(b) Oral Rehydration Solution (ORS). It is similar to bone which Pulp cavity (with nerves and blood vessels) protects the pulp cavity having nerves and blood vessels. It produces a pollen tube that grows through the style and reaches the ovary. Question 40. Answer: The young one develops through mitotic divisions of the zygote so that cells of the grown up individual come to have 46 chromosomes. (a) In binary fission a unicellular organism divides into two equal daughters. (a) Advantages of Sexual Reproduction. Is there any role of liver in digestion of fats? (a) Draw labelled diagram of human male reproductive system. Sexual reproduction also’occurs. Preparation: Under the influence of hormones from pituitary and growing Graafian follicle, the endometrium of uterus thickens, develops blood vessels and glands for nourishing the future embryo. They form a cellular mound which grows into a bud. They are often thick-walled and take part in perennation. (b) In the diagram, label A and B. (a) Surgical methods can be used to create a block in the reproductive system for contraceptive purposes. Gram. Fertilization requires bringing of male gametes to the female gamete which is possible only when pollen grain is brought from the anther to the stigma in the process of pollination. (CBSE Delhi 2008, 2009 C) Types. (a) Asexual reproduction and sexual reproduction Answer: Answer: To produce haploid pollen grains which on growth form pollen tubes, each containing two male gametes. (CCE 2011) Wind pollination is called anemophily. Ex. (d) Bud of Hydra and Bryophyllum. (b) Hydra. It has finger-like outgrowths or villi which are in contact with blood sinuses present in the uterine wall. In binary fission, a parent cell divides into two similar daughters, e.g., Amoeba, Paramecium, Leishmania. (a) large intestine The intense pressure is formed in the stomach when the food is not accepted by the stomach. During reproduction there is formation of new cells which must carry the same amount and type of hereditary information as present in the parent cell. Draw a neat and clean diagram of Amoeba showing the correct location of the following components : nucleus, vacuole, pseudopodia. (CCE 2014) The food of Amoeba are microscopic organisms like tiny plants and animals present in pond water. (a) Asexual reproduction is monoparental, with no gametes, no meiosis and very little variations. Answer: Bisexual. Variations function as preadaptations which help the species to survive in changed environmental conditions. Variability and vitality are helpful to organisms in better adaptability to environment. The other male gamete fuses with the diplod central cell of embryo sac to form primary endosperm cell. 270 days, considered 280 days from the time of previous menstruation. Harmful traits are often kept suppressed because of reshuffling of gene pairs that occurs during gamete formation and fusion. Question 35. #columbiamed #whitecoatceremony” (a) Write the name of the human male reproductive organ that produces sperms and secretes a hormone. (CBSE Delhi 2007) (CBSE Delhi 2016, A.I. The pollen tube carries two male gametes. Question 54. (b) What is the site of fertilization in human beings ? It brings traits of the two parents in the offspring. What is pollination. Question 18. Where are they located ? (b) Site of Fertilization. Answer: Fragmentation. Answer: The various associated glands of digestive system and their role in digestion are as follows. What is vegetative propagation ? Question 37. Carpel—Ovary — Ovule — Embryo sac — Female Germ Cell. Define the following processes : Importance of DNA Copying. Answer: Question 49. Gonorrhoea caused by Neisseria gonorrhoeae. (iii) Development of hair on face, broadening of shoulders and development of larynx with low pitched cracking voice. The simplest form of protein is Name one organism which exhibits this type of reproduction. It produces a nutritive tissue called endosperm. Variations are essential for recognition, individuality and competitiveness. Answer: They occur in contact with blood sinuses of the mother present in the endometrial lining of uterus. (CCE 2014) Answer: 2. It occurs in organisms having simple structure. (CCE 2011) Question 21. What is the information source in the cell nucleus for making proteins. Question 62. It is commonly carried out by the ladies through regular use of oral pills. (b) cellulose gets absorbed in the human blood and converts into fibres It supplies nutrients to the foetus and takes away its waste products. Answer: (a). Answer: 53. Answer: In asexual reproduction, new individuals or daughters are formed through mitotic divisions, e.g., Amoeba. It is Ovum Sperm now known that a single cell may constitute a whole organism as in Amoeba, Fig. (b) The number and type of teeth varries in an adult as compared to the child. Rhizopus. Why are offspring formed by asexual reproduction genetically similar to their parents ? Binary fission occurs under favourable conditions. (b) No. (a) Regeneration is not the same as reproduction as no propagule is formed and no organism will depend on being cut to be able to reproduce. For binary fission, the nucleus or nuclear matter elongates and then divides into two. List four points of significance of reproductive health in a society. Draw diagrams to explain the regeneration that takes place in each of the body parts of Planaria when its body is cut into three pieces. Explain the term “regeneration” as used in relation to reproduction of organisms. Answer: Puberty Changes in Boys. Question 40. (i) List two reproductive parts of a flower. They form haploid (In) male and female gametes through the process of meiosis. Inside your body there is an amazing protectio­n mechanism called the immune system.It is designed to defend you against millions of bacteria, microbes, viruses, toxins and parasites that would love to invade your body.To understand the power of the immune system, all that you have to do is look at what happens to anything once it dies. Answer: (b) Mention the changes a flower undergoes after fertilization. Ovary is transformed into fruit. Describe in brief. Question 14. Question 5. The testes lie in a pouch of skin or scrotum outside the abdomen to provide 1°-3°C temperature lower than that of body. (c), Question 23. (a) kills the harmful bacteria that may enter along with the food, Question 5. Definition: It is a mode of reproduction in which offspring are formed by the process of formation and fusion of gametes. The finger-like projection presents on the inner lining of small intestine is called (b) Prevention of AIDS. Wind picks up the pollen grains of dehisced anthers and disperses the same. Answer: (a) Fruit — Ovary. (b) Can these two methods equated to be the same ? (CCE 2011, 2012) (a) Testosterone. (a) Transportation of absorbed food to different parts of body and their utilisation. Answer: Pollen grain is a spore while ovule is a sporangium. (CCE 2015) Role in Cell Reproduction: DNA carries hereditary information not only for controlling cellular functions but also all the structural and functional traits of organism. Question 7. Cross pollination is the transfer of pollen grains from the anther of one flower to the stigma of another flower. Question 42. Discuss the role of hydrochloric acid secreted by gastric glands. (CCE 2011) It occurs in response to non-fertilization of ovum and non-availability of progesterone hormone. (CCE 2012) In sexual reproduction chromosome number is ^maintained through two processes, gametogenesis and fertilization. Forms embryo. (a) Define germination. (c) Developing embryo obtains nourishment from the mother with the help of placenta. During fertilization, one male gamete fuses with one female gamete. Answer: Plant cells chloroplasts, a large vacuole, and a thick cell wall. (b) make the food soluble How does it occur in plants ? (b) Name the method used by the above leaf for reproduction. Question 59. How does pollination lead to fertilization ? Budding. Replacement of dead individuals and maintaining the organisation in population. (b) Advantages: Question 26. Progestérones— development of uterine lining. In binary fission of Amoeba, the nucleus divides first (before the cleavage of cytoplasm). The plumule, with or without cotyledons, comes out of soil and gives rise to shoot. The haploid gametes have one set of chromosomes (DNAs). True. Ovule is transformed into seed. (ii) How is a unisexual flower different from a bisexual flower ? The seed absorbs moisture through its micropyle. Answer: Answer: It is the formation of new plants from vegetative parts (e.g., stem, leaf, root, bud) of a parent plant. Fertilization cannot occur without the male gamete (brought by germinating pollen grain) coming in contact with female gamete. It makes the bud nutritionally independent. Hormonal methods. (d) Which device prevents implantation by irritating the lining of uterus ? The parent cell bursts open to release the daughter individuals. Bile juice is stored in a sac called, gall bladder, located near its organ of secretion, liver. Answer: Question 41. True. Answer: (CCE 2014) (CBSE A.I. Female Germ Cell. Mention any one external agent which performs this process in some flowers. List any two differences between pollination and fertilization. Students were asked to observe the permanent slides showing different stages of budding in yeast under the high power of microscope. (a), Question 55. This is called tooth decay. (b) Why is digestion of fats difficult as compared to that of other nutrients? Question 3. (b) The piercing and tearing teeth as B Answer: What is sexual reproduction ? Mechanical Barrier Methods. In test tube A, blue black colour appeared because of presence of starch. Unisexual. (a). DNA copying is not error proof. (a) A women had undergone surgical method for preventing unwanted pregnancies. Designed as a three part activityPart 1 - Color copies of a plant and animal cell that are numbered with the main organelles of each cell. Answer: Question 50. It is 270 days (40 weeks or 280 days from the date of last menstruation) . Hormone. He also explained him the proper scientific reason behind it. Spore formation or sporulation Answer: Name its two types. In order to prevent female foeticide, the government has banned prenatal sex determination. 3.1). (c) Impact. The inner lining of stomach secretes mucous hydrochloric acid and digestive juices. (CCE 2011) Longer life span. Male-Sperm, Female-Ovum. Style and stigma are also shed in most of the cases. This process is called rumination. Briefly describe the process of digestion in Amoeba with the help of labelled diagram. (a) Planaria (CCE 2015) (a) Fragmentation. Menstruation lasts for 3-5 days. (b) yeast. Explain with the help of suitable examples, how this explosion can be checked. (a) How do the following contraceptives prevent pregnancy : (b) Mention the possible misuse of surgical method of birth control by some people. (b) Female gamete/egg is not fertilised. Answer: The process is called parturition. Answer: Beginning of growth or sprouting of a propagule like spore, seed or bud is called germination. Answer: Meiosis occurs during gamete formation so that gametes have haploid chromosomes. (b) State the significance of variation in reproduction. Question 1. In human females fertilization occurs in fallopian tube. Question 1. (d) Small intestine, because it carriers the process of digestion and rest are not involved in digestion. Write about the events that occur till the seed formation in the ovary. (d) makes the medium alkaline Differences Between External and Internal Fertilization. Answer: In Bryophyllum, vegetative propagation occurs through the agency of leaves that fall on moist soil. Pollination: It is the transfer of pollen grains from anther to the stigma. Answer: (CCE 2015) (a) Identify A, B and C in given diagram and write their functions, Definition: Variation is differences in structure, physiology and other characters found in the individuals of the same organism. After a few days, endometrial lining breaks. Question 9. Male Germ Cell. They may not protect individuals under adverse conditions but survival of species depends upon pre-adaptive variations. Question 36. Question 46. (iv) Dirty fingers or unwashed objects must be avoided to put in the mouth. Testes are located outside the abdominal cavity (in testicle behind penis) as maturation of sperms requires a temperature lower by 2°C than that of the body. Question 14. Answer: Question 18. The radicle grows, passes out of the seed and enters the soil as root. Question 37. The finger-like outgrowths of Amoeba helps to ingest food. We should not eat hurriedly because if we ingest food in hurry or we talk or laugh while eating we experience hiccups, coughing or choking sensation. Differentiate between the following : simpler form, digestion, Question 4. Give one example of each. A very large number of spores develop from an individual. Differentiate between (a) Name an organism in which binary fission occurs in a definite orientation.