71.

The figure given below is a diagrammatic representation of the response of organisms to abiotic factors. What do A, B, and C represent respectively?

• A	B	C
  Conformer	Regulator	Partial regulator

• A	B	C
  Regulator	Partial regulator	Conformer

• A	B	C
  Partial regulator	regulator	conformer

• A	B	C
  Partial regulator	regulator	conformer

The permissible use of the technique amniocentesis is for

• detecting the sex of the unborn foetus

• artificial insemination

• transfer of embryo into the uterus of a surrogate mother

• transfer of embryo into the uterus of a surrogate mother

DNA and RNA segment tagged wit  a radioactive molecule is called

• vector

• probe

• clone

• clone

Darwin's finches are a good example of 

• industrial melanism

• connecting link

• adaptive radiation

• adaptive radiation

The signals for parturition originate from

• placenta only

• placenta as well as the fully developed foetus

• oxytocin released from the maternal pituitary

• oxytocin released from the maternal pituitary

The common nitrogen -fixer in paddy field is 

• Rhizobium

• Azopirillum

• Oscillatoria

• Oscillatoria

Which two of the following changes (1-4) usually tend to occur in the plain dwellers when they move to high altitudes (3500 m or more)?

1) Increase in red blood cell size
2) Increase in red blood cell production
3) Increase in breathing rate
4) Increase in thrombocytes count

Changes occurring are

• (2) and (3)

• (3) and (4)

• (1) and (4)

• (1) and (4)

The first movements of the foetus and appearance of hair on its head are usually observed during which month of pregnancy?

• Fourth month

• Fifth month

• Sixth month

• Sixth month

Cu ions released from copper -releasing Intra Uterine Devices (IUDs)

• make uterus unsuitable for implantation

• increase phagocytosis of sperms

• suppress sperm motility 

• suppress sperm motility 

Restriction endonucleases are enzymes which

• make cuts at specific positions within the DNA molecule

• recognize a specific nucleotide sequence for binding of DNA ligase

• restrict the action of the enzyme DNA polymerase

• restrict the action of the enzyme DNA polymerase