Regents Examination in Living Environment: Questions on Standard 4, Biological Concepts, Key Idea 6 - Interdependence of Living Things

Key Idea 6—Interdependence of Living Things
Plants and animals depend on each other and their physical environment.

Animals cannot synthesize nutrients from inorganic raw materials. Therefore, animals obtain their nutrients by
combining carbon dioxide with water
consuming preformed organic compounds
hydrolyzing large quantities of simple sugars
oxidizing inorganic molecules for energy

Which organisms carry out heterotrophic nutrition?
ferns
grasses
fungi
mosses

Which activity is an example of intracellular digestion?
a grasshopper chewing blades of grass
a maple tree converting starch to sugar in its roots
an earthworm digesting proteins in its intestine
a fungus digesting dead leaves

A hydra ingests a daphnia, digests it, and later egests some materials. All these events are most closely associated with the life process known as
transport
synthesis
growth
nutrition

Some bacteria are classified as saprophytes because they are organisms that
feed on other living things
feed on dead organic matter
manufacture food by photosynthesis
contain vascular bundles

Aerobic organisms are dependent on autotrophs. One reason for this dependency is that most autotrophs provide the aerobic organisms with
oxygen
carbon dioxide
nitrogen gas
hydrogen

Of the following, the greatest amount of the Earth’s food production is thought to occur in
coastal ocean waters
desert biomes
taiga forests
tundra biomes

Most of the minerals within an ecosystem are recycled and returned to the environment by the direct activities of organisms known as
producers
secondary consumers
decomposers
primary consumers

Which type of organism is not shown in the following representation of a food chain?

herbivore
decomposer
producer
carnivore

In the food chain shown below, which organism represents a primary consumer?

grasshopper
grass
frog
snake

A lake contains minnows, mosquito larvae, sunfish, algae, and pike. Which of these organisms would probably be present in the largest number?
minnows
larvae
sunfish
algae

An abiotic factor that affects the ability of pioneer organisms such as lichens to survive is the
type of climax vegetation
species of algae
type of substratum
species of bacteria

In order to avoid predators, the clown fish hides unharmed in the stinging tentacles of the sea anemone. The clown fish attracts food to the sea anemone. This is an example of a type of relationship known as
mutualism
commensalism
predator–prey
parasitism

Which world biome has the greatest number of organisms?
tundra
tropical forest
temperate deciduous forest
marine

In a particular area, living organisms and the nonliving environment function together as
a population
a community
an ecosystem
a species

 

Key Idea 6—Interdependence of Living Things: Answers and Explanations


2 The portions of food that are usable to an animal are known as nutrients. Carbohydrates, lipids, and proteins are the organic nutrients needed by all organisms. Animals cannot synthesize their own nutrients. They must eat other organisms that contain the preformed organic nutrients.
Wrong Choices Explained:
(1) Carbon dioxide and water are inorganic compounds. These compounds are converted to nutrients by plants only. The process is called photosynthesis.
(3) Hydrolysis is the breakdown of compounds to simpler molecules through the action of enzymes in the presence of water. Glucose is a simple sugar. The hydrolyzing of glucose results in the release of energy in a cell.
(4) The use of inorganic molecules for the production of energy occurs only in certain species of bacteria. Chemosynthesis does not occur in members of the animal kingdom.
 

3 Fungi are nongreen plants. They are heterotrophs, which means that they cannot manufacture their own food. Organisms that carry out heterotrophic nutrition must take in preformed organic molecules.
Wrong Choices Explained:
(1), (2), (4) Ferns, grasses, and mosses are green plants or bryophytes. Green plants are autotrophs, which means that they manufacture their own food.
 

2 Digestion that occurs within a cell is known as intracellular digestion. Plants do not have special digestive systems. Digestion, or the conversion of starch to sugar, occurs within the individual cells of a plant, including those of the root.
Wrong Choices Explained:
(1) Grasshoppers have a digestive system. Digestion is extracellular and takes place in a digestive tube outside the body cells. Chewing a blade of grass is an example of mechanical digestion taking place in the mouth.
(3) Earthworms also have a digestive system. Proteins are digested outside the body cells in a portion of the digestive system known as the intestine.
(4) Fungi demonstrate a special form of extracellular digestion. Digestive enzymes are secreted into the external environment. The nutrients from the digested food diffuse into the cells.
 

4 Nutrition is the life process most closely associated with a hydra ingesting, digesting, and egesting a daphnia. Ingestion is the process by which food materials are taken into the body of an organism such as a hydra. Digestion is the process by which the complex food molecules within the daphnia are hydrolyzed to soluble end products. Egestion is the process by which the undigestible materials of the daphnia’s body are expelled from the body of the hydra.
Wrong Choices Explained:
(1) Transport is the life process by which soluble foods and other materials are circulated through the body of an organism such that they reach all parts of the organism’s body.
(2) Synthesis is a process by which complex materials are constructed from simpler chemical components. The processes described in the question represent hydrolysis, the opposite of synthesis.
(3) Growth is a process that involves an increase in cell number and cell size, leading to an increase in the size of the organism. The end products of digestion can be used to supply raw materials for such growth.
 

2 Saprophytes are organisms that feed on dead organic matter. Fungi and the bacteria of decay are examples of saprophytes.
Wrong Choices Explained:
(1) Heterotrophs live on or off other living organisms. A dog flea is an example of a heterotroph also known as a parasite.
(3) Autotrophs manufacture their own food by photosynthesis. Algae, mosses, and grasses are examples of autotrophs.
(4) Higher plants contain vascular bundles. These plants, called tracheophytes, include ferns, conifers, and flowering plants.
 

1 Aerobic organisms need oxygen for cellular respiration. Some autotrophs are photosynthetic organisms. Oxygen is released by photosynthesis. Aerobic organisms depend on the autotrophs to release oxygen into the environment.
Wrong Choices Explained:
(2) Carbon dioxide is a waste product from the cellular respiration of aerobic organisms.
(3) Nitrogen gas makes up 78% of the atmosphere. However, the nitrogen cannot be used in the gaseous form by aerobic organisms and most autotrophs.
(4) Hydrogen does not exist as a gas on our planet. It is combined with other elements. The hydrogen needed by organisms comes mostly from water and organic compounds.
 

1 The area of greatest food production is in the region where the greatest rate of photosynthesis occurs. The area must be rich in minerals, water, gases, and light. The coastal ocean waters meet these requirements.
Wrong Choices Explained:
(2) There is very little precipitation in the desert. Water is the factor that limits plant growth.
(3) The water in the taiga is frozen part of the year.
(4) The tundra is a frozen plain. Water is frozen almost all year long on the tundra.
 

3 Bacteria of decay are decomposers that release minerals from decaying plant and animal bodies and return them to the environment.
Wrong Choices Explained:
(1) Producers are autotrophs, that is, green plants that synthesize food by photosynthesis from carbon dioxide and water in the presence of sunlight.
(2) Secondary consumers are animals that eat other animals. For example, a frog feeds on flies. Thus, a frog is a secondary consumer.
(4) Primary consumers are organisms that feed on plants only. Herbivores are primary consumers.
 

2 Decomposers are not shown in the food chain. They are organisms that live on dead things. Fungi and bacteria are decomposers.
Wrong Choices Explained:
(1) An herbivore is a primary consumer; that is, it eats vegetation. The mouse is the herbivore in the food chain.
(3) A producer is a green plant. It depends on sunlight to synthesize its own food. The grass is the producer in the food chain.
(4) A carnivore is an animal that eats the flesh of other animals. Both the snake and the hawk are carnivores.
 

1 The grasshopper is a primary consumer because it feeds on vegetation.
Wrong Choices Explained:
(2) Grass is an autotroph, that is, a producer or self-feeder. Grass is a green plant that can make its own food.
(3) A frog is a secondary consumer; it eats insects that are plant eaters.
(4) A snake is a secondary consumer; it eats animals that are primary consumers.
 

4 The organisms in the question make up a food chain. The number of organisms at each level of the food chain decreases as one moves down the chain. The pyramid of energy shown below represents this fact. The producers, which form the base of the pyramid, are the most numerous. Algae are the producers in this food chain.

Wrong Choices Explained:
(1) The minnows are carnivores. They are the secondary consumers.
(2) The larvae are herbivores. They are primary consumers.
(3) The sunfish are tertiary consumers and occupy the top level of the pyramid. The organisms at the top of the pyramid are the least numerous.
3 A substratum is the surface on which organisms grow. Lichens grow on rocks. Rocks are nonliving. The nonliving parts of the environment make up the abiotic factors.
Wrong Choices Explained:
(1) Climax vegetation is the type of vegetation that occupies an area in its final stage of succession. Plants make up the biotic, or living, environment.
(2) Algae are living organisms. They are part of the biotic (living) environment.
(4) Bacteria also make up the biotic environment.
1 A relationship between two organisms in which both benefit from the association is known as mutualism. The clown fish is protected by the sea anemone. The sea anemone is sessile. The clown fish draws food to the sea anemone.
Wrong Choices Explained:
(2) Commensalism is a relationship between two organisms in which one organism is benefited by the association. The second organism is neither harmed nor benefited by the association. Barnacles attached to a whale are an example of a commensal relationship.
(3) A predator is a carnivore that hunts, kills, and eats its prey. The prey is the hunted organism. A predator-prey relationship is important in controlling the population of both.
(4) Parasitism is a relationship between two organisms in which one organism is benefited by the association whereas the second organism is harmed by the association. The parasitized organism is called the host.
 

4 A biome is a large area dominated by one major type of vegetation and one type of climate. The marine biome has the greatest number of organisms.
Wrong Choices Explained:
(1) The tundra is a region where the ground is frozen all year long. Mosses and lichens are the dominant vegetation.
(2) The tropical rain forest is dominated by broadleaf plants. The region is always warm, and the rainfall is abundant and continuous.
(3) The temperate deciduous forest is made up of trees that shed their leaves once a year. The winters are cold, and the summers are warm. The rainfall is distributed throughout the year.
 

3 An ecosystem is an area in which communities of living organisms interact with the nonliving environment.
Wrong Choices Explained:
(1) A population is all the organisms of a particular species living in a given area.
(2) A community is made up of populations of different species that interact with each other.
(4) A species is a group of organisms whose members are able to interbreed with each other. The offspring resulting from the matings are fertile and can reproduce.