GED Science Test #8 3

Question 1

Which describes the role of ribosomes in a cell?

Accepted Answer

Synthesizing proteins from amino acids

Answer

Ribosomes are the sites of protein synthesis. They read mRNA sequences and assemble amino acids in the correct order to build proteins. Ribosomes can be free in the cytoplasm or attached to the rough ER.

Question 2

What does the term "biodiversity" refer to?

Accepted Answer

The variety of species and genetic diversity within an ecosystem

Answer

Biodiversity refers to the variety of life forms — including species diversity, genetic diversity, and ecosystem diversity. High biodiversity generally increases ecosystem stability and resilience.

Question 3

A catalyst in a chemical reaction:

Accepted Answer

Speeds up the reaction without being consumed

Answer

A catalyst lowers the activation energy of a reaction, speeding it up, but is not consumed in the process. Enzymes are biological catalysts that control metabolism in living organisms.

Question 4

The diagram shows a wave with a wavelength of 4 m and 2 complete cycles occurring per second. What is the wave's speed?

Accepted Answer

8 m/s

Answer

Wave speed = wavelength × frequency = 4 m × 2 Hz = 8 m/s. The frequency is 2 cycles per second (2 Hz), and the wavelength is 4 m.

Question 5

Which of the following human activities most directly contributes to the loss of biodiversity?

Accepted Answer

Habitat destruction and deforestation

Answer

Habitat destruction is the leading cause of biodiversity loss. When natural habitats are cleared for agriculture, development, or logging, species lose their homes and food sources, often leading to extinction.

GED Practice Test

GED Practice Test

GED Science Test #8 3