AP Biology Unit 4 Exam Review

Antigen presenting cells work with T cells to kill invading pathogens. APC's present the antigen on their surface, and this will interact with a receptor on a T cell. What type of cell to cell signaling is this representing?

• Direct contact

• Local signaling

• Long distance signaling

• Transduction signaling

Which of the following is true of how G Protein Coupled Receptors work?

• Ligand binds to the GPCR and causes conversion of GTP to GDP

• Ligand binds to GPCR which will activate associated enzyme, and lead to amplification and cell response

• Ligand binds to the intracellular side of GPCR and activates G protein

• Ligand binds to extracellular side of GPCR and inactivates G protein

During physical activity endothelial cells will sense an increased heart rate, and will release nitric oxide. Nitric oxide acts on nearby smooth muscle cells to cause them to relax. What type of signaling is this?

• Direct contact

• Paracrine signaling

• Long distance signaling

• Endocrine signaling

Small non-protein molecules and ions such as calcium are used as ________________ in cell signal transduction.

• Ligands

• Receptors

• Second messengers

• Protein kinases

Which of the following is NOT a possible cellular response to a signal transduction pathway being activated?

• Change in membrane permeability

• Enzymes activated or inactivated

• Change in gene expression

• Mutation of DNA

What is the function of protein kinase in cell signaling?

• It dephosphorylates other kinases and inactivates them

• Decreases amount of cAMP

• Dampens a signal and decreases cell response

• Phosphorylates proteins inside of the cell

What structure do plants use for signaling between adjacent cells?

• Gap junctions

• Chloroplasts

• Plasmodesmata

• Cell plate

A type of feedback that reduces the effect of the stimulus is known as

• Negative feedback

• Positive feedback

• Neutral feedback

Tags

NGSS.HS-LS1-3

True or false: Homeostatic feedback systems are mostly negative feedback systems.

• True

• False

Tags

NGSS.HS-LS1-3

Insulin is a protein hormone released by the beta cells of the pancreas in response to an elevated blood glucose. What would you expect to see in a person whose pancreas does not make insulin?

• Lower than normal blood glucose

• Normal blood glucose

• Higher than normal blood glucose

Tags

NGSS.HS-LS1-3