Mortality, Natality and Dispersal

Q.

Can humans live for 200 years?

Q. If N is population density at time t, then population density at time t+1 can be written as $N_{(t+1)}$ = $N_{\left(t\right)}$ + [(A+B) - (C+D)]
Select the correct option for A, B, C and D in the above equation.

1. A is mortality and B is natality
2. B is immigration and C is natality
3. C is mortality and D is immigration
4. A is natality and D is emigration

Q.

What do you understand by the term migration?

Q. Read the following statements and choose the correct option.
Statement 1: Evolution is not a directed process in the sense of determinism
Statement 2: Evolution is a random process based on chance events in nature and chance mutation in organisms

1. Statement 1 is true but statement 2 is false
2. Statement 1 is false but statement 2 is true
3. Both statements are true
4. Both statements are false

Q. In a pond, last year there were 30 lotus plants. Through reproduction, 25 new lotus plants were added in one year while 8 plants died. The birth and death rates for the lotus population respectively are ____ and ____ individuals per lotus per year.

1. 0.83, 0.26
2. 0.26, 0.83
3. 0.25, 0.80
4. 0.80, 0.25

Q.

In a population, unrestricted reproductive capacity is called as

1. birth rate

2. fertility rate

3. carrying capacity

4. biotic potential

Q.

Define the terms: (a) fertility rate and (b) mortality rate

Q.

What factors could lead to the rise of a new species?

Q.

List the attributes that populations but not individuals posses.

Q.

The​ _____ _____ denoted $\mathrm{p}$​ is given by the formula $\mathrm{p}=\underline{}$, where $\mathrm{x}$ is the number of individuals with a specified character in a sample of $\mathrm{n}$ individuals.

Q.

When one population is harmed and the other remains unaffected, the relationship is called

1. Amensalism

2. Protocooperation

3. Parasitism

4. Predation

Q. All the members of a single species occupying a particular area is termed a ___

1. Gene pool
2. Neighbourhood
3. Population
4. Community

Q. Choose the correct options

1. Female pelvic brim is larger and wider than the male’s
2. The angle of the pubic arch is greater in the female pelvis (over 90 degrees) than in the male pelvis (less than 90 degrees).
3. The male pelvis is deeper and has a narrower pelvic outlet than the female’s.
4. All the above

Q.

Suggest any three steps which may be taken towards controlling the rapid rise in human population.

Q. Differentiate between :
Natural selection and artificial selection

Q. Natality is

1. Total number of individuals presents for unit area at a given time.
2. Increase in the number of individuals in a population under given environmental conditions.
3. Loss of individuals due to death in a population under given environmental conditions.
4. Movement of individuals into and out of population.
5. Each population has three different age groups.

Q. Two opposite forces operate in the growth and development of every population. Once of them relates to the ability to reproduce at a given rate. The force opposing it is called.

1. Morbidity
2. Fecundity
3. Biotic potential
4. Environmental resistance

Q. Which of the following statement is true for genetic drift?

1. It upsets the Hardy Weinberg Equilibrium
2. It is responsible for preserving certain genes
3. It is responsible for eliminating genes
4. It operates only in large population

Q. Natality refers to

1. Number of organisms leaving the habitat
2. Birth rate
3. Death rate
4. Number of individuals entering the habitat

Q. Natality is also known as

1. Birth rate
2. Death rate
3. Both A and B
4. None of the above

Q. Arctic tern, fly almost 30, 000 kms a year from arctic circle to antarctic circle in search of favourable temperature and food. This movement is called:

1. aestivation
2. hibernation
3. vernalisation
4. migration

Q.

If the $C{O}_2$ level increases in the blood, it favours ______

1. Both A and B.

2. Decreased availability of O₂ in tissues

3. Unloading of O₂ from the blood

4. Loading of O₂ in the blood

Q. "The population of a metro city experiences fluctuations in its population density over a period of time".

(a) When does the population in a metro city tend to increase?
(b) When does the population in metro city tend to decline?
(c) If 'N' is the population density at the time 't', write the population density at the time 't + 1'.

Q. Define life span and life expectancy.

Q.

Choose the correct statement with respect to unicellular organisms.

1. In unicellular organisms, tissues work in co-ordination to perform different functions.

2. Unicellular organisms do not require food.

3. Unicellular organisms respire and reproduce.

4. All unicellular organisms move by cilia.

Q.

Which of the following evolutionary mechanisms acts to slow down or prevent the evolution of reproductive isolation?

1. Natural selection

2. Gene flow

3. Mutation

4. Genetic drift

Q. Adaptive radiation is an example for

1. Sympatric speciation
2. Stabilizing selection
3. Directional selection
4. Diversifying selection

Q. Define Mortality.

Q.

Number of births per 1000 is

1. Growth rate

2. Conception rate

3. Reproduction rate

4. Crude birth rate

Q. If N is population density at time t, then population density at time t+1 can be written as $N_{(t+1)}$ = $N_{\left(t\right)}$ + [(A+B) - (C+D)]
Select the correct option for A, B, C and D in the above equation.

1. A is mortality and B is natality
2. B is immigration and C is natality
3. C is mortality and D is immigration
4. A is natality and D is emigration