Sexual Reproduction in Flowering Plants — BIOLOGY STD 12 Science — Question

An mRNA strand has a series of codon out of which three are given below:

1. AUG
2. UUU
3. UAG

1. What will their DNA codon be translated into?
2. What are the DNA codon that would have transcribed these RNA codon?

a. Give an example of viral biocontrol agent.
b. Why are they considered to be desirable when an ecologically sensitive area is being treated?

pairs of contrasting characters of:

1. Position of flowers.
2. Colours of pod.
3. Shape of pod.
4. Colour of seed, that were selected in pea plant by Mendel.

Name the important mammary gland secretions that help in resistance of the new born baby.

How is the milk production regulated by hormones in human female ? Explain.

State how has Agrobacterium tumifaciens been made a useful cloning vector to transfer DNA to plant cells.

Sperms have a tail, whereas eggs do not. Why?

Describe pollination by water in different groups of plants.

In a flowering plant, a microspore mother cell produces four male gametophytes while a megaspore mother cell forms only one female gametophyte. Explain.

Name the type of curve that characterises most population growing in favourable environment. Also define carrying capacity.