During development two types of B-cells will be formed:- 

I) T1 cell

II) T2 cell

Some features about T1 and T2 cells given in below;

a) Maturity achieve

b) Found in blood circulation

c) Presence of  Immunoglobulin IgM high and IgD low

d) Expressing CD21 and CD23

e) Cell expressing BAFF-R, Which bind with BAFF survival factor

Match the cell with their correct features;

#Question id: 10634

#Unit 10. Ecological Principles

Consider a population which is changing from one generation to the next as per the equation N(t) = R*N(t-1), where N(t) represents the size of the population at time t and R is a constant growth parameter. Under what condition is the population likely to go extinct?

#Question id: 10635

#Unit 10. Ecological Principles

Three important biological parameters – generation time, per capita growth rate (r) and clutch size are a function of the organism‟s body size. Which of the curves (a) or (b) represents the correct relation of each of the parameters to body size?

#Question id: 10636

#Unit 10. Ecological Principles

The demographic transition model depicts demographic changes from high- to low-level births and deaths in five stages

Stage 1 is characterized by total population numbers are low and the high birth rate is balanced by the high death rate.

B) Stage 2 is characterized by high population growth rate is results of high birth rate however, decline death rate

C) Stage 4 is characterized by decline in the proportion of the population in the reproductive age group and these changes stabilizes population size

D) Stage 3 is characterized by falling birth rates and death rates and population growth rate is zero due to the less numbers of people in the reproductive age group

#Question id: 10637

#Unit 10. Ecological Principles

Which of the following graph represent logistic growth pattern and exponential growth respectively? 

#Question id: 10638

#Unit 10. Ecological Principles

Following some statement is given

A- Mortality rate constant over age group 

B- Greater proportional survival at older age

C. Follow type III survivorship curve

D. Follow type II survivorship curve

Which of the following above statement is correct?

#Question id: 10639

#Unit 10. Ecological Principles

The schematic below shows the relationship between survivorship with age (relative to maximum lifespan) in Species 1 (dashed line) and Species 2 (solid line). Which of the following inferences is compatible with this figure?

A) Species 1 follow type I survival ship curve

 B) Species 2 follow type III survival ship curve

 C) Species 1 show parental care of offspring

 D) Species 2 showed large size of offspring than species 1