Biology STAAR Practice

The initial steps in gene expression are modeled. Double-stranded DNA first unwinds into two strands. Which process and product are represented in the diagrams?

• Process: transcription; product: mRNA

• Process: translation; product: protein

• Process: replication; product: tRNA

• Process: recombination; product: polymerase

Tags

NGSS.MS-LS3-1

The diagram represents one way an enzyme can be inhibited. Which statement explains the effect of an inhibitor on an enzyme?

• A substrate will be able to bond with the enzyme.

• The enzyme will likely be attacked by immune cells

• The enzyme will be unable to produce more enzymes.

• A substrate will be unable to attach to the enzyme.

Tags

NGSS.MS-LS1-7

Food webs such as the one shown were first used in 1927 by the animal ecologist Charles Elton. The food web below represents the feeding relationships among organisms in an Alaskan ecosystem. An environmental change that removed which of these organisms from the ecosystem would cause the most instability in the ecosystem?

• Auklets

• Foxes

• Salmon

• Zooplankton

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-3

NGSS.MS-LS2-4

An analysis of DNA and RNA sequences can be used to classify organisms. A dendrogram, such as the one shown, is based on molecular data. It can be used to represent evolutionary relationships within a group of organisms that are hypothesized to have descended from a common ancestor. Which statement is best supported by the information in this dendrogram?

• Lesser pandas are more genetically similar to giant pandas than they are to raccoons.

• Brown bears are more genetically similar to giant pandas than they are to sun bears.

• Lesser pandas are more genetically similar to raccoons than they are to giant pandas.

• The bear species are all more genetically similar to dogs than they are to giant pandas.

Tags

NGSS.MS-LS4-2

Some students used vinegar to dissolve a way the shells of three eggs and used these eggs as models of human red blood cells. The students observed the changes in the eggs when they were placed in different solutions. Which statement best describes the role of the cell membrane in this model?

• The cell membrane is an impermeable barrier that prevents water from entering the cell.

• The cell membrane allows solutions to enter the cell, which causes the cell to shrink.

• The cell membrane allows water to enter and leave the cell.

• The cell membrane removes solutes from the environment.

Tags

NGSS.MS-LS1-2

What is this an example of?

• vestigial structures

• embryology

• homologous structures

• fossil record

Tags

NGSS.MS-LS4-2

NGSS.MS-LS4-3

Viruses are considered nonliving because they need a host to reproduce.

• True

• False

A cell _______ in a hypertonic solution because water moves _______ the cell.

• shrinks; out

• shrinks; in

• swells; out

• swells; in

Which of the following follows the concentration gradient (high to low) but requires a transport protein?

• diffusion

• osmosis

• facilitated diffusion

• active transport

Name the process in the picture.

• transcription

• mitosis

• translation

• replication