MODEL PAPER 7 — BIOLOGY STD 12 Science — Question

What is trophoectoderm?

Write about positive agent transmission method incubation period symptoms prophylaxis and treatment of syphilis disease.

Given below is an equation describing the Species-Area relationship between species richness and area for a wide variety of taxa as angiosperm plants, birds, bats etc.
S = CA^Z
a. Give a graphical representation of the given equation showing Species-Area relationship.
b. What does S represent in the given equation?
c. What is the value of Z (regression coefficient) for frugivorous birds and mammals in the tropical forests of different continents?

Mark the odd one the following groups.
Bulbourethral gland, Prostate, Seminal vesicle, Seminiferous tubule.

Differentiate between the following:

Template strand and Coding strand.

Differentiate between vaccination and immunization. Describe the two types of vaccines with suitable examples?

Describe the development of endosperm after double fertilization in an angiosperm. Why does endosperm development precedes that of zygote?

(i) Write the name of the agent that causes typhoid (intermittent fever) in humans.
(ii) Write the name of the test that confirms this disease.
(iii) How does its pathogen enter the human body? Write its clinical symptoms and in severe cases, name the body part that is affected by it.

Name the initial cell from which this structure has developed.

What are the Assisted Reproductive Techniques practised to help infertile couples? Describe any three techniques.