Most accepted theory for ascent of sap is
capillary theory
root pressure theory
pulsation theory
transpiration pull
Which of the following is not the feature of gymnosperms?
parallel venation
perennial plants
distinct branches (long and short branches)
xylem with vessels
Which of the following is/ are grouped under phanerogams?
Angiosperms
Gymnosperms
Pteridophytes
Both (a) and (b)
Which of the following theory gives the latest explanation for the closure of stomata?
ABA theory
Munch Theory
Starch glucose theory
Active K+ transport theory
D.
Active K+ transport theory
As per 'Active K+ transport mechanism' accumulation of K+ ions occurs in the guard cells during the day inresponse to light. It increases the turgidity of guard cells, consequently stomata open.
During night, ions move out of the guard cells into surrounding epidermal cells consequently guard cells become flaccid and stomata close.
The trisomy for 21st chromosome is called
Down's syndrome
Turner's syndrome
Sickle cell anaemia
Klinfelter's syndrome
Which is correctly matched?
Apiculture - Honey bee
Pisciculture - Silk moth
Sericulture - Fish
Aquaculture - Mosquito