Organisms

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GED Science › Organisms

Questions 1 - 8
1

What is one of the primary reasons that viruses are not considered living organisms?

They do not make their own proteins

They do not have nucleic acids

They are capable of causing disease

They do not use proteins in their structures

Explanation

Viruses are considered non-living organisms for a variety of reasons. One of the main reasons is that viruses are incapable of creating their own proteins and must hijack host cell ribosomes in order to make them.

Virus structures contain both proteins and nucleic acids, but are unable to replicate their genetic material unless they infect a host cell.

2

What is one of the primary reasons that viruses are not considered living organisms?

They do not make their own proteins

They do not have nucleic acids

They are capable of causing disease

They do not use proteins in their structures

Explanation

Viruses are considered non-living organisms for a variety of reasons. One of the main reasons is that viruses are incapable of creating their own proteins and must hijack host cell ribosomes in order to make them.

Virus structures contain both proteins and nucleic acids, but are unable to replicate their genetic material unless they infect a host cell.

3

What polysaccharide is used to construct the cell walls of fungi?

Chitin

Cellulose

Peptidoglycan

Amylose

Explanation

Fungal cell walls can be differentiated from plant and bacterial cell walls in that they are made of the polysaccharide chitin. Plant cell walls use cellulose, and bacteria use peptidoglycan. Amylose is a component of starch.

4

What polysaccharide is used to construct the cell walls of fungi?

Chitin

Cellulose

Peptidoglycan

Amylose

Explanation

Fungal cell walls can be differentiated from plant and bacterial cell walls in that they are made of the polysaccharide chitin. Plant cell walls use cellulose, and bacteria use peptidoglycan. Amylose is a component of starch.

5

The pigments in chloroplasts absorb red light and reflect green light. During photosynthesis, the absorbed light is used as energy to convert carbohydrates to ATP for the plant to use.

Under what color light would a plant grow the slowest?

Green

Red

Blue

Purple

Yellow

Explanation

The plant is only able to use absorbed light during photosynthesis; reflected light cannot be used as energy, as it is simply returned back into the surroundings. Red light will make a plant grow the fastest because it is absorbed. Since green light is reflected, growing a plant in green light will result in very slow growth. The light will effectively bounce off the plant, rather than being absorbed.

6

The pigments in chloroplasts absorb red light and reflect green light. During photosynthesis, the absorbed light is used as energy to convert carbohydrates to ATP for the plant to use.

Under what color light would a plant grow the slowest?

Green

Red

Blue

Purple

Yellow

Explanation

The plant is only able to use absorbed light during photosynthesis; reflected light cannot be used as energy, as it is simply returned back into the surroundings. Red light will make a plant grow the fastest because it is absorbed. Since green light is reflected, growing a plant in green light will result in very slow growth. The light will effectively bounce off the plant, rather than being absorbed.

7

Which of the following statements about bacteria is correct?

Bacteria are considered by scientists to be alive

Bacteria lack the necessary organelles to be considered alive

All bacteria require a host organism to infect

Bacteria are neither alive nor dead

Bacteria cells have the same general structures and organelles as animal cells

Explanation

Bacteria are prokaryotic organisms and are considered alive. Bacteria can survive and reproduce independent of a host (consider a colony of bacteria cells growing in a Petri dish). Though they do not have membrane-bound organelles, like a nucleus or mitochondria, bacterial cells do have DNA and are still able to produce cellular energy.

This question confuses many properties of viruses with those of bacteria. Viruses are not generally considered alive and require a host cell in order to replicate.

8

Which of the following statements about bacteria is correct?

Bacteria are considered by scientists to be alive

Bacteria lack the necessary organelles to be considered alive

All bacteria require a host organism to infect

Bacteria are neither alive nor dead

Bacteria cells have the same general structures and organelles as animal cells

Explanation

Bacteria are prokaryotic organisms and are considered alive. Bacteria can survive and reproduce independent of a host (consider a colony of bacteria cells growing in a Petri dish). Though they do not have membrane-bound organelles, like a nucleus or mitochondria, bacterial cells do have DNA and are still able to produce cellular energy.

This question confuses many properties of viruses with those of bacteria. Viruses are not generally considered alive and require a host cell in order to replicate.