Question

Question 18

Which of the following is a type of local signaling in which a cell secretes a signal molecule that affects neighboring cells?

		hormonal signaling
		autocrine signaling
		paracrine signaling
		synaptic signaling

Question 19

Hormones are chemical substances produced in one organ that are released into the bloodstream and affect the function of a target organ. Which of the following conditions is required for the target organ to respond to a particular hormone?

		Cells in the target organ must modify their plasma membranes to allow the hormone to enter the cytoplasm.
		The target organ must be the same as the organ that produced the hormone.
		The target organ must have the opposite mating type of the organ that produced the hormone.
		The target organ must have receptors that recognize and bind the hormone molecule.

Question 20

Use the following figure to answer the question.

Which of the following types of signaling is represented in the figure?

		autocrine
		paracrine
		hormonal
		synaptic

Question 21

In the figure, the dots in the space between the two structures represent which of the following?

		receptor molecules
		signal transducers
		neurotransmitters
		hormones

Question 22

Which of the following statements about a G protein signaling pathway is true?

		A G protein-coupled receptor bound to GTP is in its active state.
		A G protein bound to GTP is in its active state.
		A G protein bound to GDP is in its active state.
		Hydrolysis of bound GTP by a G protein activates the G protein.

Question 23

One of the major categories of receptors in the plasma membrane functions by forming dimers, adding phosphate groups, and then activating relay proteins. Which type does this?

		G protein-coupled receptors
		ligand-gated ion channels
		steroid receptors
		receptor tyrosine kinases

Question 24

The activation of receptor tyrosine kinases is characterized by

		dimerization and phosphorylation.
		dimerization and IP3 binding.
		a phosphorylation cascade.
		GTP hydrolysis.

Answer 1

18. Paracrine signaling

In cell singalling, the signals produced by the cell either percieved by the same cell or neighbouring cell or moves through any stream of body and activates a cell that is outside the tissue

If the signal activates a neighbor cell , it is paracrine signaling

19.The target organ must have receptors that recognize and bind the hormone molecule

Cell signalling through hormones occur by binding of hormones to the receptors of target organ. Once the hormone is released it either bind with receptor of same cell or neighbor cell or moves through blood stream and activates another target organ by binding with its receptor

20. Synaptic

The figure represents synaptic signalling of neurons

21. Neurotrasnmitters

Neurotransmitters are hormones that transit the signal from 1 neuron to another neuron

22.G protein bound to GTP is in its active state

G rpotein coupled receptors activated and than they bonds to GTP once activated and than downstream signalling pathway will be activated

23.