1.6 IB Cyclins, Cell Cycle, and Cancer

Cyclin D.....

• triggers cells to move from G₀ to G₁ and from G₁ to S phase. Phosphorylates a protein which is a tumor suppressor.

• phosphorylates a target protein which prepares DNA for replication.

• in S phase initiates DNA replication and in G₂ phase prepares two centrioles for mitosis.

• promotes the assembly of the mitotic spindle and other tasks in preparation for mitosis, but inhibits anaphase until the cyclin has been degraded.

Tags

NGSS.HS-LS1-4

Cyclin E.....

• triggers cells to move from G₀ to G₁ and from G₁ to S phase. Phosphorylates a protein which is a tumor suppressor.

• phosphorylates a target protein which prepares DNA for replication.

• in S phase initiates DNA replication and in G₂ phase prepares two centrioles for mitosis.

• promotes the assembly of the mitotic spindle and other tasks in preparation for mitosis, but inhibits anaphase until the cyclin has been degraded.

Tags

NGSS.HS-LS1-4

Cyclin A.....

• triggers cells to move from G₀ to G₁ and from G₁ to S phase. Phosphorylates a protein which is a tumor suppressor.

• phosphorylates a target protein which prepares DNA for replication.

• in S phase initiates DNA replication and in G₂ phase prepares two centrioles for mitosis.

• promotes the assembly of the mitotic spindle and other tasks in preparation for mitosis, but inhibits anaphase until the cyclin has been degraded.

Tags

NGSS.HS-LS1-4

Cyclin B.....

• triggers cells to move from G₀ to G₁ and from G₁ to S phase. Phosphorylates a protein which is a tumor suppressor.

• phosphorylates a target protein which prepares DNA for replication.

• in S phase initiates DNA replication and in G₂ phase prepares two centrioles for mitosis.

• promotes the assembly of the mitotic spindle and other tasks in preparation for mitosis, but inhibits anaphase until the cyclin has been degraded.

Tags

NGSS.HS-LS1-4

How does the concentration of cyclin change as a cell goes through the cell cycle?

• Cyclin concentration remains constant.
• Cyclin concentration increases during interphase and decreases during mitosis.
• Cyclin concentration decreases during interphase and increases during mitosis.
• Cyclin concentration is inversely related to MPF concentrations.

Tags

NGSS.HS-LS1-4

What action do CDKs perform on target proteins?

• They make allosteric changes by binding to the protein.

• They add a methyl group to the protein.

• They remove a methyl group from the protein.

• They add a phosphate group to the protein.

• They remove a phosphate group from the protein.

Tags

NGSS.HS-PS1-2

Which statement about the relationship between cyclins and CDKs is true?

• CDKs activate cyclins.

• CDKs repress cyclins.

• Cyclins activate CDKs.

• Cyclins repress CDKs.

• Cyclins and CDKs do not interact.

Tags

NGSS.HS-LS1-4

What type of biomolecule are cyclins?

• Carbohydrates

• Lipids

• Proteins

• Steroids

Tags

NGSS.HS-LS1-1

What type of enzymes are kinases?

• They add phosphate groups to other biomolecules

• They add protein groups to other biomolecules

• They add carboxyl groups to other biomolecules

• They add amino groups to other biomolecules

Tags

NGSS.HS-PS1-2

What happens to cyclins at the end of their cycle?

• They are recycled and used again

• They are degraded

• They reach a low level and remain there until they are needed, then they increase to their optimum level

• They stay at a constant level throughout the cell cycle