sensitivity and awareness about use of chemicals.
• observation

9. a) Rahul is right . As it helps infertile couples. It is helpful in following cases
I) Inability of male partner to inseminate.
II) Very low sperm count.
Values
• Courage
• Believing that “other” can make a world of difference
• Compassion for others

REPRODUCTION IN ORGANISMS

Value Based Questions

Q.1. A researcher attempts making apomicts of hybrid seeds.
a. What are the advantages of this attempt?
b. How does it occur naturally in mango?
c. How do you think this experiment will help the farmer?
Ans. Apomicts of hybrid seeds. 
a. No segregation of desirable characters
b. Explanation of apomixes in mango 
c. Cheap and can therefore save money and energy

Q.2. The application for admission of a school student was rejected because the mother was HIV positive. Justify the ecision of the school giving relevant reasons.
Ans. The school should be sensitive and empathetic and is not justified in denying admission since AIDS is transmitted in specific ways (1). The four methods 

Q.3. Mrs and Mr Gupta want to know the sex of their unborn child. He doctor refused to comply to this request. a. Justify the doctor’s decision. b. Explain sex determination in man. 
Ans. The doctor is ethical and right since it is illegal to tell the couple the sex of the child. (1) Sex determination in man. 

Q.4. A lady died due to complication in pregnancy in a hospital where MTP was not legalized. a. Do you think the decision of the hospital was correct? b. What are the situations where MTP can be advised?
Ans. It is not correct to deny medical help by the hospital. The lady should have been treated and her life could have been saved if timely intervention was given. (1) Two situation where MTP is advised-

Q.5. According to a survey, at least 10% of Indian couples suffer from infertility and we have so many orphaned and destitute children, who would probably not survive till maturity, unless taken care of. A counselor advised an infertile couple to adopt a child.
a. Why did the counselor give such an advice?
b. List any two methods to treat infertility.
Ans. Counsellor is sensitive and empathetic. He has concern for the orphaned children. (1) any two methods to treat infertility. 

Q.6. Some young mothers hesitate to breast their children. Is it biologically and ethically correct on their part? What is the significance of mother’s milk?
Ans. No, it is not correct to deny infant of mother’s milk (1). Significance of mother’s milk

Q.7. Due to increased health facilities and better living conditions human population is growing at an exponential rate.
a. Is it morally correct for one species to grow at this rate? Justify your answer.
b. Describe one natural method and one irreversible le method of contraception.
Ans. Due to increased health facilities and better living conditions human population is growing at an exponential rate.
a. No, it is not correct. Man is only part of the environment and cannot rule over the other species.
b. One natural method and one irreversible method of contraception. 

Q.8. People suffering from hepatitis B of HIV are advised to use a contraceptive method to prevent STD.
a. Name the method.
b. List the symptoms of STD
c. What is the human value from using this method?
Ans. A) condoms (1) b) Symptoms (2). c) To not spread the disease/ concern for health of others

Q.9. What is the special feature of sporopollenin in an pollen grain? What life skill can you learn from this?
Ans. special feature of sporopollenin in an pollen grain (1) life skill – tolerance and ability to overcome all kinds of adversities in life

Q.10. How do flowers reward their insect pollinators? Explain. What value does this relationship illustrate? 
Ans. Floral rewards (1) Value- sharing/ give and take / mutual understanding / good relationship (1)

More Questions

Q.1 Your younger sister has seen a banana tree in backyard of a house. She could see the fruits but no seeds. She wants to know how a new plant of banana will be produced without seed. What will you explain to your sister?
Ans.In banana the vegetative propagation is with the help of rhizome
Values
• Awareness 
• Observation

Q.2 A popular TV programme shows in some village, girls are killed soon after their birth. Do you approve such practice? What impact does it have on population?
2. No, I do not approve such practice as girls are equally important in the society. Otherwise the sex ratio will decrease.
Values
• Sensitivity to words others
• Awareness

3Q. Sunita’s bhabhi is not allowed to enter the kitchen during the days of her menstrual cycle. Sunita’s mother thinks that she is impure and dirty and the food prepared by her is also unhygienic. Give your opinion about such traditional belief.
3. Menstrual cycle is a normal process in the body of female which helps in reproduction.

Values
• Self awareness about body.
• Compassion for others.

Q.4 Monika is a sex worker. You are a NGO worker. You are given the responsibility to educate the sex worker about sexually transmitted diseases. Specify any two ways of prevention from such diseases.
4. a) Always use condom during coitus
b) in case of doubt of any disease consult doctor
Values
• Services to society
• Compassion
• Awareness of STD

Q.5 Neeru and Narim have a three year old daughter. During her second pregnancy she wants to go for sex determination test and if needed medical termination of pregnancy. Do you think her decision is right? Justify your answer.
5. No
Sex determination and MTP is not legal
Values
• Should be ethical
• Awareness

Q.6 Nidhi is a class VI student visits a field and finds that all the flowers of some plant are ‘closed’. She thinks such flowers will not open and due to no pollination seeds will not be formed. Such plants will be ‘propagated’ vegetative. Do you agree with Nidhi’s findings? Explain.
6. No the flowers which do not open can have self pollination and produce seed. They can be propagated through seed.
Values
• Concern about plants
• Observation
• Critical thinking

Q.7 Pooja’s grandmother blames her mother for giving birth to three daughters and wants another marriage of her son. Is it right to blame a female for sex determination? Justify your answer.
7. No. Female produces all eggs with X chromosomes while male is heterogametic and produce two types of gametes X and Y. It is the fusion of his gamete (X or Y) with egg of X type which determine the sex of baby
Values
• Understanding.
• Respect for female.

Q.8 Maya saw a farmer spraying some chemical on flowers, on asking she came to know that this act will lead to the formation of fruits without fertilization. Maya thinks that fruits such developed are not good to eat as chemicals are sprayed on it. Explain the difference between such spray and usual pesticide spray.
8. The chemical sprayed by farmer is growth hormone which will induce parthenocarpy. This is not causing any harm to fruit or to the health of consumer. Pesticides are harmful to human health.
Values
• Sensitivity and awareness about use of chemicals.
• observation

Q.9Rahul and his friends are having discussion about a recently released movie in which hero is a sperm donor. His friends say that sperm donation is a means to earn money. Rahul explains that sperm donation can help infertile couples. Whom do you think is right? In which type of infertile cases such sperm donation is helpful. Draw a neat and labeled diagram of a sperm.
9. a) Rahul is right . As it helps infertile couples. It is helpful in following cases
I) Inability of male partner to inseminate.
II) Very low sperm count.
Values
• Courage
• Believing that “other” can make a world of difference
• Compassion for others