Biology S2: Unit 1 - Part 1

Which statement is correct?

• Eyes look different than a liver because the cells that make up these organs have different genes.

• As cells and tissues differentiate, they lose the genes they do not need.

• All cells have the same genes, but different genes are active in different cells.

• All cells have the same genes, and all of a cell's genes are active at the same time.

Tags

NGSS.HS-LS1-4

Which diagram shows a system in which the lac operon genes are about to be transcribed?

• Diagram A because the repressor protein is ready to transcribe the genes.

• Diagram A because the repressor protein is no longer attached to the DNA segment.

• Diagram B because the repressor protein is ready to transcribe the genes.

• Diagram B because there is no lactose present.

Tags

NGSS.HS-LS1-1

Which action must happen for transcription of the lac operon genes to take place?

• The repressor protein falls off the DNA molecule, and RNA polymerase binds to the promoter.

• The repressor protein binds to the DNA molecule, and RNA polymerase falls off.

• Lactose is removed from the system.

• The repressor protein binds to the promoter sequence.

Tags

NGSS.HS-LS1-1

Which clue would tell if the lac operon is on?

• Lactose is absent.

• The repressor protein has fallen off the molecule.

• RNA polymerase is blocked by the repressor.

• The cell membrane changes.

How is the cell in Diagram B effectively using its resources?

• RNA polymerase is transcribing the genes since lactose is present.

• Since lactose is present, the repressor protein will begin transcription.

• Since lactose is absent, the repressor protein is blocking the genes and stopping transcription.

• The cell continually produces the enzymes needed to break down lactose.

Tags

NGSS.HS-LS1-1

How do scientists construct recombinant DNA molecules?

• by using RNA from plants

• by combining the RNA of two different organisms

• by combining the proteins from two different organisms

• by combining the DNA of two different organisms

Scientists involved in biotechnology sometimes insert the DNA of one organism into a second organism.

Which phrase best explains why they do this?

• to stop the organism's gene expression

• to create new species of organisms

• to cause the second organism to produce proteins

• to make new cell membranes

Tags

NGSS.HS-LS1-1

How is the information in a DNA molecule expressed in an organism?

• through recombinant DNA

• through proteins

• through plasmids

• through RNA polymerase

Tags

NGSS.HS-LS1-1

Cells in your hair follicles produce the protein keratin, which is a primary component of hair. Cells in your liver do not produce keratin.

Why does this specialization occur?

• Hair follicle cells contain different genes from liver cells.

• Hair follicle cells do not produce DNA, but liver cells do.

• Different types of genes are activated in liver cells and hair follicle cells.

• Hair follicle cells contain recombinant DNA.

Tags

NGSS.HS-LS1-1

NGSS.HS-LS1-6

When a human embryo is developing, the embryo produces a special type of hemoglobin not found in infant, child, or adult blood.

Which statement best explains how an embryo can produce a different type of hemoglobin from an infant, child, or adult?

• The embryo has different genes from the infant, child, or adult.

• Humans have genes for the different types of hemoglobin, which are expressed at different times.

• Development and differentiation result in the loss of certain genes.

Tags

NGSS.HS-LS1-4