Biology STAAR Mini-Test [2026]

Instructions

This is a (very) shortened version of the actual STAAR test! It includes some of the different question types that may appear on the actual STAAR test. 

Answer all questions to the best of your ability, without using any notes, online resources, or other students to help you. Just try your best and give yourself a chance to see how you would actually do on these questions on the real STAAR test!

You can navigate back and forth between questions as much as you need to before your final submission. Make sure you are happy with your answers before you submit at the end of the assignment!

Required

2

Required

1

A genetic sequence undergoes a mutation. The original sequence, the mutated sequence, and a codon chart are shown.
How many amino acid changes can be identified from the mutated sequence shown? 

Record your answer in the space provided.

_______ 

Required

2

This question has two parts. First, answer Part A. Then, answer Part B.

Required

1

A population of organisms contains multiple alleles for a particular trait. A biologist assigns each allele a letter from M through T and tracks the frequency in a population. A small group of organisms travels to a new location and begins a new population.

The biologist tracked the allele frequency for the trait in the original population and the small group and recorded the data in the tables shown.

Which table shows the MOST LIKELY allele frequency of the new population?

Required

1

A student is sweating after playing basketball.

Which body systems are MOST DIRECTLY interacting as a response to maintain homeostasis?

Digestive and circulatory systems

Circulatory and nervous systems

Nervous and integumentary systems

Immune and integumentary systems

Required

1

A student makes a model of an energy pyramid by stacking cups as shown. The producers are represented by the bottom level of four cups.
How much energy will be obtained at the top of this energy pyramid if the cups representing the primary consumers have 37,000 kilojoules (kJ) of energy?

3.7 kJ

37,000 kJ

370 kJ

3,700 kJ

Required

2

In animal cells, the sodium-potassium pump moves sodium and potassium ions against a concentration gradient across the cell membrane.

What type of transport is used, AND why is this type of transport necessary?

Read the question carefully. Then enter your answers in the space below.

Required

1

A student makes a model to compare the process of transcription and translation to the process of using a grocery store that prepares orders for customers.
Based on the student’s model and your knowledge of the biological process, which person or object represents tRNA?

The grocery list

The shopping cart

The cashier

The shopper

Required

1

Which table correctly matches each type of biomolecule with its function in the cell membrane?

Required

2

A Venn diagram comparing the functions of proteins and nucleic acids is shown.

Which functions BEST complete the Venn diagram?

Select the correct answer for each box. Not all answers will be used.

A student is drawing an energy pyramid.

Examine the diagram and answer these questions:
What is the original source of all energy for the energy pyramid?
How does the amount of energy available at each level of the pyramid change from the bottom to the top?

Required

1

Microorganisms are known to be present in some food products such as yogurt. One student claims that microorganisms in food always have a negative effect on human health, while a second student disagrees. The second student claims that some microorganisms in food can have a positive effect on human health.

Which statement BEST supports the second student’s claim?

Microorganisms can aid in the absorption of nutrients from food within the digestive system.

Microorganisms reproduce too slowly to affect the immune system.

Microorganisms known to be in food are no longer living and would not affect the digestive system.

Required

1

There are different types of human blood cells. Depending on what type they are, some blood cells either carry nutrients throughout the body or destroy foreign substances in the body.

Which statement explains how genes control the differentiation of
different types of blood cells?

Specific genes in blood cells are expressed only in response to an external environmental change.

Some genes are deleted in one type of blood cell, changing the type of cell it is.

Genes found in all blood cells can change the cell to perform any function needed.

Required

1

Which two components are MOST LIKELY found in both viruses and prokaryotic cells?

Lipids and proteins

Nucleic acids and carbohydrates

Proteins and nucleic acid

Carbohydrates and lipids

Required

1

Which cellular components are the same in all living organisms?

Mitochondria

Nucleotides

DNA sequences

Nuclei

Required

1

Which statement BEST describes how genes are expressed in an organism?

Genes are turned on and off in response to the environment.

Genes are always off even when resources are available.

Genes are on until all the genes have been simultaneously expressed.

Genes are continuously turned on and off at random intervals of time.

Required

1

Which environmental condition would MOST LIKELY result in the appearance of punctuated equilibrium in the fossil record?

An environment with many transitional fossils

An environment that remains in a state of stasis

An environment that undergoes steady changes over time

An environment that experiences rapid large-scale destructive change

Required

1

The graphs show changes in allele frequencies in a population at three points in time as a drought becomes more severe.

Which statement best describes how natural selection affects alleles?

Natural selection affects allele frequencies in individuals, not in populations.

Required

1

Which statement BEST describes the roles of glucose and oxygen in photosynthesis?

Glucose releases chemical energy during photosynthesis, and oxygen is a reactant in photosynthesis.

Glucose stores chemical energy during photosynthesis, and oxygen is a reactant in photosynthesis.

Glucose stores chemical energy during photosynthesis, and oxygen is a product of photosynthesis.

Glucose releases chemical energy during photosynthesis, and oxygen is a product of photosynthesis.

Required

1

Leguminous plants, such as bean plants, share a mutualistic relationship with certain rhizobium bacteria. The plants develop harmless nodules on their roots, where the bacteria live. In return, the bacteria convert an important element from the atmosphere into a nutrient form that the plants can use.

What essential element is converted to a useable form by the rhizobium bacteria?

Record your answer in the space provided.
_______ 

Required

2

This question has two parts.

In cattle, the hornless trait is dominant to the horned trait. A farmer starts with a herd of cattle heterozygous for the horned trait and wants to keep the herd hornless. To keep the hornless trait, the farmer builds fences around the farm to prevent the cattle from mating with any horned cattle in the area.

Part A
Which statement describes what will MOST LIKELY happen to the cattle population on the farm over time?

__________

Part B
Which evidence supports your answer in Part A?

__________

Required

2

Some inherited health disorders are caused by nondisjunction. During nondisjunction, homologous chromosomes fail to separate properly during the formation of sex cells.
Based on the images, which cells MOST LIKELY show examples of nondisjunction?

Select TWO correct answers.

Required

1

The snowshoe hare often molts, or sheds its fur, during different seasons, going from a reddish brown to a white fur color.

The graphs show both the change in coat color in one population of snowshoe hares and the average snow coverage during two periods of the year.

Which statement BEST explains the data shown in the graphs?

Hare fur color changes when sexual maturity occurs in the fall months.

Hares with seasonal changes in fur color have a survival advantage and are more likely to successfully reproduce.

Required

1

The uptake of nitrogen by plants would likely be MOST affected by which occurrence?

A decrease in the burning of fossil fuels

An increase in herbivore populations

A period of seasonal rainfall

The destruction of bacteria in the soil

Required

1

The population of an invasive crab species, Callinectes sapidus, is rapidly increasing along coastal Europe. This aggressive, fast-growing omnivore reproduces quickly and is causing the extinction of many native species.

Which statement BEST describes the effect of a native species’ extinction on local ecosystem biodiversity and stability?

Extinction leads to decreases in biodiversity and decreases in stability.

Extinction leads to increases in biodiversity and decreases in stability.

Extinction leads to increases in biodiversity and increases in stability.

Extinction leads to decreases in biodiversity and increases in stability

This is the end of the practice test! Make sure you have finalized all of your answers before you submit this assignment. 

After you submit the assignment, you will be able to see whether or not you got the answers correct for each question, except for the short constructed response (free response) questions that can't be auto-graded. 

DO NOT CLOSE THIS TAB AFTER YOU SUBMIT! You will need to keep this tab open while you complete the reflection assignment, as it will require you to look back at your responses.

Biology STAAR Mini-Test [2026]

This question has two parts. First, answer Part A. Then, answer Part B.

A student is sweating after playing basketball.Which body systems are MOST DIRECTLY interacting as a response to maintain homeostasis?

A student makes a model of an energy pyramid by stacking cups as shown. The producers are represented by the bottom level of four cups.How much energy will be obtained at the top of this energy pyramid if the cups representing the primary consumers have 37,000 kilojoules (kJ) of energy?

In animal cells, the sodium-potassium pump moves sodium and potassium ions against a concentration gradient across the cell membrane.What type of transport is used, AND why is this type of transport necessary?Read the question carefully. Then enter your answers in the space below.

A student makes a model to compare the process of transcription and translation to the process of using a grocery store that prepares orders for customers.Based on the student’s model and your knowledge of the biological process, which person or object represents tRNA?

Which table correctly matches each type of biomolecule with its function in the cell membrane?

A student is drawing an energy pyramid.Examine the diagram and answer these questions:What is the original source of all energy for the energy pyramid?How does the amount of energy available at each level of the pyramid change from the bottom to the top?

There are different types of human blood cells. Depending on what type they are, some blood cells either carry nutrients throughout the body or destroy foreign substances in the body.Which statement explains how genes control the differentiation ofdifferent types of blood cells?

Which two components are MOST LIKELY found in both viruses and prokaryotic cells?

Which cellular components are the same in all living organisms?

Which statement BEST describes how genes are expressed in an organism?

Which environmental condition would MOST LIKELY result in the appearance of punctuated equilibrium in the fossil record?

The graphs show changes in allele frequencies in a population at three points in time as a drought becomes more severe.Which statement best describes how natural selection affects alleles?

Which statement BEST describes the roles of glucose and oxygen in photosynthesis?

Some inherited health disorders are caused by nondisjunction. During nondisjunction, homologous chromosomes fail to separate properly during the formation of sex cells.Based on the images, which cells MOST LIKELY show examples of nondisjunction?Select TWO correct answers.

The uptake of nitrogen by plants would likely be MOST affected by which occurrence?

This is the end of the practice test! Make sure you have finalized all of your answers before you submit this assignment.

DO NOT CLOSE THIS TAB AFTER YOU SUBMIT! You will need to keep this tab open while you complete the reflection assignment, as it will require you to look back at your responses.

A student studying mitosis captures an image of cells from an onion root tip with a camera mounted on a microscope.Which events occur after the phase circled in the student’s image?Select TWO correct answers.

This question has two parts. First, answer Part A. Then, answer Part B.

A student is sweating after playing basketball.Which body systems are MOST DIRECTLY interacting as a response to maintain homeostasis?

A student makes a model of an energy pyramid by stacking cups as shown. The producers are represented by the bottom level of four cups.How much energy will be obtained at the top of this energy pyramid if the cups representing the primary consumers have 37,000 kilojoules (kJ) of energy?

In animal cells, the sodium-potassium pump moves sodium and potassium ions against a concentration gradient across the cell membrane.What type of transport is used, AND why is this type of transport necessary?Read the question carefully. Then enter your answers in the space below.

A student makes a model to compare the process of transcription and translation to the process of using a grocery store that prepares orders for customers.Based on the student’s model and your knowledge of the biological process, which person or object represents tRNA?

Which table correctly matches each type of biomolecule with its function in the cell membrane?

A student is drawing an energy pyramid.Examine the diagram and answer these questions:What is the original source of all energy for the energy pyramid?How does the amount of energy available at each level of the pyramid change from the bottom to the top?

There are different types of human blood cells. Depending on what type they are, some blood cells either carry nutrients throughout the body or destroy foreign substances in the body.Which statement explains how genes control the differentiation ofdifferent types of blood cells?

Which two components are MOST LIKELY found in both viruses and prokaryotic cells?

Which cellular components are the same in all living organisms?

Which statement BEST describes how genes are expressed in an organism?

Which environmental condition would MOST LIKELY result in the appearance of punctuated equilibrium in the fossil record?

The graphs show changes in allele frequencies in a population at three points in time as a drought becomes more severe.Which statement best describes how natural selection affects alleles?

Which statement BEST describes the roles of glucose and oxygen in photosynthesis?

Some inherited health disorders are caused by nondisjunction. During nondisjunction, homologous chromosomes fail to separate properly during the formation of sex cells.Based on the images, which cells MOST LIKELY show examples of nondisjunction?Select TWO correct answers.

The uptake of nitrogen by plants would likely be MOST affected by which occurrence?

This is the end of the practice test! Make sure you have finalized all of your answers before you submit this assignment.

DO NOT CLOSE THIS TAB AFTER YOU SUBMIT! You will need to keep this tab open while you complete the reflection assignment, as it will require you to look back at your responses.

A student is sweating after playing basketball.

Which body systems are MOST DIRECTLY interacting as a response to maintain homeostasis?

A student makes a model of an energy pyramid by stacking cups as shown. The producers are represented by the bottom level of four cups.
How much energy will be obtained at the top of this energy pyramid if the cups representing the primary consumers have 37,000 kilojoules (kJ) of energy?

In animal cells, the sodium-potassium pump moves sodium and potassium ions against a concentration gradient across the cell membrane.

What type of transport is used, AND why is this type of transport necessary?

Read the question carefully. Then enter your answers in the space below.

A student makes a model to compare the process of transcription and translation to the process of using a grocery store that prepares orders for customers.
Based on the student’s model and your knowledge of the biological process, which person or object represents tRNA?

A student is drawing an energy pyramid.

Examine the diagram and answer these questions:
What is the original source of all energy for the energy pyramid?
How does the amount of energy available at each level of the pyramid change from the bottom to the top?

There are different types of human blood cells. Depending on what type they are, some blood cells either carry nutrients throughout the body or destroy foreign substances in the body.

Which statement explains how genes control the differentiation of
different types of blood cells?

The graphs show changes in allele frequencies in a population at three points in time as a drought becomes more severe.

Which statement best describes how natural selection affects alleles?

Some inherited health disorders are caused by nondisjunction. During nondisjunction, homologous chromosomes fail to separate properly during the formation of sex cells.
Based on the images, which cells MOST LIKELY show examples of nondisjunction?

Select TWO correct answers.

A student studying mitosis captures an image of cells from an onion root tip with a camera mounted on a microscope.
Which events occur after the phase circled in the student’s image?

Select TWO correct answers.

A student is sweating after playing basketball.

Which body systems are MOST DIRECTLY interacting as a response to maintain homeostasis?

A student makes a model of an energy pyramid by stacking cups as shown. The producers are represented by the bottom level of four cups.
How much energy will be obtained at the top of this energy pyramid if the cups representing the primary consumers have 37,000 kilojoules (kJ) of energy?

In animal cells, the sodium-potassium pump moves sodium and potassium ions against a concentration gradient across the cell membrane.

What type of transport is used, AND why is this type of transport necessary?

Read the question carefully. Then enter your answers in the space below.

A student makes a model to compare the process of transcription and translation to the process of using a grocery store that prepares orders for customers.
Based on the student’s model and your knowledge of the biological process, which person or object represents tRNA?

A student is drawing an energy pyramid.

Examine the diagram and answer these questions:
What is the original source of all energy for the energy pyramid?
How does the amount of energy available at each level of the pyramid change from the bottom to the top?

There are different types of human blood cells. Depending on what type they are, some blood cells either carry nutrients throughout the body or destroy foreign substances in the body.

Which statement explains how genes control the differentiation of
different types of blood cells?

The graphs show changes in allele frequencies in a population at three points in time as a drought becomes more severe.

Which statement best describes how natural selection affects alleles?

Some inherited health disorders are caused by nondisjunction. During nondisjunction, homologous chromosomes fail to separate properly during the formation of sex cells.
Based on the images, which cells MOST LIKELY show examples of nondisjunction?

Select TWO correct answers.