STAAR Biology Challenge

A scientist is examining an unknown cell using an electron microscope.

 

Which observed structure would indicate that the cell is MOST LIKELY prokaryotic?

• Mitochondrion

• Free-floating DNA

• Chloroplast

• Membrane-bound nucleus

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

• 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

• An environment with many transitional fossils

Tags

NGSS.HS-LS4-5

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. 

A customer makes a copy of a grocery list at home.  

The customer drives the grocery list to the grocery store. 

The customer gives the grocery list to a cashier at the store. 

The shopper picks up the items and brings them to the cashier. 

The cashier assembles the order and a shopping cart with the order is produced. 

Based on the student's model and your knowledge of the biological process, which person or object represents tRNA?

• The cashier

• The grocery list

• The shopper

• The shopping cart

Students investigate osmosis using dialysis tubing. Dialysis tubing is a semipermeable membrane that allows water molecules to pass through while preventing salt ions from passing through. The students follow this procedure:  

 

  1. Mix salt into water to make a 7.1% salt solution.

2. Add equal amounts of this saltwater solution to four small bags made of dialysis tubing.

3. Fill four beakers with different salt solutions, as shown in the image.  

4. Place each small bag into one of the four beakers.  

5. Observe changes in the size of the bags. The setup for the investigation is shown.

In which beaker will osmosis cause expansion of the dialysis tubing bag?

• Beaker 1

• Beaker 2

• Beaker 3

• Beaker 4

Answer explanation

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 plant can use.

 

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

 

• Nitrogen

• Oxygen

• Hydrogen

• Carbon

Tags

NGSS.MS-LS2-1

Which type of mutation is LEAST LIKELY to result in a frameshift mutation?

• Insertion

• Translocation

• Substitution

• Deletion

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

• Nucleic acids and carbohydrates

• Carbohydrates and lipids

• Lipids and proteins

• Proteins and nucleic acids

Tags

NGSS.MS-LS3-1

Which of these is MOST LIKELY an indication that cells may have become cancerous?

• Cells undergoing slower rates of mitosis

• Cells with few or no mutations

• Cells not responding to checkpoints in the cell cycle

• Cells with decreased rates of protein synthesis

Tags

NGSS.HS-LS3-2

Which statement BEST describe how enzymes affect the speed of a metabolic reaction?

• Enzymes increase the concentration of reactants, which increases the speed of the reaction.

• Enzymes decrease the energy needed to start a reaction, which increases the speed of the reaction.

• Enzymes replace the reactants in a chemical reaction which decreases the speed of the reaction.

• Enzymes prevent products from being converted back into reactants, which decreases the speed of the reaction.

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?

• Different genes are expressed in the different types of blood cells.

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

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

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

Tags

NGSS.HS-LS1-1

NGSS.HS-LS1-4