What is true about the isolated small tribal populations?
There is a decline in population as boys marry girls only from their own tribe
Hereditary diseases like colour blindness do not spread in the isolated population
Wrestlers who develop strong body muscles in their lifetime pass this character on their progeny
Wrestlers who develop strong body muscles in their lifetime pass this character on their progeny
B.
Hereditary diseases like colour blindness do not spread in the isolated population
The population can be defined as a group or assemblage of organisms of the same species that live at a given time in a particular area. In human beings a dominant X- linked gene is necessary for the formation of colour sensitive cells the cones, in the retina of the eye. The recessive form of this gene is incapable of producing the colour sensitive cones and homozygous recessive female and hemizygous recessive males are unable to distinguish between these two colours. As the isolated population do not have any hereditary diseases like colour blindness, so they do not spread accordingly.
According to the theory of inheritance of acquired characters of Lamarck the Wrestlers, who develop strong body muscles in their lifetime, must pass this character onto their progeny, but this is not found true.
Gene pool is defined as the sum total of genes present in a Mendelian population. The study of gene pools tells us the total number of genes, their kinds and variety present in the population.
Consider the following statements concerning food chains
A) removal of 80% tigers from an area resulted in greatly increased growth of vegetation
B) removal of most of the carnivores resulted in an increased population of deers
C) length of food chains is generally limited to 3-4 trophic levels due to energy loss
D) the length of food chains may vary from 2 to 8 trophic level
Which two of the above statements are correct?
B and C
C and D
A and D
A and D
Geometric representation of age structure is a characteristic of
Biotic community
Population
Landscape
Landscape
The table below gives the populations (in thousand) of ten species (A-J) in four areas (a-d) consisting of the number of habitats given within brackets aginst each. study the table and answer the question which follows:
|
Area and number of habitats
|
Species and their populations (in thousands) in the area |
|||||||||
|
A |
B |
C |
D |
E |
F |
G |
H |
I |
J |
|
|
a(11) b(11) c(13) d(12) |
23 |
1.2 |
0.52 |
6.0 |
- |
3.1 |
1.1 |
9.0 |
- |
10.3 |
|
10.2 |
- |
0.62 |
- |
1.5 |
3.0 |
- |
8.2 |
1.1 |
11.2 |
|
|
11.3 |
0.9 |
0.48 |
2.4 |
1.4 |
4.2 |
0.8 |
8.4 |
2.2 |
4.1 |
|
|
3.2 |
10.2 |
11.1 |
4.8 |
0.4 |
3.3 |
0.8 |
7.3 |
11.3 |
2.1 |
|
Which area out of a to d shows maximum species diversity?
b
c
d
d
The population of an insect species shows an explosive increase in numbers during rainy season followed by its disappearance at the end of the season. What does this show?
S-shaped or sigmoid growth of this insect
The food plants mature and die at the end of the rainy season
Its population growth curve is of J-type
Its population growth curve is of J-type
