Bihar Board 12th Biology Important Questions Short Answer Type Part 2 are the best resource for students which helps in revision.
Bihar Board 12th Biology Important Questions Short Answer Type Part 2
What is biotic component of Ecosystem?
Why are the testes of human male considered extra abdominal?
The human testes lie in scrotum out side the body cavity.
Define ovulation? On which day it occur in a menstrual cycle?
Ovulation is expulsion of ovum from ovary. It takes place on 14th day of mensuration.
What is difference between spermatogenesis and Oogenesis?
Spermatogenesis – It gives rise to sperm.
Oogenesis – It is polar bodies formed which are not formed during spermatogenesis.
Name the Chemicals released by the acrosome during fertilization.
Spenrtlysin is secreated by acrosome during fertilization.
Differentiate between trophectoderm and ectoderm.
Trophoecotoderm – It is outer cellular envelop of Blasto Cyst where an ectoderm is the outermost cellular type of gastrula.
Name the hormone secreted by human placenta.
(a) Oestrogen, HCG, Human Chorionic gonadotropin.
What is Colostrum?
It is the first milk that comes from the mammary glands of the mother just after childbirth for 2 – 3 days.
Difference between Vasectomy and tubectomy.
Vasectomy – Sterilization procedure in the male in called Vasectomy.
Tubectomy – Sterilization procedure in the female is called tubectomy.
Name the devices which are used under the barrier method of contraception.
- Cervicalcap and
Name any four STD’s disease with their causal agents.
|1. Syphilis||Treponema Pattidum|
|3. Hepatitis||Hepatitis B virus (HBV)|
|4. Gonorrhoea||Neisseria gonorrhoea|
Comment upon genetic equilibrium.
Total genes and their alleles in a population (Gene pool) remain constant called genetic equilibrium.
Write main points of Lamarckism.
- Due to internal force, living things continuously increased.
- Effect of environment results new needs that produce new structure.
- Inheritance of acquired characters.
Differentiate between homology and analogy.
Homology – It is study of entier relationship of homologous structure.
Analogy – It is study of analogous structure.
Name four living fossils.
- Gingko biloba
Name Two features of Australopithecus.
It was about 1.5 meter in height. It was with bipedal locomotion, omnivorous diet and had erect posture. It had human like teeth and had erect posture.
Comment upon H.M.S. Beagle.
In 1831 Darwin got an opportunity to travel on H.M.S. Beagle ship in which Charles Darvin sailed around the world.
Differenciate between convergent and divergent evolution.
Divergent Evolution – Development of different functional structural from a common form.
Convergent Evolution – Development of similar adaptive functional structure in unrelated group of organism.
Mention two evidences of organic evolution.
The evidence of organic evolution comes from the study of homology and analogy of organs and palaeontology.
Which is responsible for sex determination in chick-sperm or ovum.
Ovum is responsible for sex determination in chick because female produces two types of gamete where one male produces same type of sperm.
What is Sickle-Cell anaemia.
Sickle Cell anaemia is an autosomal hereditary disorder in which erythrocytes become sickle shaped under oxygen deficiency.
What is bioinformatics?
It is the science concerned with development and application of computer hardware and software to the analysis.
What is repetitive DNA?
It is the DNA having multiple copies of identical sequence of nitrogen base.
Antilope is called Chiru.
Name four indigenous Cow.
- Red Sindhi and
What is neurosis?
It is a kind of mental disease of Maladaptive state.
Enumerate the symptoms of syphilis.
- Initially a red painless ulcer appears at the site of infection (eg. Penis, Vagena and Cervix).
- In late, fever, lymph node, pink skin all over the body and joint pain.
What is opsonization?
It is process of identifying pathogen by phagocyte.
What do you mean by cellular immunity?
The immunity obtained by lymphocyte is called cell immunity.
Name four Indian Common Carp.
- Rohu (Labeo rohita)
- Catla (Catla Catla)
- Mangur (Clarias batrachus)
- Calbasu (Labeo Calbasu).
Name four types of Silk.
- Mulberry Silk
- Tasar Silk
- Moonga Silk
- Arandi Silk.
What is artificial insemination?
It is the technique of transfer of siemens of male into the reproductive tract of female invitro.
What is inbreeding?
It is the process of reproduction among similar animals of a species for obtaining pure line.
What birds are use for poultry farming.
- Gees Swans
Name four carcinogens.
(A) Radiation i.e.
- U. V. rays
- Cosmic rays
(B) Tumour Viruses
(C) Mustard gas.
Differentiate between population and community.
Population – It is a group of individuals of a single species found in an area.
Community – It is a group of different species found in an area.
Enumerate any four characteristics of population.
- Birth rate
- Death rate
- Age distribution
- Population Size.
Discuss about Sarcoma?
These cancers are located in connective and muscular tissues derived from mesoderm.
Differentiate between hibernation and aestivation. Give one example of each.
(A) Hibernation – It is winter sleep in which animal passes the winter period in dormant condition.
(B) Aestivation – It is summer sleep.
Mention any two adaptation found in organisms of desert.
- Devices developed to reduce water loss so that leaves modified into Spines and Stem becomes succulent.
- C4 Photosynthesis mechanism develops.
Construct grazing food chain.
Grass → Grasshopper → Frog → Snake → Hawk.
Distinguish between primary and Secondary productivity.
Primary productivity – Rate of synthesis of organic matter by producer.
Secondary productivity – Rate of synthesis by organic matter by consumers.
Constant pyramid of number of grassland ecosystem.
Pyramid of number of grassland Ecosystem
Distinguish between primary succession and secondary succession.
Primary succession – It occurs in an area which has been bare where soil is absent.
Secondary succession – It occurs in an area which have developed recently where soil is present on substratum.
Describe two factors for loss of biodiversity.
- Habit fragmentation or loss.
- Overexploitation of biodiversity.
What is red data Book.
Red data Book in a catalogue at taxa facing risk of extinction.
Differentiate between the following:
(i) Asexual and sexual reproduction.
(ii) Binary fission and multiple fission.
(iii) Primary and secondary sex organs.
(i) Asexual and sexual reproduction:
|Asexual reproduction||Sexual reproduction|
|1. Always uniparental.||1. Generally biparental except Taenia, Fasciola.|
|2. No gametes are involved.||2. Male and female gametes are involved.|
|3. Only mitotic divisions takes place.||3. Meiosis occurs at gametogenesis. Mitosis occurs after fertilization.|
|4. Somatic cells are involved.||4. Germ cells are involved.|
|5. Offsprings are genetically identical to the parent.||5. Offsprings are genetically different from the parent.|
(ii) Binary fission and multiple fission:
(iii) Primary and secondary sex organs:
|Primary sex organs||Secondary sex organs|
|1. These form the gametes.||1. These help in conduction of gametes|
|2. They secrete sex hormones.||2. They do not secrete sex hormones.|
|3. Their growth, maintenance and functions are controlled by gonad tropins of anterior pituitary.||3. Their growth, maintenance and functions are controlled by sex hormones secreted by gonads.|