Both, autogamy and geitonogamy are prevented in:

(1) Papaya           

(2) Cucumber       

(3) Castor             

(4) Maize

A typical angiosperm anther is bilobed with each lobe having two theca i.e. dithecous. Theca is separated often by :
1. A longitudinal groove running lengthwise.
2. A longitudinal groove running breadth wise.
3. A transverse groove running breadth wise.
4. A transverse groove running lengthwise.

Four statements are given below. How many of them are correct?
(1) The anther is a tetragonal structure, with four microsporangia at corners, two in each lobe.
(2) Microsporangia develops further and becomes a pollen sacs.
(3) A typical microsporangia is surrounded by four layered wall, 3-protective and 1 nutritional.
(4) The nutritive layer is densely cytoplasmic with more than one nucleus

Options :

1. 3                         
2. 4
3. 2                         
4. 1

Which of the following statements is not correct for a pollen grain?
1. It represents a male gametophyte.
2. It is a spherical structure, about 25-50 micrometers in diameter.
3. Pollen grains are rich in nutrients.
4. In the families Rosaceae, Leguminosae and Solanaceae, pollen loses viability in 30 minutes.

In which organ the growth of pollen tube is observed, till it reaches the ovules?

A.Pollen tube

B.Style

C.Ovary

D.Stigma

Read the statements and select option representing correct statements with respect to stamen.
A. The distal end of filament is attached to thalamus.
B. A typical anther is dithecous and bisporangiate.
C. Connective is sterile vasculated tissue.
D. Microsporangia develop further and become pollen sacs.

1. A & B

2. A & C

3. B & C

4. C & D

Genetically and functionally self-pollination is cent percent ensured with seed formation even in the absence of pollinators by

(1) Bisexuality

(2) Dicliny

(3) Geitonogamy

(4) Cleistogamy

How many statement(s) is/are correct for pollen grains?
a. Parthenium is a cause of bronhial afflictions
b. Intine exhibits fascinating array of patterns and designs
c. Cytoplasm of pollen grain is s urrounded by spermoderm
d. Generative cell is present when pollens are shed in 40 percent plants.

1. One

2. Two

3. Three

4. Four

Fossilization of pollen grains is helped by

(1) Compatible protein  

(2) Sporopollenin

(3) Cellulose

(4) Pectin

Gynoecium of Michelia and Papaver is similar in being