A. A group of individuals of the same species living together
B. A group of populations of different species living together in the same area
C A group of individuals of different species living together and their interactions with the abiotic environment
D. A group of populations of the same species living together in the same area
2. Why is sampling necessary in collecting ecological data?
A. To study the entire population of a species
B. To make accurate predictions about the future of an ecosystem
C. To avoid disturbing the natural environment
D. To make inferences about a larger population based on a smaller sample size
3. Which of the following statements is true regarding the use of the chi-squared test?
A. It is used to determine the direction of the relationship between two variables
B. It is used to determine whether the observed data differs significantly from the expected data
C. It is used to calculate the mean and standard deviation of a population
D. It is used to determine the correlation coefficient between two variables
4. The Lincoln Index helps to estimate the population size of motile organisms:
population size estimate = ${M} \times {N \over R}$
What does N represent?
A. Number of times capture is performed
B. Number of individuals caught and marked in first capture
C. Number of marked individuals recaptured
D. Total number of individuals recaptured
5. Which of the following conditions will lead to a LESS accurate population estimate using the Capture-Mark-Release-Recapture method?
A. There is emigration and immigration occurring
B. The time between samples is much shorter than the lifespan of the organism
C. There is equal mixing of the population
D. The marks applied do not alter the behaviour and predation of the organism.
6. Which of the following statements accurately describe allelopathy?
I. Allelopathy refers to the chemical interactions between plants, where secondary metabolites can inhibit or encourage growth.
II. Allelopathic compounds can be released through various means, such as leaching from plant tissues, volatilization into the air, or exudation into the soil.
III. Allelopathy is a mechanism used only by plants to reduce competition from other plant species, and establish dominance in an ecosystem.
A. I only
B. I and II only
C. I and III only
D. I, II and III
7. The introduction of myxomatosis, a viral disease with high mortality rate, into populations of European rabbits is an example of which of the following?
A. Negative feedback control of population size of rabbits due to a density-independent factor
B. Exponential growth in population size
C. Negative feedback control of population size of rabbits due to a density-dependent factor
D. Parasitism increasing the carrying capacity of the rabbit population
8. How does the mutualistic relationship between legumes and the bacteria Rhizobium benefit each organism?
A. Legumes provide Rhizobium with a source of carbohydrates, while Rhizobium fixes atmospheric nitrogen, making it available for the legume's growth.
B. Legumes provide Rhizobium with shelter and protection, while Rhizobium helps legumes absorb water and nutrients from the soil.
C. Legumes produce antimicrobial compounds that protect Rhizobium from harmful pathogens, while Rhizobium secretes growth-promoting substances that enhance legume growth.
D. Legumes provide Rhizobium with extra oxygen inside root modules for respiration, while Rhizobium assists in the breakdown of organic matter, releasing nutrients for the legume's uptake.
9&10: The following graph shows a population varying with time:
9. Which statement matches stage 1 on the population growth curve shown in the image?
A. Transitional phase with density-dependent limiting factors controlling population size
B. Carrying capacity
C. Exponential growth with few limiting factors
D. Stable populations of two populations of Paramecium grown together
10. Which of the following would be true at stage 3 of the population curve shown in the image?
A. Emigration + Mortality > Immigration + Natality
B. Immigration + Natality > Emigration + Mortality
C. Immigration + Mortality = Natality + Emigration
D. Immigration + Natality = Emigration + Mortality
