7th Period Biology STAAR Review 2025

Front

What is the concept of 'survival of the fittest'?

Back

It refers to the idea that organisms with the most beneficial traits are more likely to survive and reproduce.

Front

During which phase of the cell cycle is DNA replicated?

Back

S phase.

Front

What type of mutation is represented by the change from ATTTGAGCC to ATTGAGCC?

Back

Deletion - Frameshift.

Front

If a horse with genotype WW is crossed with a horse with genotype ww, what fraction of the offspring will have white hair?

Back

All (100%) of the offspring will have white hair.

Front

What does DNA replication result in?

Back

Two DNA molecules, each with one new strand and one original strand.

Front

Define 'mutation'.

Back

A mutation is a change in the DNA sequence that can lead to changes in traits.

Front

What is the role of DNA in living organisms?

Back

DNA carries genetic information essential for the growth, development, and reproduction of organisms.

Front

Explain the difference between genotype and phenotype.

Back

Genotype refers to the genetic makeup of an organism, while phenotype refers to the observable traits.

Front

What is a frameshift mutation?

Back

A frameshift mutation occurs when nucleotides are inserted or deleted from the DNA sequence, altering the reading frame.

Front

What is the significance of the S phase in the cell cycle?

Back

The S phase is crucial for DNA replication, ensuring that each daughter cell receives an identical set of chromosomes.