Environmental Issues — BIOLOGY STD 12 Science — Question

1. Name the infective stage Plasmodium which Anopheles mosquito takes in along with the blood meal from an infected human.
2. Why does the infection cause fever in human?
3. Give a flow chart of the part of the life-cycle of this parasite passed in the insect.

Differentiate between in situ and ex situ approaches of conserving biodiversity.

State the functions of acrosome.

1. Why do the symptoms of malaria not appear immediately after the entry of sporozoites into the human body when bitten by female Anopheles? Explain.
2. Give the scientific name of the malarial parasite that causes malignant malaria in humans.

A red–eyed heterozygous female fruit fly is crossed with a red–eyed male. Work out all possible genotypes and phenotypes of the progeny. Comment on the pattern of inheritance of eye colour in fruit flies.

Mention the function of mitochondria in sperm.

Describe the experiment that helped demonstrate the semi-conservative mode of DNA replication.

β−galactosidase enzymes site is a preferred selectable marker in comparison to antibiotic-resistant selectable marker in biotechnology experiments. Justify.

Name and explain the techniques used in the separation and isolation of DNA fragments to be used in recombinant DNA technology.

Narrowly utilitarian arguments are put forth in support of biodiversity conservation. Explain the other two arguments that are put forth in support of the same cause.