Q 1 – Asexual reproduction takes place through budding in
(a) Amoeba
(b) Yeast
(c) Plasmodium
(d) Leishmania
(b) Asexual reproduction in Hydra and yeast takes place by budding.
Q 2 – The ability of a cell to divide into several cells during reproduction in Plasmodium is called
(a) budding
(b) reduction division
(c) binary fission
(d) multiple fission
(d) Multiple fission Organisms divide into many daughter cells simultaneously, e.g. Plasmodium.
Q 3 – The anther contains
(a) sepals
(b) ovules
(c) carpels
(d) pollen grains
(d) Anther is the male reproductive part in plants. It contains pollen grains, having male germ cells.
Q 4 – Characters that are transmitted from parents to offspring during reproduction show
(a) only similarities with parents
(b) only variations with parents
(c) both similarities and variations with parents
(d) neither similarities nor variations
(c) both similarities and variations with parents
Q 5 – Which among the following diseases is not sexually transmitted?
(a) Syphilis
b) Hepatitis
(c) HIV-AIDS
(d) Gonorrhoea
(b) Hepatitis
Q 6 – Which of the following is not a part of the female reproductive system in human beings?
(a) Ovary
(b) Uterus
(c) Vas deferens
(d) Fallopian tube
(c) Vas deferens is a part of male reproductive system in humans.
Q 7 – A feature of reproduction that is common to Amoeba, Spirogyra and yeast is that
(a) they reproduce asexually
(b) they are all unicellular
(c) they reproduce only sexually
(d) they are all multicellular
(a) they reproduce asexually
Q 8 – Which among the following statements are true for unisexual flowers?
I. They possess both stamen and pistil.
II. They possess either stamen or pistil.
III. They exhibit cross-pollination.
IV. Unisexual flowers possessing only stamens cannot produce fruits.
(a) I and IV
(b) II, III and IV
(c) III and IV
(d) I, III and IV
(b) II, III and IV
Q 9 – Length of pollen tube depends on the distance between
(a) pollen grain and the upper surface of the stigma.
(b) pollen grain on the upper surface of stigma and ovule.
(c) pollen grain in anther and the upper surface of the stigma.
(d) the upper surface of stigma and lower part of the style.
(b) pollen grain on the upper surface of stigma and ovule.
Q 10 – Which among the following statements are true for sexual reproduction in flowering plants?
I. It requires two types of gametes.
II. Fertilisation is a compulsory event.
III. It always results in formation of zygote.
IV. Offsprings formed are clones.
(a) I and IV
(b) I and II
(c) I, II and III
(d) I, II and IV
(c) I, II and III
Q 11 – Factors responsible for the rapid spread of bread mould on slices of bread are
I. large number of spores.
II. availability of moisture and nutrients in bread.
III. presence of tubular branched hyphae.
IV formation of round-shaped sporangia
(a) I and III
(b) II and IV
(c) I and II
(d) III and IV
(c) I and II
Q 12 – During adolescence various changes occur in the body of humans. Mark one change associated with sexual maturation in males.
(a) Loss of milk teeth
(b) Increase in body height
(c) Cracking of voice
(d) Weight gain
(c) Cracking of voice
Q 13 – What in your opinion could be the best reason to explain why menstruation is not taking place in a healthy woman?
(a) Early release of ovum
(b) Psychological reason
(c) Fertilisation of ovum
(d) Build up of female sex hormones in the blood stream
(c) Fertilisation of ovum
Q 14 – The correct sequence of reproductive stages seen in flowering plants is
(a) gametes, zygote, embryo, seedling
(b) zygote, gametes, embryo, seedling
(c) seedling, embryo, zygote, gametes
(d) gametes, embryo, zygote, seedling
(a) gametes, zygote, embryo, seedling
Q 15 – Offsprings formed by asexual method of reproduction have greater similarity among themselves because
I. asexual reproduction involves only one parent.
II. asexual reproduction does not involve gametes.
III. asexual reproduction occurs before sexual reproduction.
IV. asexual reproduction occurs after sexual reproduction.
(a) I and II
(b) I and III
(c) II and IV
(d) III and IV
(a) I and II
Q 16 – Two flowers are identified by a botanist with the following features that flower A is having the only stamen and flower B is having both stamen and pistil. Which of the following statements is correct?
(a) Flower A will bear seeds and flower B cannot bear seeds after fertilization.
(b) Flower A will produce pollen grains and flower B cannot produce pollen grains.
(c) Flower A cannot be fertilized and flower B can show fertilization.
(d) Neither flower A and nor flower B can show self-pollination.
(c) Flower A cannot be fertilized and flower B can show fertilization.
Q 17 – In the human female reproductive system where does fertilization occur?
Oviduct or Fallopian tube.
Q 18 – Name the male and the female gametes in human beings.
The male gamete is called sperm and the female gamete is called ovum in human beings.
Q 19 – Name the part of Bryophyllum where the buds are produced for vegetative propagation.
Leaf notches.
Q 20 – Define menopause.
At the age of around 45-50 years, the ovaries of the females stop producing ova.
The stoppage of menstrual flow and other events like the changes in the hormonal composition is known as menopause.
Q 21 – What is budding? Name two organisms that reproduce asexually by budding.
In budding, a small part of the parent’s body grows out as a bud which then detaches and becomes a new organism. Hydra and yeast reproduce by budding.
Q 22 – What is the germination of seed?
When the seed gets the right conditions the embryo within it starts growing to form the shoot and the root. When the embryo emerges out of the seed to form a new seedling it is called the germination of seed.
Q 23 – What is ovulation?
The ovarian follicles present inside the ovaries develop into mature follicles. Usually, one mature ovarian follicle develops into a mature ovum. It pinches off from the surface of the ovary and enters the fallopian tube. This process is termed ovulation. Generally, ovulation takes place in only one ovary at a time.
Q 24 – List two functions of the ovary of the human female reproductive system.
Two functions of Ovary :
(i) To Produce female gamete/ovum.
(ii) To secrete female hormones / estrogen and Progesterone
Q 25 – Define fertilization.
The process of fusion of the male gamete with the female gamete of the same species, i.e., the sperm with the ovum is known as fertilization. After fertilization, the product obtained is the zygote, which eventually develops into a complete organism.
Q 26 – Describe asexual reproduction in amoeba.
Amoeba reproduces by the process of binary fission. During this process, the nucleus divides first, followed by the formation of a constriction in the cellular membrane of the amoeba. This gradually increases inwards and divides the cytoplasm into two parts. Finally, two daughter organisms are obtained.
Q 27 – Name the various types of asexual reproduction.
The various types of asexual reproduction are
• Fission – binary and multiple
• Budding
• Spore formation
• Regeneration
• Vegetative propagation – It is a process by which new organisms arise without the production of seeds or spores. It can occur naturally or be induced by horticulturists.
Q 28 – Explain various steps of budding in yeast.
- Budding is a form of asexual reproduction usually observed in yeast.
- During this process, a small protrusion appears on the upper portion of the body of the organism. This bulge is called a bud.
- The bud gradually grows in size and forms an individual cell.
- From this newly budded cell, another bud appears at the tip.
- This process continues and a chain of yeast cells is obtained.
Q 29 – What is syngamy?
The process of fusion of the two gametes is known as syngamy. It is the initial step in the process of fertilization.
Q 30 – Write names of female sex hormones.
Progesterone
Q 31 – Name the causative agent of the disease “Kala-azar” and its mode of asexual reproduction.
Leishmania, Binary fission.
Q 32 – Define sexual reproduction.
The type of reproduction that involves both the sexes of the species is known as sexual reproduction. This kind of reproduction requires the fertilization of the gametes of both sexes.
Q 33 – Write the full forms of IUCD, AIDS, HIV, and OC.
The full forms for the above abbreviations are as follows
IUCD – Intrauterine Contraceptive Devices
AIDS – Acquired Immuno-Deficiency Syndrome
HIV – Human Immuno Virus
OC – Oral Contraceptives.
Q 34 – Define sexually transmitted diseases and give two examples.
There are certain infectious diseases that spread by sexual contact. Such diseases are called STDs (Sexually Transmitted Diseases). In most cases, the symptoms are burning sensation on urination and
urethral discharge. Gonorrhea and Syphilis are two examples of sexually transmitted diseases. These diseases are curable.
Q 35 – What are binary and multiple fission? Name the organisms in which they occur.
Binary fission is the division of one parent cell into two identical daughter cells. It takes place in Amoeba, Paramecium, Euglena and other protozoa.
Multiple fission is the process in which one single-celled organism divides into many daughter cells within a cyst. These are released when the cyst breaks. This takes place in Plasmodium (malarial parasite).
Q 36 – What are the various methods of vegetative propagation? Discuss any one method for example.
The various types of vegetative propagation are
• Cutting
• Layering
• Grafting
• Parthenogenesis
Micro-propagation in vitro Grafting
• It is a method in which two parts of different plants are joined together in such a way that they unite and grow as one plant.
• The portion of the plant that is grafted onto another plant is known as the scion and the plant on which grafting is performed is known as the stock.
• The stock and the scion are tied in such a way that the cambium of the scion and the stock come in contact with each other.
• The stock is so chosen that it possesses qualities like disease resistance, high water-absorbing capacity, deeply penetrating roots for a firm hold, etc. The scion is so chosen that it possesses qualities like a high yield of pulp or seeds (as desired) from a single fruit, etc.
• For example citrus-root stock is used for a variety of grafts like sweet orange, lime, grape, etc.
Q 37 – What is menstruation? Why does it occur?
Menstruation is the process of breakdown and removal of the inner lining of the uterus along with the blood vessels in the form of vaginal bleeding. This happens after every 28 days if the egg is not fertilized. This takes place in human females and in some primates.
Q 38 – Define the terms unisexual and bisexual giving examples of each.
An animal or an organism, which can be differentiated as male or female.
i.e., The two sexes are present in separate individuals, then such an organism is said to be unisexual. For example, human beings, all mammals. An animal or an organism that possesses both the sexes in a single body is said to be a bisexual animal. For example, earthworms, starfish, etc.
Q 39 – What are the three advantages of vegetative propagation?
Three advantages of vegetative propagation:
(i) Plants unable to produce viable seeds can be produced by this method.
(ii) By this method, Plants can bear flowers and fruits earlier than those produced from seeds.
(iii) The characters (traits) of the parent plant can be preserved by this method.
Q 40 – What is pollination? Describe cross-pollination.
The transfer of pollen grains from another to stigma is called pollination. Pollen grains are shed from the anther and reach the stigma of either the same flower or a different flower.
Cross-pollination
The transfer of pollen grains from the anther of one flower to the stigma of another flower of the same species is termed as cross-pollination.
Q 41 – Describe double fertilization in plants.
In the case of plants, the pollen grain releases two male gametes. One fuses with the egg and forms the zygote. The other male gamete fuses with the two polar nuclei. This fusion is said to be triple fusion. Thus, inside an embryo sac, two fusions, syngamy and triple fusion, take place. This mechanism of two fusions occurring in an embryo sac is called double fertilization.
Q 42 – What are the male and the female gonads in human beings? Mention their functions.
Testes are the male gonads in human beings. Their functions are
• To produce male hormones like testosterone.
• To produce the male gamete – sperm.
Ovaries are the female gonads in human beings. Their functions are
• To produce female hormones like estrogen and progesterone.
• To produce the female gamete – ovum.
Q 43 – Mention the secondary sexual characters in human males and females.
The male secondary sexual characters are the growth of hair on the chest, near the genitals, on the face in the form of beard and moustache, development of deep hoarse voice, etc.
The female secondary sexual characters are the development of breasts and mammary glands, axial and pubic hair, etc.
Q 44 – Discuss briefly the types of reproduction.
Reproduction is a unique biological process that is essential for the continuity and propagation of species. It is a process by which new individuals of the same species are produced by parental organisms. It takes place by two methods: –
Asexual Reproduction
This method of reproduction generally involves only one parent and is observed only in lower organisms.
Fission, budding, spore formation and vegetative propagation are some of the types of asexual propagation.
Sexual Reproduction
This method of reproduction involves two parents. It requires the fusion of gametes of both the sexes of the species. Almost all animals and higher forms of plants reproduce by this method.
Q 45 – Describe the menstrual cycle.
- The commencement of menstruation at puberty is termed menarche and marks the beginning of the reproductive life of a female.
- Initially, inside the ovary, an oogonium or an ovarian follicle is developed into a mature ovum and released into the fallopian tube. This is termed as ovulation.
- After the release, the uterus and the fallopian tubes undergo changes like the thickening of the uterine wall, development of the endometrial lining, etc. to prepare the body for a probable pregnancy.
- If fertilization does not occur, then the thickened inner wall of the uterus breaks down along with its blood vessels and moves out of the vagina in the form of bleeding, called menstrual flow (menstruation).
- It lasts for about 4-7 days.
- This cycle of events taking place in the ovaries and the uterus every 28 days and marked by the menstrual flow is known as the menstrual cycle.
- In a normal healthy woman, ovulation takes place around the 14 day and menstruation occurs every 28 to 30 days.
Q 46 – What is the effect of DNA copying, which is not perfectly accurate, on the reproduction process? How does the amount of DNA remain constant though each new generation is a combination of DNA copies of two individuals?
Reproduction results in the production of offspring similar to parents in body design and form. The exact blueprints of body design is inherited in the offspring due to DNA replication. The imperfect DNA copying results in genetic variations. This can be both useful and harmful for the offspring.
The useful variations gets selected in nature and help the organism to survive in the changing environment while as harmful variation gets eliminated.
If each new generation is to be the combination of the DNA copies from two pre-existing individuals, then each new generation will end up having twice the amount of DNA that the previous generation had. In sexual reproduction, the gametes usually contain a half the number of chromosomes and same numbers present in the body cells. These haploid gametes when fuse produces a new cell with a double number of chromosomes than the gametes and the same as the body cells. In this way organisms restrict the doubling of DNA and maintain the chromosome number.
Q 47 – (a) With the help of a diagram, show asexual reproduction in Rhizopus?
(b) How this method is advantageous for Rhizopus?
Q 48 – Differentiate between menarche and menopause.
Menarche marks the beginning of the reproductive cycle of a female whereas menopause marks the end of the reproductive cycle.
• Menarche generally takes place at puberty, i.e., at the age of 12-16 years while menopause takes place around the age of 45-50 years.
• After menarche, there is an increased amount of production of female sex hormones whereas, after menopause, the secretion of female sex hormones declines and sometimes completely stops.
Q 49 – In the context of reproduction of species state the main difference between fission and fragmentation. Also give one example of each.
Fission: It is the method of asexual reproduction in unicellular forms of life. In this process, the parent organism splits to form two or more daughter cells. Example : Ameoba
A Fragmentation: It Is the process found in multicellular organisms. The filament breaks up into two or more pieces upon maturation. These pieces then grow into new individuals.
Example : Spirogyra.
Q 50 – Fertilization is possible if copulation has taken place during the middle of the menstrual cycle. Give reasons.
During copulation, a large number of sperms enter the fallopian tube. If copulation takes place during the middle of the menstrual cycle, then fertilization is possible as at this time the ovum would have entered the fallopian tube from the ovary. If copulation takes place before ovulation then fertilization is not possible.
Fertilization is marked by the absence of regular menstrual flow.