STD 12 - 4. principal of inheritance and variation — NEET STD 11 Science — Question

The ductless glands

Assertion: In mammals, complex respiratory system has developed.
Reason: Mammalian skin is impermeable to gases

Choose the correctly matched pair.

Which of the following statements are correct according to theory of Oparin and Haldane about origin of life ?
(i) First form of life could have come from pre- existing, non-living organic molecules (e.g., RNA, protein, etc.) and that formation of life was preceded by chemical evolution.
(ii) Formation of diverse organic molecules from inorganic constituents.
(iii) Life originated in water by condensation of inorganic substance.
(iv) The conditions on earth were - high temperature, volcanic storms, reducing atmosphere containing CH₄ NH₃ etc.
(v) The past atmosphere of earth was oxidizing.
(vi) Diversity was always the same since creation and will be the same in future also.

Azolla possesses symbiotic association with

Essential ion far blood clotting

Gametes produced by a homozygous individual is/are of .... types

How many statements are correct for fertilization?
i. The motile sperms swim rapidly enter into the uterus after insemination and finally reach fallopian tube.
ii. Fertilisation only occurs at the ampullary- isthmic junction.
iii. During fertilisation, a sperm comes in contact with the zona pellucida layer of the ovum and induces changes in the membrane that block the entry of additional sperms.
iv. The secretions of the acrosome help the sperm enter into the cytoplasm of the ovum and induce the completion of the meiotic division of the secondary oocyte.
v. Scientifically it is correct to say that the sex of the body is determined by the father and not by the mother.

Tube feet are the characteristic structures of

Which is a wrong relation