Which of the following best describes a colony of volvox?
Asexually reproduced cells held together in a mass, but independent of each other
Sexually reproduced cells held together in a mass, and dependent on each other
Single free-living acellular units irrespective of their parental origin
Several units of cells, held together by cytoplasmic strands and dependent on each other
Correct answer is A
No explanation has been provided for this answer.
Amoeba obtains its oxygen requirements
from oxidising food substances
from air trapped in vacuoles
through diffusion of air into its body
through an air cavity in the ectoplasm
Correct answer is C
No explanation has been provided for this answer.
Which of the following habitats cannot be used for the study of succession?
Savanna grassland
Abandoned farmland
A pond
Well cultivated land
Correct answer is D
No explanation has been provided for this answer.
Which of the following traits may not be important in marriage counselling
Sex-determination
Sickle-cell anaemia
Rhesus factor
Colour of skin
Correct answer is D
No explanation has been provided for this answer.
The passage of nerve impulse across a synapse is facilitated by the secretion of
acetylcholine
thyroxin
insulin
progesterone
Correct answer is A
No explanation has been provided for this answer.