21.

Following are the two statements regarding the origin of life.

1. The earliest organisms that appeared on the earth were non-green and presumably an aerobes.
2. The first autotrophic organisms were the chemoautotrophs that never released oxygen of the above statements which on of the following options is correct?

 

• II is correct, but I is false

• Both I and II are correct

• Both I and II are false

• I is correct, but II is false

Match the following columns.

• A	B	C	D
  3	2	4	1

• A	B	C	D
  2	3	4	1

• A	B	C	D
  4	3	1	2

• A	B	C	D
  1	4	2	3

Phellogen and phellem respectively denote

• Cork and cork cambium

• Cork cambium and cork

• Secondary cortex and cork

• Cork and secondary cortex

Organ of Jacobson helps in

• Touch

• Vision

• Smell

• Hearing

Which one correctly describe reproduction and life cycle of fern?

• Spore → Gamete → Prothallus → Sporophyte

• Gamete → Spore → Prothallus → Plant

• Prothallus → Sporophyte → Gamete → Fern

• Sporangia → Spore → Prothallus → Sporophyte → Plant

The chromosome in which centromere is situated close to one end are

• Metacentric 

• Acrocentric

• Telocentric

• Sub-metacentric

Sliding filament theory can be best explained as

• When myofilaments slide pass each other actin filaments shorten while myosin filament does not shorten

• Actin-myosin filaments shorten and slide pass each other

• Actin and myosin filaments do not shorten, but rather slide pass each other

• When myofilament slide passes each other myosin filament shorten while actin filament do not shorten.

Select the correct combination of statements regarding Myasthenia gravis.

1. It is an auto-immune disorder.
2. It causes insufficient acetylcholine binding that effects muscular contraction.
3. Antibodies are developed against acetylcholine
4. Antibodies are developed against acetylcholine receptors.
5. It causes drooping of eyelids.

• I, III, IV,V

• I, III,V II

• I, II, IV, V

• II, III, IV, V

Study the following statements and select the option with correct statements.

1. Pulvinus leaf base is present in some leguminous plants
2. In Eichhornia, the petioles expand becomes green and synthesise food.
3. Opposite phyllotaxy is seen in guava.

• I and II

• I and III

• II and III

• I, II and III

Post-mitotic gap phase is characterised by all, except

• Synthesis of RNA and nucleotides

• No change in DNA content

• Synthesis of histone proteins

• Growth phase of the hell