Ecology (18%)
11 Questions
Test Prep Questions
6th Grade
6th Grade (5b Ecology)
Students know matter is transferred over time from one organism to others in the
food web and between organisms and the physical environment. (pg. 97 Science
Framework)
Summary: Energy and matter are transferred from one organism to another organism
through consumption. Plants are eaten by primary consumers (herbivores); most
herbivores are eaten by secondary consumers (carnivores); and those consumers are eaten
by tertiary consumers (often top level predators). Energy is transferred from organisms
to the physical environment through heat loss. Carbon is returned to the physical
environment as airborne carbon dioxide through the respiration of organisms. Water is
also cycled.
6th Grade (5c Ecology)
Students know populations of organisms can be categorized by the functions they
serve in an ecosystem. (pg. 98 Science Framework)
Summary: Organisms in a population may be categorized by whether they are producers
of chemical energy from solar energy or consumers of chemical energy and, if they are
consumers, whether they are predators, scavengers, or decomposers.
6th Grade (5e Ecology)
Students know the number and types of organisms an ecosystem can support
depends on the resources available and on abiotic factors, such as quantities of light
and water, a range of temperatures and soil composition. (pg. 99 Science
Framework)
Summary: There is a greater variety of types of organisms in temperature or tropical
environments than in deserts or polar tundra. The number of organisms supported by an
ecosystem also varies from season to season. The richness of plant growth depends on
abiotic factors, such as water, sunlight, moderate temperatures, temperature ranges, and
composition of the soils. To support vigorous growth, soils must contain sufficient
minerals (nitrogen, phosphorus, potassium) and humus (decomposed organic materials)
without excess acidity or alkalinity.
Biology/Life Science
Biology (6a Ecology)
Students know biodiversity is the sum total of different kinds of organisms and is
affected by alterations of habitats.
Summary: Biodiversity refers to the collective variety of living organisms in an
ecosystem. This structure is influenced by alterations in habitat, including but not limited
to climate changes, fire, flood, and invasion by organisms from another system. The
more biodiversity in an ecosystem, the greater its stability and resiliency.
Biology (6b Ecology)
Students know how to analyze changes in an ecosystem resulting from changes in
climate, human activity, introduction to nonnative species, or changes in population
size.
Summary: Analysis of change can help people to describe and understand what is
happening in a natural system and, to some extent, to control or influence that system.
Understanding different kinds of change can help to improve predictions of what will
happen next
-------------------------------------------------------------Massachusetts Released Question
A rabbit population has increased noticeably in the past ten years. Which of the
following is a reasonable hypothesis for this population growth?
A
B
C
D
Competition for food has increased among rabbits.
The rabbit’s main predator has been eliminated by human development.
Abnormal weather conditions have decreased water levels of the local ponds.
An organism that relies on similar food sources has migrated into the area.
Answer: B The rabbit’s main predator has been eliminated by human development.
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Virginia State Released Question
In this food web, which organism has the greatest number of food sources?
A snake
B hawk
C shrew
D mouse
Answer: B hawk
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Biology (6c Ecology)
Students know how fluctuations in population size in an ecosystem are determined by
the relative rates of birth, immigration, emigration, and death.
Summary: Fluctuations in the size of a population are often difficult to measure directly
but may be estimated by measuring the relative rates of birth, death, immigration, and
emigration in a population. The number of deaths and emigrations over time will
decrease a population’s size, and the number of births and immigrations over time will
increase it. Comparing rates for death and emigration with those for birth and
immigration will determine whether the population shows a net growth or a decline over
time.
-------------------------------------------------------------Virginia Released Question
Which of these could cause a decrease in the number of squirrels in a population?
A
B
C
D
An increase in cooperation with birds in the area.
An increase in the squirrel’s territory.
An increase in competition with other nut-eating animals.
An increase in the squirrel’s food supply.
Answer: C An increase in competition with other nut-eating animals.
-------------------------------------------------------------Biology (6d Ecology)
Students know how water, carbon, and nitrogen cycle between abiotic resources and
organic matter in the ecosystem and how oxygen cycles through photosynthesis and
respiration.
Summary: Living things depend on nonliving things for life. At the organism level
living things depend on natural resources, and at the molecular level, they depend on
chemical cycles. Water, carbon, nitrogen, phosphorus, and other elements are recycled
back and forth between organisms and their environments. These chemicals are
incorporated into plants (producers) by photosynthesis and nitrogen fixation and used by
animals (consumers) for food and protein synthesis. Chemical recycling occurs through
respiration, the excretion of waste products and, of course, the death of organisms.
Biology (6e Ecology)
Students know a vital part of an ecosystem is the stability of its producers and
decomposers.
Summary: An ecosystem’s producers (plants and photosynthetic microorganisms) and
decomposers (fungi and microorganisms) are primarily responsible for the productivity
and recycling of organic matter. Conditions that threaten the stability of producer and
decomposer populations in an ecosystem jeopardize the availability of energy and the
capability of matter to recycle in the rest of the biological community.
Biology (6f Ecology)
Students know at each link in a food web some energy is stored in newly made
structures but much energy is dissipated into the environment as heat. This dissipation
may be represented in an energy pyramid.
Summary: The energy pyramid illustrates how stored energy is passed from one
organism to another. At every level in a food web, an organism uses energy
metabolically to survive and grow, but much is released as heat, usually about 90%. At
every link in a food web, energy is transferred to the next level, but typically only 10% of
the energy from the previous level is passed on to the consumer.