AP Biology Unit 4 Review Questions

1.Fill in the blanks: In direct contact communication, animal cells communicate through _______ junctions and plant cells communicate through _________.

• nuclear pores and chloroplasts
• tight junctions and desmosomes
• synaptic junctions and cell walls
• gap junctions and plasmodesmata

What would happen to the signal transduction pathway if protein kinase was mutated?

• The signal transduction pathway would be enhanced.
• If protein kinase was mutated, the signal transduction pathway would not be activated and therefore no

  signal would be relayed.

• The signal transduction pathway would remain unaffected.
• The signal transduction pathway would be reversed.

Tags

NGSS.HS-LS3-2

What do animals use for long distance signaling?

• blood cells
• Endocrine signaling - Specialized cells release

  hormones into the circulatory system where they reach target cells.

• neurons
• sound waves

What do plants use for long distance signaling?

• Water
• Sunlight
• Nutrients
• Hormones that travel

  throughout the plant and vascular tissue (xylem and phloem) or through the air to reach the target tissues.

What is the difference between paracrine signaling and synaptic signaling.

• Paracrine signaling and synaptic signaling occur in different locations of the body.
• Paracrine signaling releases local regulators via exocytosis to an adjacent cell. Synaptic signaling only

  occurs in animal nervous system cells. It occurs when neurons secrete neurotransmitters that will diffuse

  across the synaptic cleft.

• Paracrine signaling and synaptic signaling have the same mechanism of communication.
• Paracrine signaling and synaptic signaling are both types of endocrine signaling.

True or false: insulin signaling is an example of local signaling.

• False, long distance signaling

• Insulin signaling is an example of hormonal signaling
• False. direct signaling

• True

Tags

NGSS.HS-LS1-3

If you were given a problem on the AP exam that described a water-soluble (polar) receptor, where would it be located in the cell?

• cell membrane
• intracellular fluid

• cytoplasm
• nucleus

What happens in Stage 1 of cell signaling

• Reception occurs when a receptor in the target cell receives the ligand.

• Transduction is the conversion of

  an extracellular signal to an intracellular signal in a signal transduction pathway that is amplified and

  relayed by second messengers.

• Response occurs when the signal pathway converts the signal to a response

  that will alter a cellular process, most commonly turning genes on and off.

• Reactivation occurs when the cell reengages in communication.

What happens in Stage 2 of cell signaling

• Reception occurs when a receptor in the target cell receives the ligand.

• Transduction is the conversion of

  an extracellular signal to an intracellular signal in a signal transduction pathway that is amplified and

  relayed by second messengers.

• Response occurs when the signal pathway converts the signal to a response

  that will alter a cellular process, most commonly turning genes on and off.

• Reactivation occurs when the cell reengages in communication.

What happens in Stage 3 of cell signaling

• Reception occurs when a receptor in the target cell receives the ligand.

• Transduction is the conversion of

  an extracellular signal to an intracellular signal in a signal transduction pathway that is amplified and

  relayed by second messengers.

• Response occurs when the signal pathway converts the signal to a response

  that will alter a cellular process, most commonly turning genes on and off.

• Reactivation occurs when the cell reengages in communication.

Tags

NGSS.HS-LS1-3