Syngamy

Q. In gymnosperm, the endosperm is formed by

1. fusion of one male gamete with two polar nuclei
2. fusion of one male gamete with one polar nuclei
3. fusion of one male gamete with the egg
4. germination of a megaspore

Q. Self-incompatibility prevents pollen tube formation by pollen grains on the stigma of __________.

I. same flower
II. other flowers of the same plant
III. any plant in the same division

1. I and III
2. II and III
3. I and II
4. I, II and III

Q. Select the pairs in which both the structures belong to two different generations.
(a) Pollen and male gametes
(b) Anther and microspores
(c) Embryo sac and ovule
(d) Ovary and ovule

1. (a) and (c)
2. (b) and (c)
3. (c) and (d)
4. (a), (c) and (d)

Q. Given below are diagrams showing the different stages in the process of fertilisation of an egg in the human female reproductive tract. Study the diagrams and answer the questions.

Arrange the letters given below each diagram in a logical sequence to show the correct order in the process of fertilisation.

Q. Transfer of pollen grain from the flower of one plant to stigma of another flower of a different plant of the same species is known as:

1. Autogamy
2. Geitonogamy
3. Xenogamy
4. Dichogamy

Q. Fill in the blanks:
(c) Fertilisation is in humans (external/internal)

Q.

State whether the statements are true or false.​
The ovum contains XX chromosomes.​

Q. Match the labelled parts of the given figure with the correct option.​

	A	B	C	D	E
a	Fallopian tube	Oviduct​	Uterus ​	Cervix ​	Vagina ​
b	Oviduct​	Vas deferens ​	Ovary	Vagina ​	Cervix
c	Ovary	Oviduct	Uterus	Cervix	Vagina
d	Ovary	Fallopian tube	Uterus	Vagina	Cervix

1. d
2. e
3. b
4. a
5. c

Q. What joins embryo to placenta in mother's body?

Q. Test tube baby means a baby born when

1. the ovum is fertilised externally and thereafter implanted in the uterus
2. baby fully develops in a test tube
3. baby develops fully through tissue culture method
4. it develops naturally from a non-fertilised oocyte

Q. The diagram given below is that of a developing human foetus. Study the diagram and then answer the questions that follows.

Define the term gestation. What is the normal gestational period of the developing human embryo?

Q. The vital link that ensures continuity of species between organisms of one generation and the next is

1. zygote
2. sperm
3. pollen grain
4. egg

Q. For the proper implantation to occur, the zona pellucida layer of the zygote has to be removed. Which of the following is the most suitable site for the complete loss of zona pellucida layer?

1. Ovary
2. Fallopian tubes
3. Uterus
4. Cervix

Q. Assertion (A): In majority of angiosperms, endosperm is triploid.
Reason (R): Endosperm results from syngamy.

1. Both A & R are true
2. Both A & R are false
3. A is true, R is false
4. A is false, R is true

Q. Internal fertilization occurs

1. In female body
2. Outside female body
3. In male body
4. Outside male body

Q. The origin of embryo from either synergids or antipodal cells of the embryosac is called

1. Apospory
2. Apogamy
3. Parthenogenesis
4. Adventive embryony

Q. Name the organs which produce egg (or ova) in humans.​

Q. Internal fertilization takes place outside the female's body.

1. True
2. False

Q. When a fertilised egg E formed in the oviduct of a human female divides repeatedly to form an embryo, the embryo gets implanted in the thick and soft lining of the uterus. After this a disc-like special tissue T develops between the uterus wall and embryo through which all the requirements of the developing embryo (and foetus) are met from the mother's body.

The embryo is connected to the tissue T through a string like structure S.​

​(c) Name the string-like structure S?

Q. What is the fate of the following organs of a flower after fertilization?​
(c) Stamens

Q. The germ cell A produced by a person X is round in shape and it fuses with another germ cell B having a long tail and produced by a person Y. The fusion of A and B produces a new cell C. The cell C divides repeatedly and grows inside the organ D of person X to form E in which the body features of the unborn baby are not much developed.

E grows further to form F in which the various body features of the unborn baby (like hands, legs, head, eyes, and ears, etc.) can be identified. F grows further and ultimately forms a baby. ​

What are A, B, C, D, E and F? Out of the two persons X and Y, which one is male and which one female?

Q. What happens to the following after fertilization?
​(c) Stamen​

Q. fertilization leads to the frmation of embryo.
i)give the technical term for the development of embryo
ii)what are the events that occur during embryo development?
iii)the development of zygote depends on two factors.what are they?
iv)how will you categorise animals based on the development of zygote inside or outside the female body?
v)how does zygote in fungi and algae overcome dessication?