An important facility for 12th class students preparing for short questions biology 12th class chapter 5 of BISE. Get hundreds of questions to prepare and get better marks in 12th biology
0
Our database contains a total of 0 questions for biology Short Questions. You’ll prepare using this huge databank.
Question: 1
What are apical meristems?
Answer: 1
1-49These are the cells which are capable of cell division and are involved in the primary growth of plants.
Question: 2
How do quantity and quality of light effect plant growth?
Answer: 2
2-49Light plays important role in the growth of plants:
Quality of light: The red light favors elongation of cells and blue light enhances cell division but retards cell enlargement. Similarly ultraviolet rays also retard cell elongation.
Quantity of light:Duration of light affects the growth vegetative & reproductive structures. It also plays a role in inducing or suppressing flowering. The phenomenon is termed as photoperiodism.
Quality of light: The red light favors elongation of cells and blue light enhances cell division but retards cell enlargement. Similarly ultraviolet rays also retard cell elongation.
Quantity of light:Duration of light affects the growth vegetative & reproductive structures. It also plays a role in inducing or suppressing flowering. The phenomenon is termed as photoperiodism.
Question: 3
Differentiate between primary growth and secondary growth in plant.
Answer: 3
3-49Primary growth: occur due to the activity of apical meristem which results increase in length or height of plant.
Question: 4
Differentiate between apical meristem and lateral meristem.
Answer: 4
4-49Apical meristem:Apical meristem found at the tips of shoot and root.The cells of apical meristem has ability to divide throughout plant life,These are basically related to extension of plant body.
Question: 5
Differentiate between growth and development.
Answer: 5
5-49Growth:In in size of an organism is called growth.It is an irreversible change.
Question: 6
Differentiate between growth and embryonic development.
Answer: 6
6-49Growth:Growth is the permanent and irreversible increase in size that occurs as an organism matures.
Question: 7
What is open growth? Discuss.
Answer: 7
7-49Plants have growth pattern called open growth which means throughout life plants add new organs such as branches,leaves and roots, enlarging from the tip of roots and shoots.
Question: 8
What is growth? Mentions its types.
Answer: 8
8-49Increase in size of an organism is called growth. It has two types
Question: 9
Define apical and intercalary meristem.
Answer: 9
9-49Apical meristem: Apical meristem found at the tips of shoot and root. The cells of apical meristem has ability to divide throughout plant life. These are basically related to extension of plant body.
Question: 10
Differentiate between determinate and indeterminate growth.
Answer: 10
10-49Determinate growth: in higher plants growth occur at certain points called meristem and whole body do not grow in different planes such a growth is called determinate growth.
Question: 11
What are the internal factors which affect the process of growth?
Answer: 11
11-49internal factors which are involved in plant growth are hormones,water ,nutrition,vitamins.
Question: 12
Give the effect of temperature on plant growth.
Answer: 12
12-49Normal rate of growth increases with rise of temperature and decrease with decrease in temperature. For maximum growth the optimum temperature is 25 to 30oC and it is least at 5-10oC. But at very high temperature 35 to 40oC the rate of growth stops and plant may dies.
Question: 13
What is difference between inhibitory effect and compensatory effect?
Answer: 13
13-49Inhibitory effect: Auxin diffuses from apical buds to the lateral buds or branches which inhibit the growth of lateral shoots is called inhibitory.
Compensatory effect: When the apex is cut and diffusion of auxin is stopped to the lateral buds it releases the lateral buds from apical dominance is called compensatory effect.
Compensatory effect: When the apex is cut and diffusion of auxin is stopped to the lateral buds it releases the lateral buds from apical dominance is called compensatory effect.
Question: 14
What is morula?
Answer: 14
14-49After fertilization of egg it divides repeatedly by mitotic division resulting in a ball of cells called morula
Question: 15
What is primitive streak?
Answer: 15
15-49In the chick the mesodermal cells do not invaginate but migrate medially and caudally from both sides and create a mid line thickening called primitive streak.
Question: 16
Write practical application of apical dominance.
Answer: 16
16-49It can be used to produce smooth woody stem.
It is also used to increase the storage life of potato from 1 to 3 years.
It is also used to increase the storage life of potato from 1 to 3 years.
Question: 17
What is compensatory effect?
Answer: 17
17-49The removal of apex from the apical tip release the lateral buds from the apical dominance,it is called compensatory effect.
Question: 18
Give role of temperature in plant growth.
Answer: 18
18-49Temperature influences the growth within a certain range (0-35oC). Normally rate of growth increase with rise of temperature and decrease with decrease in temperature. For maximum growth the optimum temperature is 25-35oC and it is least at 5-10oC. But at very high temperature 35 to 40oC the rate of growth stops and plant may dies.
Question: 19
Define Growth correlations.
Answer: 19
19-49Development of plant is usually correlated with its growth and different organs grow at different rates in different directions and the development of different parts takes place.This is called growth correlation.
Question: 20
Define Apical Dominance.Give its cause.
Answer: 20
20-49In many plant species only apical bud grows while growth of lower axillary buds is inhibited this process is called apical dominance.
Question: 21
How are opaca differs from area pellucida?
Answer: 21
21-49Area pellucida: Central cells of blastoderm can be separated from yolk and giving the area of translucent appearance called Area pellucida.
Area opaca: The peripheral part of balstderm where the cells are unseparated from the yolk is called area opaca.
Area opaca: The peripheral part of balstderm where the cells are unseparated from the yolk is called area opaca.
Question: 22
What is blastoderm?
Answer: 22
22-49The discoidal cap of cells above the blastocoel is called blastoderm.
Question: 23
Differentiate between epiblast and hypoblast.
Answer: 23
23-49Epiblast: During gastrulation blastoderm splits into two layers,an upper layers of cells is called epiblast.
Hypoblast: Lower layer of cells is called hypoblast.
Hypoblast: Lower layer of cells is called hypoblast.
Question: 24
Define blastocoel and neurocoel.
Answer: 24
24-49At blastula stage there is a segmentation cavity formed called blastocoel which is formed by the separation of cell.
Question: 25
Differentiate between neurula and neurocoel.
Answer: 25
25-49Neurula: In the embryo of 24 hrs the neural folds are clearly visible,at this stage embryo is called neurula.
Question: 26
Differentiate between primary organizer and primary induction.
Answer: 26
26-49Primary organizer: The area of the dorsal lip which induces the development of secondary embryo in the host is called primary organizer.
Question: 27
Explain embryonic induction.
Answer: 27
27-49Capacity of some cells to induce a specific developmental response in other cells is wide spread phenomena,this is called embryonic induction.
Question: 28
Name two layers of lateral plates of mesoderm.
Answer: 28
28-49The lateral plate of mesoderm splits into two layers named as somatic mesoderm and splanchnic mesoderm.
Question: 29
What is ceolom?
Answer: 29
29-49Coelome is called body cavity. It is formed by the splitting of mesoderm into somatic mesoderm and splanchnic mesoderm.
Question: 30
What is cleavage?
Answer: 30
30-49Immidiately after fertilization, egg undergoes a series of mitotic division called cleavage.
Question: 31
How neural plate is formed?
Answer: 31
31-49on the dorasal surface of the gastrula,over the notochord,presumptive neural ectoderm is present in the form of band. As gastrula elongates,the band thickens to from a neural plate.
Question: 32
What is discoidal cleavage?
Answer: 32
32-49in bird's egg the process of cell division is confined to the small disc of potoplasm laying on the surface of yolk at the animal pole.This type of cleavage is called discoidal cleavage.
Question: 33
What is grey crescent?Give its importance.
Answer: 33
33-49Grey crescent is the pigment free area that appears at the time of fertilization.
Question: 34
Give to role of cytoplasm in the development of an Ascidian.
Answer: 34
34-49For types of cytoplasm in Ascidian are
i) Clear cytoplasm produces larval epidermis
i) Clear cytoplasm produces larval epidermis
Question: 35
How aging can be slow down?
Answer: 35
35-49Aging can be slow down by
i) Taking regular exercise ii) By taking balanced diet iii) Avoiding smoking and alcohol.
i) Taking regular exercise ii) By taking balanced diet iii) Avoiding smoking and alcohol.
Question: 36
Define aging? Write its two signs.
Answer: 36
36-49Negative physiological changes in an organism are called aging. Its two symptoms are:
Wrinkled skin and grey hairs.
Wrinkled skin and grey hairs.
Question: 37
What are metabolic defects and give two example?
Answer: 37
37-49Bones are malformed and one organ or its part is missing or it may be repeated.
Question: 38
What are teratogens? Give an example.
Answer: 38
38-49Anything which interferes with the normal process of development is the factor causing abnormalities and are known as teratogens.
For Example:Radiation,Maternal infections,Chemicals and drugs.
For Example:Radiation,Maternal infections,Chemicals and drugs.
Question: 39
Write about cleavage and discoidal cleavage.
Answer: 39
39-49The series of mitotic divisions after fertilization of egg is called cleavage.Process of cell division is confined to the small disc of protoplasm laying on the surface of yolk at animal pole.This type of cleavage is called discoidal cleavage.
Question: 40
What are neoblasts and their role? Or What are neoblasts?
Answer: 40
40-49Neablasts are unspecialized cells which are always present in the body of adult and are mobilized to the site of ampuation,where they are differentiated into specialized cells.
Question: 41
What is regeneration?
Answer: 41
41-49Formation of lost parts of the body is called regeneration. For example if arm of star fish is cut, it will be regenerated or reformed.
Question: 42
Define Gerontology.
Answer: 42
42-49Gerontology is the study of aging. It also deals with the causes of aging and measures by which aging can be slowed.
Question: 43
Differentiate between gerontology and teratology.
Answer: 43
43-49Gerontology: Study of aging is called gerontology.
Question: 44
Define teratology and teratogens.
Answer: 44
44-49Study of abnormal development is called teratology. Factors causing abnormal development are called teratogens.
Question: 45
What role is played by clear cytoplasm and yellow cytoplasm in animal development?
Answer: 45
45-49Clear cytoplasm produces larval epidermis and yellow cytoplasm produces muscle cells.
Question: 46
Define Regeneration.Give one example.
Answer: 46
46-49The ability to regain or recover the lost part or injured part of the body is called regeneration.For Example if lobster loses its pincer claw a new claw regenerates.
Question: 47
Differentiate maturation from differentiation.
Answer: 47
47-49Maturation:During maturation,the final size of a given type of a cell is attained.The cells which develop into pith,cortex and certain other tissues do not elongate further.
Question: 48
Name the phase of plants growth.
Answer: 48
48-49Phases of plants growth are:
i) Phase of cell division ii) Phase of elongation iii) Phase of maturation iv) Phase of differention.
i) Phase of cell division ii) Phase of elongation iii) Phase of maturation iv) Phase of differention.
Question: 49
What are intercalary meristems?Give their role.
Answer: 49
49-49These are the parts of apical meristem which get separated from apex by permanent issues.They play important role in the production of leaves and flowers.
