Biology STAAR 2021

Front

What is a common property of all living cells?

Back

All living cells contain DNA composed of adenine, thymine, guanine, and cytosine.

Front

What is the significance of DNA replication before cell division?

Back

DNA replication allows for genetic variation in the resulting cells.

Front

Which organism in a food web can occupy multiple trophic levels?

Back

The Loggerhead sea turtle can occupy multiple trophic levels.

Front

What role does the plasma membrane play in cellular homeostasis?

Back

The plasma membrane regulates the movement of substances in and out of the cell, maintaining a stable internal environment.

Front

What is ecological succession?

Back

Ecological succession is the gradual change in plant communities over time, leading to greater species diversity.

Front

Define 'trophic level'.

Back

A trophic level is a position in a food chain or food web, representing the flow of energy and nutrients.

Front

What is the function of mitochondria in cells?

Back

Mitochondria are responsible for carrying out aerobic cellular respiration, producing energy for the cell.

Front

What is the difference between a food chain and a food web?

Back

A food chain shows a linear sequence of energy transfer, while a food web illustrates the interconnected feeding relationships among various organisms.

Front

What is the role of producers in an ecosystem?

Back

Producers, such as plants, convert sunlight into energy through photosynthesis, forming the base of the food web.

Front

What is genetic variation and why is it important?

Back

Genetic variation refers to the differences in DNA among individuals, which is crucial for evolution and adaptation.