1. What are the advantages of sexual reproduction over asexual reproduction?
Answer: Sexual reproduction is better than asexual reproduction. Its main advantages are –
(i) Due to fusion of sperm and egg in sexual reproduction, the paternal trait is transferred by DNA to the member of the present generation, which is more powerful for survival whereas in asexual reproduction due to the presence of a single DNA, survival The chances for survival are reduced.
(ii) In sexual reproduction, there must be some difference in both the copies of DNA, as a result of which the difference is definitely visible in the member organism of the new generation whereas in asexual reproduction there is no difference. If there is a difference in it for any reason, then the soul dies.
(iii) Sexual reproduction is very helpful in evolution whereas asexual reproduction is not helpful in evolution.
2. What is called regeneration (regeneration)? Present the process of emergence in Planaria with the help of a diagram.
Answer: In this type of reproduction, due to some reason the body of the organisms-natural cause or artificial reason-is fragmented into two or more pieces and each segment develops its lost parts and transforms into a fully developed new organism. and leads a normal life. For example, this type of reproduction is found in Spirogyra, Hydra and Planaria etc.
3. What are the types of reproduction?
Answer: There are two types of reproduction- (1) Asexual reproduction (2) Sexual reproduction
(1) Asexual Reproduction- In this method only one individual of the organism takes part and gametes do not participate in it. Organisms produced by this method are exactly similar to the parents in genetic properties. This type of reproduction mainly takes place in low quality plants and animals.
Its types are as follows-
(i) fission-fission, multiple fission, (ii) budding, (iii) fragmentation or regeneration, (iv) sporogenesis, (v) vegetative propagation.
(2) Sexual reproduction – In this method two different sexes i.e. male and female take part. In which zygote is formed as a result of fusion (fertilization) of male gamete (sperm) and female gamete (egg). This zygote develops, divides and differentiates into an adult organism which is different from the parent.
4. Write the difference between sexual and asexual reproduction.
Answer : Following are the differences between asexual and sexual reproduction-
asexual reproduction
(i) Only one cell or one parent participates in this process.
(ii) The parent may be the whole body or a single cell or a multiplication unit.
(iii) The offspring produced by this process are genetically identical to the parents.
(iv) Only mitosis takes place in this process.
(v) There is no formation of genitalia.
sexual reproduction
(i) In this process two cells or two gametes, which arise from one parent or two different parents, are shared.
(ii) In this, the reproductive unit is called gamete which is unicellular and haploid.
(iii) In these, the progeny are often different from their parents.
(iv) Meiosis and fertilization are important in this process.
(v) In this, the production of genitals takes place mainly.
5. What is the meaning of external fertilization and internal fertilization?
Answer: External fertilization – When the fusion of male and female gametes takes place outside the body of the female, then this fusion is called external fertilization, as in frog, both male and female organisms mate and release their gametes into the water. The sperm fertilizes the eggs in the water itself.
In external fertilization, there is a greater chance of the eggs being destroyed due to the absence of internal defences, so in order to be certain that some eggs can be fertilized, the female produces more eggs.
Internal Fertilization – In many organisms, such as dogs, cats, cows, insects, humans, reptiles, birds and mammals, the male releases his sperms inside the body of the female. Sperm fertilizes the eggs inside the female's body. Such fertilization is called internal fertilization.
6. How does the fetus get nutrition in the mother's body?
Answer: At the time of copulation, the sperms are established in the vaginal tract, from there after meeting in the ovary, the fertilized egg gets installed in the uterus and starts dividing. The inner lining of the uterus becomes thick and the blood flow also increases for the nourishment of the foetus. The embryo gets its nutrition from the mother's blood, for this there is a special structure, which is called placenta. It is a saucer-like structure embedded in the wall of the uterus. It consists of spurs in the A tissue on the embryonic side. There are blood vessels in the mother's tissues that cover the septum. It transports glucose, oxygen and other substances from the mother to the fetus.
Provides a large area for transfer. Wastes are produced by the developing embryo which are then disposed of by transfer to the mother's blood through the placenta. In this way the fetus gets nourishment in the mother's body.
7. Describe the various measures used for population control. What are the different methods of contraception?
Answer: Following are the various measures used for population control –
Natural method - If intercourse is stopped for a few days, then during that time the semen will not enter the woman's vagina, due to which there will be no possibility of fertilization.
Mechanical methods – The most effective method is the use of condoms for men. It also protects men and women from deadly sexually transmitted diseases like AIDS. There are family planning tools available for women like diaphragm, copper-T and loop.
Chemical Methods – In such methods, means made from different chemicals are used.
Surgical Methods – Under this, vasectomy is done. This type of surgery performed in women is called female sterilization.
Social awareness – Publicity of the effect of population growth on human society and the use of various means for its control, through newspapers, magazines, television, posters or other powerful means of publicity, will increase human awareness of population control.
8. Describe the structure of the fallopian tubules.
Answer: The fallopian ducts are a pair of ducts that start from the upper part of the ovary and go down and finally connect with the uterus. The apex of each fallopian duct is like a wide funnel that helps the egg to enter the fallopian duct. The walls of the fallopian tubes are fleshy and contractile. Its inner surface is covered with cilia, which carry the egg to the uterus through the fallopian duct.
human female reproductive system
9. Draw a labeled diagram of the female reproductive system.
human female reproductive system
10. What is the role of sperms and prostate gland?
Answer: The prostate gland is a small, almost circular gland located at the base of the bladder. Prostatic fluid is secreted from the prostate gland. The spermatic fluid and the seminal fluid combine to form semen. Semen has a special smell because of the pure fluid. Purustha fluid stimulates the sperms (male gametes) of Veer. Prostate and sperms put their secretions in the vasculature, due to which the sperms come in a liquid medium, due to which they are easily transferred and this secretion also provides nutrition to them. Sperm are microscopic structures consisting mainly of genetic material and a long tail that helps them to swim towards the female germ cell.
human male reproductive system
11. Describe the methods of contraception.
Answer: Following are the methods of contraception –
In women –
(i) intrauterine device,
(ii) vaginal diaphragms, chemo-jelly etc.,
(iii) operation method,
(iv) contraceptive pills prepared from hormones,
(v) implantation of copper-T in the uterus does not nourish the fetus finds.
Tubectomy (sterilization)
in male
Tubectomy (sterilization)
(i) Sterilization
(ii) Condoms, etc. are used for contraception.
Birth regulation is done by operation. Population control is done by sterilization (cutting the fallopian tubes) in women and vasectomy (cutting the spermatic ducts) in men.
12. How is binary fission different from multiple fission?
Answer: In diffusion fission, two are formed by fragmenting from one individual. In this method, the cell or body grows and divides into two equal parts. First the nucleus divides into two identical daughter nuclei by mitosis or mitosis and finally the cytoplasm also divides into two equal parts. This gives rise to two progeny organisms. Example-Bacterium, Paramecium, Amoeba, Chlamydomonas, Euglena, Yeast, etc.diffusion in amoeba
In multiple fragmentation, one individual fragments and produces many individuals. Under these unfavorable conditions some unicellular organisms form a hard wall, cyst or cyst around their body or cell. The nucleus within the cell divides repeatedly to form daughter nuclei. After this, a covering of cytoplasm is formed around these nuclei. Thus many daughter cells are produced inside the cyst. Upon arrival of favorable conditions, the cyst bursts and the daughter cells emerge and develop. Example- amoeba, plasmodium, low-grade algae etc.
multiple fragmentation in amoeba
Hence, binary fission is different from multiple fission.
13. What is the difference between the auxiliary and essential parts of a typical flower?
Answer: There are four types of flowers in a typical flower –
(i) Calyx
(ii) Corolla
(iii) Pumang (Androecium)
(iv) Gynoecium
Out of these, the two outer chakras i.e. Bahyadalpunja and Dalpunja are called accessory organs and the inner two chakras i.e. Pumanga and Jayang are called essential organs. Along with making the flower attractive, the auxiliary organs also protect the essential organs and the essential organs perform the function of reproduction. This is the difference between them.
longitudinal cut of flower
14. List the complete processes from pollination to seed formation in a typical flowering plant.
Answer: After pollination, the pollen grains reach the stigma, where they absorb nutrients and grow. The pollen tube emerges from the pollen grain, which passes through the stigma and enters the ovule. In the ovule, the male gamete combines with the ovum to form the zygote or zygote, which eventually form the embryo. After fertilization the ovary and ovule develop into fruit and seed respectively.stigma
15. How is pollination different from fertilization?
Answer: Pollination is the process of the pollen grains coming out of the anther and reaching the stigma of the same flower or other flowers of that species. It occurs in two ways - by self-pollination and by cross-pollination. Self-pollination occurs only in hermaphrodite plants, such as sunflower, balsam, portulaca etc. For this some external agent or agent is needed which works to transport the pollen grains from the flower anther of one plant to the stigma of another flower. These external factors can be any insects, birds, bats, humans, air, water etc. Some special stages in flowers for cross-pollination. They are so that only cross-pollination is possible in them. This is the process of pollination.
Fertilization occurs after the pollen grains reach the stigma. The fusion of male gamete and female gamete is called fertilization. In this, a tube develops from the pollen grain and reaches the ovule through the stigma.
germination of pollen grains on the stigma
16. Describe the process of fertilization in flowering plants.
Answer: After the process of reaching the stigma (pollination) of the pollen grains in flowering plants. Fertilization takes place. The fusion of male gamete and female gamete is called fertilization. After reaching the stigma, the pollen grain absorbs nutrients from the surface of the stigma and develops a pollen tube. This pollen tube enlarges and enters the ovule through the stigma. The male gamete emerges from the pollen tube and fuses with the female gamete located in the ovule. After fertilization, the zygote divides and develops into an embryo. After fertilization, ovaries develop into fruits and ovules develop into seeds. fertilization in flowering plants
17. What is pollination? What will be the effect on pollination if it rains.
Answer: The transfer of pollen grains from the anther of the stamen to the stigma of the pistil is called pollination. When this transfer of pollen grains occurs between the same flower or two flowers of the same plant, then it is called self-pollination. Self pollinating flowers are mostly white. When pollination takes place between flowers of two different plants of the same species, it is called cross pollination. But the pollinating flowers are colorful and shiny. Pollination involves the transfer of pollen grains by insects, by wind and by water. Seeds and fruits are formed as a result of pollination. When it rains, the process of pollination slows down.
18. Why is it necessary to make a replica of Dr.N.A. for reproduction?
Answer: Making copies of DNA is necessary for reproduction because they are responsible for the formation of proteins that carry the specific information of reproduction. DNA is located on the chromosomes which are present in the nucleus of the cell. For each type of specific information, a specific type of protein is responsible. DNA molecules carry messages of genetic properties that are passed from parent to offspring.
19. What is the importance of DNA replication in reproduction?
Answer: Two copies of DNA are made in the germ cell and they must be separate from each other. By keeping a copy of DNA in the original cell, the second replica cannot be ejected from it because the second replica will not have the organized cellular structure to maintain the bio-processes. Therefore, along with the replication of DNA, other cellular structures are also created. After this the replicas of the DNA are separated. As a result, one cell divides to form two cells. The daughter cells, despite being similar, differ from each other in some way or the other. These differences in reproduction are the basis of biological evolution and this is its importance in reproduction.
20. Why is vegetative propagation used to grow some plants?
उत्तर⇒Some parts of the plant like root, stem and leaves develop under suitable conditions to produce a new plant. Unlike most animals, single plants use this ability as a method of reproduction. However, techniques of vegetative propagation like grafting or planting are also used in agriculture. Some examples are sugarcane, rose or grapes. Plants grown by vegetative propagation produce flowers and fruits in less time than those grown by seed. This method is useful for growing plants like banana, orange, rose and jasmine which have lost their ability to produce seeds. Another advantage of vegetative propagation is that all the plants thus produced are genetically identical to the parent plant, Because they do not require sexual reproduction, due to which variation does not arise. Similarly, some buds develop on the core of the leaves of Bryophyllum and fall into the soil and develop into a new plant.
Bryophyllum leaf with buds
21. What changes are seen in girls at the time of puberty?
Answer: Puberty means adolescence. Hair starts coming between the armpit and both the thighs and near the external genitalia of girls. Soft hair starts growing on the legs and arms. The skin starts to become somewhat oily. In this stage, pimples also start coming out on the face. Breasts begin to bulge. The color of the skin around the nipple located in the center of the breast starts thickening. The menstrual cycle starts. At this stage, there is an attraction towards people of the opposite sex like yourself. This stage of puberty is called puberty.
22. Variation in organisms is beneficial for the species but is not necessary for the individual, why?
Answer: By using their reproductive capacity, organisms take their place or niches in the population ecosystem. The inhibition of DNA replication during reproduction is critical to an organism's anatomical structure and design, making it capable of specialized niches. Therefore, the stability of the population of a species is related to reproduction.
However, many changes can occur in the niche which are beyond the control of the living beings. Earth's temperature can be low or high, changes in water level or the collision of a meteorite are some examples of this. If a population is favorable to its niche and some drastic changes take place in the niche, then in such a state the complete destruction of the society is also possible. But if there is variation among the organisms of the population then they have some chance of survival. Therefore, if there is a population of bacteria found in temperate water and the temperature of the water rises due to global warming, then most of the bacterial individuals will die, but only a few viruses with the ability to resist heat survive and grow. . Therefore, variations are useful in maintaining the survival of the species.
23. What is reflex action? Describe it with the help of diagram.
Answer: Reflex actions are responses to autonomous stimuli . These actions take place without the will of the brain. Hence these are involuntary actions. These are very clearly mechanical types.by handWhen a bright light falls on our eyes, the thinness of our eyes suddenly starts getting smaller. This action happens immediately and without the will of our brain.
Reflex actions are involuntary actions by muscles controlled by the spinal cord in response to a stimulus. If suddenly a pinch is made in any part of the body, then this stimulus received by the senses stimulates the efferent nerve fibers of this motor nerve region. The nerve fiber carries this stimulus to the spinal cord through the dorsal tract of the spinal nerve.
From the spinal cord it reaches one or more efferent nerve fibers through the ventral tract of stimulation. Efferent nerve fibers stimulate the dominant organs. To prick the pin. Immediately after this the creature takes away the dominant part. The path of the stimulus from the sensory organ to the dominant organ is called reflex arc.
The reflex arc forms the functional unit of the nervous system.
occurs in a reversible arc.
(i) Sensory organ – The organ or place that receives the stimulus.
(ii) Afferent Nerve Fibre- This sensory impulse is carried from the sensory organs to the central system, such as the brain or spinal cord.
(ii) Central Nervous System- Part of the brain or spinal cord.
(iv) Efferent or Motor Nerve- It carries motor impulses from the central nervous system to the effective organs, such as muscles or glands.
(v) Effector – This nerveless part like glandular muscles where motor inspiration ends and response is given. Task-reversing action helps the motivator to respond quickly and also frees the brain from overwork.
24. Draw a clean nomenclature of the human brain.
उत्तर⇒Head
25. Briefly describe the spinal cord.
उत्तर⇒spinal cordThe medulla oblongata extends from the sacrum of the skull down through the middle of the vertebrae of the spinal cord.
This is called the spinal cord or spinal cord. Above it are three membranes called diameter, arachnoid and piomete in the same way as above in the brain. 31 pairs of spinal nerves emerge at certain distances from the spinal cord. Its length is about 45 cm.
Functions of the spinal cord
(i) It serves as the coordination center for simple reflex actions such as response to a knee jerk, spinal reflexes, such as contracture of the bladder, etc.
(ii) It acts as a communication between the brain and the spinal cord.
26. Describe the human male genitals.
Answer : The following organs come in the human reproductive system -
(i) Testes - There is a pair of testes in humans which are closed in the testicular sac. Sperm are produced in the testes. Sperm live for about 48 hours after being released from the testis. The production of sperms is called spermatogenesis. Testicular cells provide sperms with a temperature of 1-3°C below body temperature.
The functions of testis are-
(a) production of sperm, and (b) male sex, production and secretion of the hormone-testosterone.
If the testes remain in the body cavity, then sterility occurs.
(ii) Epididymis – It is a tubular structure which is firmly attached to the testis. It is attached to the seminiferous tubules and serves as a storage house for spermatozoa.
(iii) Spermatozoa – From the epididymis, spermatozoa come into the scrotum through the spermatic duct where they are fully mature and some secretions are mixed in them.
(iv) Prostate gland – This gland secretes some specific odor or secretion which gets mixed with the spermatic cord.
(v) Mantra Marga – This is the passage through which urine comes out. This urinary tract originates from a muscular organ called the penis. The penis is used to pass urine as well as to expel sperms (sperms).
27. Describe any three artificial methods of vegetative propagation in plants.
Answer: Three artificial methods of vegetative reproduction The main artificial methods of vegetative propagation are planting, grafting, pressure grafting and tissue culture.
(i) Cutting - In this method, by making use of Rana, leaves and roots, in which there are two plants, they are buried in the ground. After some time roots and shoots develop from them. Examples are roses and sugarcane, hibiscus and grapes. The axillary buds separate the stem pieces from the mother plant.pen piece
(ii) Applying pressure – It is also called applying gooty. The stem parts of some plants are close to the ground. By bending them, they bury them in the soil in the ground. There itself . But after some time the roots come out. Separate it from the mother plant. In this way a new plant is obtained. Example- Lemon, Mogra, Guava, Hibiscus, Jasmine, Bougainvillea etc.leaves
(iii) Bud planting – In this method, a slant cut is made on the stem of the plant of the ordinary species to the depth of the bark. In the same cut, the bud of a good plant is planted from a plant of the same species. After some time the bud attaches to the plant and a new branch is formed. Cut it apart. This method is adopted in rose, grape, custard apple, orange etc.bud
28. Describe menstruation.
Answer: Menstruation in women – In women this cycle starts at the age of 13-15 years. This is puberty. Menstruation in women is of 28 days. This time is the full life span of the ovum.
Its stages are as follows-
(i) By the 1st-5th day the old egg comes out at the time of menstruation. Growth of new egg starts in the ovary.
(ii) By day 6-12, the egg matures from the ovary to become a Graffian follicular.
(iii) On day 13-14, the Grafian follicular comes out of the ovary and reaches the oviduct. This is called ovulation.
(iv) On day 15-16, the egg comes to the oviduct and then to the uterus and waits to meet the sperm. If fertilization takes place in the meantime, the egg is converted into a zygote, which develops into an infant in 9 months.
(v) If fertilization does not take place, it becomes dormant by the 17-28th day. Comes out of menstruation after 28 days.
(vi) This cycle is controlled by the hormones estrogen and progesterone. Menopause in women lasts for 45-50 years. Adolescence in boys begins at the age of 13 to 15 years. There is no cycle in them. Sperm formation takes place throughout life.
29. What is Mukulan? How does reproduction take place in hydra and sponges by budding?
Answer: An vertical structure is formed on the body which is called Mukul. The nucleus of the body gets divided into two parts and one of them comes in the nucleus. The mukul separates from the parental organism and grows and becomes a fully developed organism. Like yeast, hydra and leukosolinia (sponge) etc.Mukul
30. What are the different methods of contraception?
Answer: In order to regulate the birth of children, it is necessary that there is no fertilization of the female.
Following are the main contraceptive methods for this –chemical method
(i) Chemical method: Many types of chemical substances can inhibit female fertilization. Anti-heat pills are used by women. Foam tablets, jellies, different types of creams etc. do this job.
(ii) Surgery – Fertilization is prevented by sterilization in males and also by sterilization in females. of men. In surgery, the spermatic cord is cut and tied so that the sperm produced in the testes are not able to come out. In women, the oviduct is cut and tied so that the eggs made in the ovary do not enter the uterus.
Urinary
(iii) Physical method – By various physical methods the sperms are stopped from going into the uterus of the woman. The use of prevention in sexual contact etc. comes under this.
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