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Question: 1
Name the hormones secreted by placenta.
Answer: 1
1-68Placental lactogen and progestron is secreted by the placenta.
Question: 2
Define placenta. Give its function.
Answer: 2
2-68Placenta acts as bridge between mother body and foetus. Once the placenta established it start secreting progesterone hormone which maintain pregnancy. Placenta also play role in transport of nutrients and oxygen to foetus and bring back waste from the foetus to mother body.
Question: 3
What is vernalization?
Answer: 3
3-68Biennials and perennials plants are stimulated to flower by exposure to low temperature. This is called vernalization. Duration of low temperature (chilling) treatment required varies from four days to three months.Temperature around 4oC is found to be very effective.
Question: 4
Write about the Gonorrhoea disease.
Answer: 4
4-68it is caused by gram positive bacteria Neisseria gonorrhoeae mainly affecting the mucous membrane of urinogenital tract. New borne infants may acquire serious eye infection if they pass through the infected birth canal. It is highly contagious through the sexual contact.
Question: 5
Why seed plants are predominantly present all around as?
Answer: 5
5-68Seed plants are very common around us become these plants are have many adaptations to survive on land like protected seeds,flower and fruit formation.Seed dispersal plays an important role in distribution of flowering plants.
Question: 6
What are test tube babies?
Answer: 6
6-68Parental sperms and ovum is fertilized in vitro,(outside the female body) and then zygote is implanted back into mother uterus, placenta established and remaining development takes place in the body of the mother leading to normal birth.
Question: 7
What is diplohaplontic life cycle? Give its types.
Answer: 7
7-68In sexual reproduction,plants have diplohaplontic life cycle with alternating diploid sporophyte and haploid gametophyte generations. its type are isomorphic generations and heteromorphic generations.
Question: 8
What is genital herpes?
Answer: 8
8-68It is caused by herpes simplex type 2 virus, most frequently transmitted by sexual contact causing infection of the genitalia. It produces genital sorness and ulcers in the infected areas. In infected pregnant women,virus can transmitted to infant during birth,causing damage to eyes and CNS of the infant.
Question: 9
Define seed dormancy. Write its signifance. Give Its importance.
Answer: 9
9-68it is special condition of rest, which enables an embryo to survive the unfavorable environmental conditions.
Question: 10
What is menopause? Which factors affect reproductive cycle in female?
Answer: 10
10-68The end or complete stop of the menstrual cycle is called menopause,after which the female stops producing the ova. Malnourishment and emotional stresses effect the female reproductive cycle which may be disturbed. The cycle is not completed in its normal 28 days.
Question: 11
Apomixes is a form of parthenogenesis.Discuss
Answer: 11
11-68In apomixes a diploid cell either from the nucellus or megaspore develops into a functional embryo in the absence of a male gamete. The rest of the ovule develops into seed and and ovary into fruit.
Question: 12
Define gonorrhea and AIDS.
Answer: 12
12-68Gonorrhea is caused by gram positive bacteria called Neisseria gonorrhoeae,mainly affecting the mucous membrane of urinogenital tract. New born infants may acquire serious eye infection if they pass through infected birth canal. It is highly contagious through sexual contact.
Question: 13
What is seed dormancy?
Answer: 13
13-68It is special condition of rest, which enables an embryo to survive the long period of unfavorable environmental conditions such as water shortage or low temperature.
Question: 14
Define parthenocarpy with example.
Answer: 14
14-68Formation of fruit without fertilization is called parthenocarpy. For example seedless grapes and banana.
Question: 15
Write about the disease syphilis? Or Give causes and symptoms of syphilis?
Answer: 15
15-68It is caused by a spirochete, Treponema pallidum. It damages the reproductive organs,eyes,bones,joints,CNS,heart and skin. Sexual contact is major source of its spread.
Question: 16
Define phytochromes and give its types.
Answer: 16
16-68Phytochromes are blue light sensitive proteins which receives the stimulus for flowering. They are of two type i.e, P660or red phytochrome and P730 or far red phytochrome.
Question: 17
For which the abbreviation of STD is used?
Answer: 17
17-68This abbreviation stands for sexually transmitted diseases.
Question: 18
Define vernalization.
Answer: 18
18-68Chilling treatment give to the plant seeds before sowing is called vernalization.
Question: 19
Name two sexually transmitted disease and their control.
Answer: 19
19-68Genital herpes and AIDS. These sexually transmitted diseases can be controlled by avoiding sexual contact with affected person and adopting the hygienic conditions and also by taking medical treatment.
Question: 20
Define haploid parthenogenesis.
Answer: 20
20-68In the honey bees male develops without fertilization of egg. The queen bee carrying male gametes from the male has the ability to lay eggs that have not been fertilized.If these eggs are not fertilized then they develops in to haploid offspring. It is called haploid parthenogenesis.
Question: 21
Differentiate the internal and external fertilization.
Answer: 21
21-68External Fertilization:Fertilization which occurs outside the body is know as external fertilization.
It occurs aquatic environment where male gametes can swin towards females gametes in water medium.
It occurs aquatic environment where male gametes can swin towards females gametes in water medium.
Question: 22
Define parthenocarpy. How it is artificially induced?
Answer: 22
22-68Formation of fruit without fertilization is called parthenocarpy. It is artificially can be induced by applying synthetic auxin(NAA).
Question: 23
What is diploid parthenogenesis?
Answer: 23
23-68In diploid partenogenesis a diploid egg is formed due to non disjunction of chromosomes, they retain their diploid number of chromosomes; diploid egg then develops in to young female.
Question: 24
How Implantation differes from gestation?
Answer: 24
24-68Implantation: Implantation is when the new human created at fertilization implants in the uterus. The newly created offspring,technically referred to as a blastocyst,travels to the uterus through the fallopian tube and implants in the wall of the uterus.
Question: 25
Define fruit set.
Answer: 25
25-68Retention of the ovary which become fruit after the fertilization. Or it is the process in which ovary after fertilization start to develop in to fruit is called fruit set.
Question: 26
What is Gonorrhoa and who caused it?
Answer: 26
26-68It is caused by a gram positive bacterium Neisseria gonorrhoeae,mainly affecting the mucous membrane of urinogenital tract. New born infants may acquire serious eye infections if they pass through the infected birth canal.It is highly contagious through sexual contacts.
Question: 27
Differentiate between isomorphic and heteromorphic generation.
Answer: 27
27-68Isomorphic:If gemetophtye and sporophyte generation are vegetatively and morphologically similar then they are called isomorphic generation.
Question: 28
Differentiate between oviparous and viviparous.
Answer: 28
28-68Oviparous: Oviparous are the eggs laying animals like birds.
Question: 29
What is oestrous cycle?
Answer: 29
29-68Oestrous cycle is a reproductive cycle found in all female mammals except human female. In this cycle, the estrogen production prepares the uterus for conception partly and also follicle develops ova.At this stage female needs a physical stimulus of mating for ovulation. She exhibits a desire for mating or is said to be on heat.
Question: 30
Define reproduction.What is its significance?
Answer: 30
30-68Process in which living organism produced their new generation like to themselves is called reproduction.
Question: 31
Define photoperiodism.
Answer: 31
31-68Photo mean light; periodism for duration. Response of plants to the duration of light is called photoperiodism.
Question: 32
Differentiate between parthenocarpy and apomixes.
Answer: 32
32-68Apomixes: In apomixes a diploid cell either from the nucellus or megaspore develops into a functional embryo in the absence of a male gamete.The rest of the ovule develops into seed and ovary into fruit.
Question: 33
Give the function of interstitial cells of testis.
Answer: 33
33-68Interstitial cells produce testosterone. This hormone is essential for the successful production of sperms.
Question: 34
What is after birth? Or What is meant by after birth?
Answer: 34
34-68Within 10 to 45 minutes after birth uterus contracts and separate the placenta from the wall of uterus and placenta than pass out through vagina. This is called after birth.
Question: 35
Define vernalisation. Give its one importance.
Answer: 35
35-68Chilling treatment given to seeds before sowing is called vernalisation.
Its importance is as follows:
Its importance is as follows:
Question: 36
Differentiate between short day plant and long day plants with examples.
Answer: 36
36-68Short day plants: Short day plants flower when the days are short and nights are long e.g, tobacco,soybean.
Question: 37
What are Ovoviviparous?
Answer: 37
37-68In some animals like duck bill platypus internal fertilization leads to internal development of the young ones in a shelled egg and when development is completed shelled egg is laid which hatches the offspring, such animals are called ovaviviparous.
Question: 38
Define terms menstruation and menopause.
Answer: 38
38-68Menstrual cycle:In human females the periodic reproductive cycle is completed in approximately 28 days and involves changes in the structure and function of the whole reproductive system. It is called menstrual cycle.
Question: 39
How seedless fruit are formed?
Answer: 39
39-68Seedless fruit are also called parthenocapic fruits they formed without fertilization. It may be formed naturally as in banana and may formed artificially like seedless grapes.
Question: 40
Distinguish between vernalization and seed dormancy.
Answer: 40
40-68Vernalization: vernalization is the chilling treatment given to seed before sowing is called vernalization.
Question: 41
Describe the process of cloning.
Answer: 41
41-68In animals especially vertebrate animals, a nucleus from the somatic cell is removed and introduced into an egg cell, whose nucleus has been destroyed by using UV light. The egg with transplanted to the parent who has contributed the nucleus.
Question: 42
Name various parts of male reproductive system in male.
Answer: 42
42-68Tastes, penis, Vas defference,epididymus
Question: 43
Define fruit.
Answer: 43
43-68Ripened ovary is called fruit. After the fertilization the cells of ovary wall starts to divide and it develops into complete fruit.
Question: 44
Define labour pain.
Answer: 44
44-68At the time of birth, the reduction of progesterone level stimulates pituitary gland to produce oxytocin. This induces labour pain or contraction of the uterus wall.
Question: 45
What is Apomixes? Or What is meant by Apomixes?
Answer: 45
45-68In apomixes a diploid cell either from the nucellus or megaspore develops into a functional embryo in the absence of a male gamete. The rest of the ovule develops into seed and ovary into fruit.
Question: 46
What are advantage of cloning?
Answer: 46
46-68Cloning has the advantage that all the offspring behave similarly.
Question: 47
Give the role of oxytocin.
Answer: 47
47-68Oxytocin of ovum from the ovary is called ovulation
Question: 48
Give two examples of short day plants.
Answer: 48
48-68Tobacco,Strawberry,Soybean are short day plants.
Question: 49
What are phytochromes?
Answer: 49
49-68Phytochromes are blue light sensitive proteins found in plants. They exist in two form i.e,P660 andP730. They play an important role in photoperiodism.
Question: 50
What are advantages of cloning?
Answer: 50
50-68Cloning has the advantage that all offspring behave similarly. Secondly all the members of a clone are genetically identical to their parents. Good characters of hybrids can be transferred to the next generation without any alteration
Question: 51
What is menopause?At which age it starts.
Answer: 51
51-68The end or complete stop of menstrual cycle is called menopause. It starts at the age of 45 to 50 year
Question: 52
Give importance of photoperiodism in plants.
Answer: 52
52-68Photoperiodism plays an important role in flowering of plants in long and short day plants.
Question: 53
What is the role of P730 phytochrome in flowering?
Answer: 53
53-68P730 induce flowering in long day plant while inhibit flowering in short day plants.
Question: 54
Enlist methods of asexual reproduction.
Answer: 54
54-68Types of asexual reproduction are:-
Question: 55
What are functions of sertoli cells?
Answer: 55
55-68Fluid secreted by sertoli cells provides liquid medium, protection and nourishment to sperms while they are in tubules.
Question: 56
State two methods of asexual reproduction in animals.
Answer: 56
56-68Binary fission is a method of asexual reproduction in which animals like amoeba. During binary fission nucleus elongates and then divides into two nuclei, at the same time cytoplasm divides and two daughter cells are formed.
Question: 57
Name the hormones that stimulate mammary glands for lactation.
Answer: 57
57-68Leutotropic hormone (LTH) and placental lactogen both stimulate mammary glands to produce milk.
Question: 58
What is tissue culture? Explain.
Answer: 58
58-68Growth of plant under aseptic conditions in culture medium is called tissue culture. In this technique tissue cut from the plant could be stimulated by the addition of nutrients, cytokinin, auxin, these cell show continued growth and differentiated in to a new plant.
Question: 59
What is Follicle atresia?
Answer: 59
59-68FSH stimulates the formation of several follicels. Only one of these follicles continues to grow with its primary oocytes while rest breakdown by a degenerative process called follicle atresia.
Question: 60
Give two disadvantages of cloning.
Answer: 60
60-68The entire organism produced by cloning are identical to each other and no genetic variability is produced.
Question: 61
Differentiate between lactation and gestation.
Answer: 61
61-68Lactation: Lactation means discharge or production of milk from the mammary gland after child birth.
Question: 62
How oestrous cycle different from menstrual cycle?
Answer: 62
62-68oestrous cycle: Oestrous cycle is a reproductive cycle found in all female mammals except human female. In this cycle, the estrogen production prepares the uterus for conception partly and also follicle develops ova. At this stage female needs a physical stimulus of mating for ovulation. She exhibits a desire for mating or is said to be on heat.
Question: 63
Differentiate between tissue culture and cloning.
Answer: 63
63-68Tissue Culture: It is the growth of a tissue or plant in an artificial growth culture medium under aseptic conditions.
Question: 64
Define Ovulation.
Answer: 64
64-68Discharge of ovum from the ovary is called ovulation.
Question: 65
Differentiate identical twins and triplets.
Answer: 65
65-68Identical twins: If new born organisms are the product of mitosis and they have same genetic makeup, they are called identical twins.
Question: 66
What is corpus luteum? Give its function.
Answer: 66
66-68The follicle cells after release of the egg are modified to from a special structure called corpus leuteum. It produces progesterone.
Question: 67
What is difference between oogenesis and spermetogensis in humans?
Answer: 67
67-68Oogenesis: In oogenesis, primary oocytes divide meiotically in to secondary oocytes and first polar body. Second meiotic division in the oocytes proceeds as far as metaphase but is not complete until the oocyte is fertilized by the sperm.
Question: 68
What is role of progestrone in pregnancy?
Answer: 68
68-68The end or complete stop of menstrual cycle is called menopause. After menopause female can't produce any more ovum or egg & can't give birth to any child.