Class 12th Biology 2013 Set1 Delhi Board Paper Solution
Differentiate between inbreeding and outbreeding in cattle. State one advantage and one disadvantage for each one of them.
| SN | Inbreeding | Outbreeding | |
| 1 | Mating of more closely related individuals | Mating of unrelated animals | |
| 2 | Mating is between animals of same breed for 4-6 generations | If mating is b etween animals of sam e breed them there should be no common ancestor for 4-6 generations. | |
| 3 | Mating is between same species. |
|
Advantage of inbreeding
It increases homozygosity so is used for developing pure lines.
Disadvantage of inbreeding
It causes inbreeding depression, due to that decline in survival and reproduction occur.
Advantage of out breeding
It produces hybrids with desirable characters like better lactation period and high milk productions.
Disadvantage of inbreeding
It causes outbreeding depression, that is decline in reproductive fitness,purelines are aslo created in outbreeding.
Popular Questions of Class 12th biology
- Q:- What is spermatogenesis? Briefly describe the process of spermatogenesis.
- Q:- Why is reproduction essential for organisms? Answer
- Q:- Write a short note on
(a) Adaptations of desert plants and animals
(b) Adaptations of plants to water scarcity
(c) Behavioural adaptations in animals
(d) Importance of light to plants
(e) Effect of temperature or water scarcity and the adaptations of animals. - Q:- With a neat diagram explain the 7-celled, 8-nucleate nature of the female gametophyte.
- Q:- What is DNA fingerprinting? Mention its application.
- Q:- Describe the structure of a seminiferous tubule.
- Q:- What is oogenesis? Give a brief account of oogenesis.
- Q:- What is triple fusion? Where and how does it take place? Name the nuclei involved in triple fusion.
- Q:- With a neat, labelled diagram, describe the parts of a typical angiosperm ovule.
- Q:- Explain the Law of Dominance using a monohybrid cross.
Recently Viewed Questions of Class 12th biology
- Q:- Why is that once a person starts taking alcohol or drugs, it is difficult to get rid of this habit? Discuss it with your teacher.
- Q:- Differentiate between gametogenesis from embryogenesis.
- Q:- In the medium where E. coli was growing, lactose was added, which induced the lac operon. Then, why does lac operon shut down some time after addition of lactose in the medium?
- Q:- Draw a labeled diagram of a Graafian Follicle?
- Q:- What is primary productivity? Give brief description of factors that affect primary productivity.
- Q:- In which food would you find lactic acid bacteria? Mention some of their useful applications.
- Q:- If the sequence of one strand of DNA is written as follows:
5-ATGCATGCATGCATGCATGCATGCATGC-3
Write down the sequence of complementary strand in 5→3 direction - Q:- If the sequence of the coding strand in a transcription unit is written as follows:
5-ATGCATGCATGCATGCATGCATGCATGC-3
Write down the sequence of mRNA. - Q:-
Fill in the blanks:
(a) Humans reproduce __________. (asexually/sexually)
(b) Humans are__________. (oviparous/viviparous/ovoviviparous)
(c) Fertilization is __________ in humans. (external/internal)
(d) Male and female gametes are __________. (diploid/haploid)
(e) Zygote is __________. (diploid/haploid)
(f) The process of release of the ovum from a mature follicle is called__________.
(g) Ovulation is induced by a hormone called the __________.
(h) The fusion of male and female gametes is called _____________.
(i) Fertilisation takes place in _____________.
(j) Zygote divides to form _____________which is implanted in uterus.
(k) The structure which provides vascular connection between fetus and uterus is called ____________. - Q:- What is the mechanism by which the AIDS virus causes deficiency of immune system of the infected person?