Reproductive Health — BIOLOGY STD 12 Science — Question

Egrets are often seen along with grazing cattle. How do you refer to this interaction? Give a reason for this association.

A patient complains of suffering from constipation, stomach ache, stool with blood clots and excess mucous.
The physician diagnosed it as amoebiasis, after stool test.
a. Write the scientific name of the microbe identified in the stool sample.
b. How do you think, the patient must have contracted it?
c. Write your suggestions to the patient to avoid infection in future.

1. Name the ancestors of progymnosperm.
2. Name the ancestors of herbaceous and arborescent lycopod.
3. Name the ancestors of cycads.

Study the given pedigree chart and answer the questions that follow.

1. Is the trait recessive or dominant?
2. Is the trait sex linked or autosomal?
3. Give the genotypes of the parents in generation I and of their third and fourth child in generation II.

Explain how biodiversity is important for human.

Human blood group is a good example of multiple allelism and co-dominance. Justify.

Draw a transverse sectional view of an apple and label the following parts along with their technical names:

1. Edible part.
2. Encloses the embryo.
3. Forms the fruit wall.

Biodiversity plays a key role in many ecosystem services provided by nature.
(a) Present any two widely useful arguments to prove the validity of the statement.
(b) Write any one moral reason for protecting biodiversity.

What is detritus food chain?

Name the kind of organisms which constitute the pioneer community of xerarch and hydrarch succession, respectively.