231139
A biologist studied the population of rats in a bam. He found that the average natality was 250 average mortality 240 , immigration 20 and emigration 30. The net increase in population is
1 Zero
2 10
3 15
4 05
Explanation:
In community the net increases in population$\mathrm{N}=$ (Birth Rate + Immigration) - (Death Rate + Emigration) In this question- Natality or birth rate $=250$ Mortality or death rate $=240$ Immigration $=20$ Emigration $=30$ Net Increase in population $(\mathrm{N})=(\mathrm{B}+\mathrm{I})-(\mathrm{D}+\mathrm{E})$ $\begin{aligned} & \mathrm{N}=(250+20)-(240+30) \\ & \mathrm{N}=0 \end{aligned}$ There for no change in population.
NEET-2013
Organisms and Populations
231141
Choose the correct sequence of stages of growth curve for Bacteria
1 Lag, Log, stationary, Decline phase
2 Lag, Log, Stationary phase
3 Stationary, Lag, Log, Decline phase
4 Decline, Lag, Log phase
Explanation:
When microbes are grown in a closed system or batch culture, the resulting growth curve has usually four phase- 1.Lag phase 2. Log phase 3.Stationary phase 4. Decline phase Time-dependent size of a growing bacterial cell population is commonly represented in log-scale against time, in which case, the lag and the exponential phase form a J-shaped curve.
AIPMT-2002
Organisms and Populations
231143
In an experiment freshly hatched larvae of an insect (Khapra beetle) were reared on a basal diet (complete diet without cholesterol) with increasing amounts of cholesterol. Results obtained are shown in the graph given in the table : The graph indicates that
1 cholesterol is an essential dietary requirement of khapra beetle
2 growth of khapra beetle is directly proportional to cholesterol concentration
3 cholesterol concentration of $2 \mu \mathrm{g} / \mathrm{g}$ diet is the optimum level
4 growth of khapra beetle is inhibited when cholesterol concentration exceeds $5 \mu \mathrm{g} / \mathrm{g}$ diet.
Explanation:
Cholesterol is an essential dietary requirement of kapra beetle. Here, the graph shown is the sigmoidal curve. This means that the growth curve is in a normal pattern. It consist of three phases- (i) Lag phase (ii) Log phase (3) Stationary phase. Initially, there was the lag phase, where it adjusted to the environment of cholesterol and then it entered log phase where Khapra beetlegrew rapidly followed by the stationary phase. Thus, it means that cholesterol essential dietary requirement for Khapra beetle.
AIIMS-2005
Organisms and Populations
231146 Select the correct option w.r.t. Age pyramids.
1 A - Expanding, $\mathrm{B}$ - stable, $\mathrm{C}$ - Declining
2 A - stable, $\mathrm{B}$ - Expanding, $\mathrm{C}$ - Declining
3 A - stable, $\mathrm{B}$ - Declining, $\mathrm{C}$ - Expanding
4 A - Declining, B - stable, C - Expanding
Explanation:
Expanding age pyramid- These types of pyramids have a much larger population of prereproductive and reproductive age groups and a population of post reproductive age groups is very less compared to pre-reproductive and reproductive age groups. - Stable age pyramids - Stable age pyramids are those that show a some what equal proportion of the population in each age group. The population is stable. - Declining age pyramid - A pyramid with a narrow base is also known as the declining age pyramid. It represents low fertility, low death rate, high life expectancy and increased ageing the population.
231139
A biologist studied the population of rats in a bam. He found that the average natality was 250 average mortality 240 , immigration 20 and emigration 30. The net increase in population is
1 Zero
2 10
3 15
4 05
Explanation:
In community the net increases in population$\mathrm{N}=$ (Birth Rate + Immigration) - (Death Rate + Emigration) In this question- Natality or birth rate $=250$ Mortality or death rate $=240$ Immigration $=20$ Emigration $=30$ Net Increase in population $(\mathrm{N})=(\mathrm{B}+\mathrm{I})-(\mathrm{D}+\mathrm{E})$ $\begin{aligned} & \mathrm{N}=(250+20)-(240+30) \\ & \mathrm{N}=0 \end{aligned}$ There for no change in population.
NEET-2013
Organisms and Populations
231141
Choose the correct sequence of stages of growth curve for Bacteria
1 Lag, Log, stationary, Decline phase
2 Lag, Log, Stationary phase
3 Stationary, Lag, Log, Decline phase
4 Decline, Lag, Log phase
Explanation:
When microbes are grown in a closed system or batch culture, the resulting growth curve has usually four phase- 1.Lag phase 2. Log phase 3.Stationary phase 4. Decline phase Time-dependent size of a growing bacterial cell population is commonly represented in log-scale against time, in which case, the lag and the exponential phase form a J-shaped curve.
AIPMT-2002
Organisms and Populations
231143
In an experiment freshly hatched larvae of an insect (Khapra beetle) were reared on a basal diet (complete diet without cholesterol) with increasing amounts of cholesterol. Results obtained are shown in the graph given in the table : The graph indicates that
1 cholesterol is an essential dietary requirement of khapra beetle
2 growth of khapra beetle is directly proportional to cholesterol concentration
3 cholesterol concentration of $2 \mu \mathrm{g} / \mathrm{g}$ diet is the optimum level
4 growth of khapra beetle is inhibited when cholesterol concentration exceeds $5 \mu \mathrm{g} / \mathrm{g}$ diet.
Explanation:
Cholesterol is an essential dietary requirement of kapra beetle. Here, the graph shown is the sigmoidal curve. This means that the growth curve is in a normal pattern. It consist of three phases- (i) Lag phase (ii) Log phase (3) Stationary phase. Initially, there was the lag phase, where it adjusted to the environment of cholesterol and then it entered log phase where Khapra beetlegrew rapidly followed by the stationary phase. Thus, it means that cholesterol essential dietary requirement for Khapra beetle.
AIIMS-2005
Organisms and Populations
231146 Select the correct option w.r.t. Age pyramids.
1 A - Expanding, $\mathrm{B}$ - stable, $\mathrm{C}$ - Declining
2 A - stable, $\mathrm{B}$ - Expanding, $\mathrm{C}$ - Declining
3 A - stable, $\mathrm{B}$ - Declining, $\mathrm{C}$ - Expanding
4 A - Declining, B - stable, C - Expanding
Explanation:
Expanding age pyramid- These types of pyramids have a much larger population of prereproductive and reproductive age groups and a population of post reproductive age groups is very less compared to pre-reproductive and reproductive age groups. - Stable age pyramids - Stable age pyramids are those that show a some what equal proportion of the population in each age group. The population is stable. - Declining age pyramid - A pyramid with a narrow base is also known as the declining age pyramid. It represents low fertility, low death rate, high life expectancy and increased ageing the population.
231139
A biologist studied the population of rats in a bam. He found that the average natality was 250 average mortality 240 , immigration 20 and emigration 30. The net increase in population is
1 Zero
2 10
3 15
4 05
Explanation:
In community the net increases in population$\mathrm{N}=$ (Birth Rate + Immigration) - (Death Rate + Emigration) In this question- Natality or birth rate $=250$ Mortality or death rate $=240$ Immigration $=20$ Emigration $=30$ Net Increase in population $(\mathrm{N})=(\mathrm{B}+\mathrm{I})-(\mathrm{D}+\mathrm{E})$ $\begin{aligned} & \mathrm{N}=(250+20)-(240+30) \\ & \mathrm{N}=0 \end{aligned}$ There for no change in population.
NEET-2013
Organisms and Populations
231141
Choose the correct sequence of stages of growth curve for Bacteria
1 Lag, Log, stationary, Decline phase
2 Lag, Log, Stationary phase
3 Stationary, Lag, Log, Decline phase
4 Decline, Lag, Log phase
Explanation:
When microbes are grown in a closed system or batch culture, the resulting growth curve has usually four phase- 1.Lag phase 2. Log phase 3.Stationary phase 4. Decline phase Time-dependent size of a growing bacterial cell population is commonly represented in log-scale against time, in which case, the lag and the exponential phase form a J-shaped curve.
AIPMT-2002
Organisms and Populations
231143
In an experiment freshly hatched larvae of an insect (Khapra beetle) were reared on a basal diet (complete diet without cholesterol) with increasing amounts of cholesterol. Results obtained are shown in the graph given in the table : The graph indicates that
1 cholesterol is an essential dietary requirement of khapra beetle
2 growth of khapra beetle is directly proportional to cholesterol concentration
3 cholesterol concentration of $2 \mu \mathrm{g} / \mathrm{g}$ diet is the optimum level
4 growth of khapra beetle is inhibited when cholesterol concentration exceeds $5 \mu \mathrm{g} / \mathrm{g}$ diet.
Explanation:
Cholesterol is an essential dietary requirement of kapra beetle. Here, the graph shown is the sigmoidal curve. This means that the growth curve is in a normal pattern. It consist of three phases- (i) Lag phase (ii) Log phase (3) Stationary phase. Initially, there was the lag phase, where it adjusted to the environment of cholesterol and then it entered log phase where Khapra beetlegrew rapidly followed by the stationary phase. Thus, it means that cholesterol essential dietary requirement for Khapra beetle.
AIIMS-2005
Organisms and Populations
231146 Select the correct option w.r.t. Age pyramids.
1 A - Expanding, $\mathrm{B}$ - stable, $\mathrm{C}$ - Declining
2 A - stable, $\mathrm{B}$ - Expanding, $\mathrm{C}$ - Declining
3 A - stable, $\mathrm{B}$ - Declining, $\mathrm{C}$ - Expanding
4 A - Declining, B - stable, C - Expanding
Explanation:
Expanding age pyramid- These types of pyramids have a much larger population of prereproductive and reproductive age groups and a population of post reproductive age groups is very less compared to pre-reproductive and reproductive age groups. - Stable age pyramids - Stable age pyramids are those that show a some what equal proportion of the population in each age group. The population is stable. - Declining age pyramid - A pyramid with a narrow base is also known as the declining age pyramid. It represents low fertility, low death rate, high life expectancy and increased ageing the population.
231139
A biologist studied the population of rats in a bam. He found that the average natality was 250 average mortality 240 , immigration 20 and emigration 30. The net increase in population is
1 Zero
2 10
3 15
4 05
Explanation:
In community the net increases in population$\mathrm{N}=$ (Birth Rate + Immigration) - (Death Rate + Emigration) In this question- Natality or birth rate $=250$ Mortality or death rate $=240$ Immigration $=20$ Emigration $=30$ Net Increase in population $(\mathrm{N})=(\mathrm{B}+\mathrm{I})-(\mathrm{D}+\mathrm{E})$ $\begin{aligned} & \mathrm{N}=(250+20)-(240+30) \\ & \mathrm{N}=0 \end{aligned}$ There for no change in population.
NEET-2013
Organisms and Populations
231141
Choose the correct sequence of stages of growth curve for Bacteria
1 Lag, Log, stationary, Decline phase
2 Lag, Log, Stationary phase
3 Stationary, Lag, Log, Decline phase
4 Decline, Lag, Log phase
Explanation:
When microbes are grown in a closed system or batch culture, the resulting growth curve has usually four phase- 1.Lag phase 2. Log phase 3.Stationary phase 4. Decline phase Time-dependent size of a growing bacterial cell population is commonly represented in log-scale against time, in which case, the lag and the exponential phase form a J-shaped curve.
AIPMT-2002
Organisms and Populations
231143
In an experiment freshly hatched larvae of an insect (Khapra beetle) were reared on a basal diet (complete diet without cholesterol) with increasing amounts of cholesterol. Results obtained are shown in the graph given in the table : The graph indicates that
1 cholesterol is an essential dietary requirement of khapra beetle
2 growth of khapra beetle is directly proportional to cholesterol concentration
3 cholesterol concentration of $2 \mu \mathrm{g} / \mathrm{g}$ diet is the optimum level
4 growth of khapra beetle is inhibited when cholesterol concentration exceeds $5 \mu \mathrm{g} / \mathrm{g}$ diet.
Explanation:
Cholesterol is an essential dietary requirement of kapra beetle. Here, the graph shown is the sigmoidal curve. This means that the growth curve is in a normal pattern. It consist of three phases- (i) Lag phase (ii) Log phase (3) Stationary phase. Initially, there was the lag phase, where it adjusted to the environment of cholesterol and then it entered log phase where Khapra beetlegrew rapidly followed by the stationary phase. Thus, it means that cholesterol essential dietary requirement for Khapra beetle.
AIIMS-2005
Organisms and Populations
231146 Select the correct option w.r.t. Age pyramids.
1 A - Expanding, $\mathrm{B}$ - stable, $\mathrm{C}$ - Declining
2 A - stable, $\mathrm{B}$ - Expanding, $\mathrm{C}$ - Declining
3 A - stable, $\mathrm{B}$ - Declining, $\mathrm{C}$ - Expanding
4 A - Declining, B - stable, C - Expanding
Explanation:
Expanding age pyramid- These types of pyramids have a much larger population of prereproductive and reproductive age groups and a population of post reproductive age groups is very less compared to pre-reproductive and reproductive age groups. - Stable age pyramids - Stable age pyramids are those that show a some what equal proportion of the population in each age group. The population is stable. - Declining age pyramid - A pyramid with a narrow base is also known as the declining age pyramid. It represents low fertility, low death rate, high life expectancy and increased ageing the population.
