MCAS 2018 Biology Spring Test

Front

What are vestigial structures?

Back

Vestigial structures are remnants of organs or structures that had a function in an early ancestor but have lost most or all of their original function in a later species.

Front

Why do snakes have vestigial leg bones?

Back

Snakes have vestigial leg bones because they evolved from ancestors that had legs.

Front

What is the structure of a cell membrane?

Back

A cell membrane is composed of a double layer of phospholipids, which have a hydrophilic (phosphorus-containing) head and two hydrophobic (fatty acid) tails.

Front

What classifies a molecule as a lipid?

Back

A molecule is classified as a lipid if it is made up of fatty acids.

Front

What is a Punnett square used for?

Back

A Punnett square is used to predict the genetic outcomes of a cross between two organisms.

Front

What does it mean for an allele to be dominant?

Back

A dominant allele is one that expresses its trait even when only one copy is present in the genotype.

Front

What is the probability of an offspring having a specific phenotype?

Back

The probability of an offspring having a specific phenotype can be calculated using a Punnett square based on the genotypes of the parents.

Front

What factors can affect population stability?

Back

Population stability can be affected by resource availability, predation, and environmental conditions.

Front

What is methylation in genetics?

Back

Methylation is a process that adds methyl groups to DNA, often affecting gene expression.

Front

How does DNA methylation affect protein production?

Back

DNA methylation can prevent the transcription of genes, leading to reduced or absent protein production.