BIO200 Unit 3.1

What does communication between cells require?

A Ligand and Signal Transduction

Define Ligand

A signaling molecule

Define Receptor Protein

Molecule the ligand binds to

Define Signal Transduction

Process that converts the information in the signal from ligand into a cellular response

Where is the membrane receptor located?

It can be located in the cell membrane or the cell itself

What are the four types of cell signaling?

Direct Contact, Paracrine Signaling, Endocrine Signaling, and Synaptic Signaling

Define Direct Contact Cell Signaling

Gap junctions and plasmodesmata allow signals to pass between adjacent cells

Define Paracrine Signaling

Signal released from a cell has an effect on neighboring cells

Define Synaptic Signaling

Nerve cells release a signal which binds to receptors on nearby target cells causing a synaptic gap

Define Endocrine Signaling

Hormones released from an endocrine cell travel through circulatory system to affect other cells throughout the body

Define Signal Transduction

When a ligand binds to a receptor protein, the cell has a response

What are cells called that have similar responses to the same signal?

Glucagon

What are cells called that have different responses to the same signal?

Epinephrine

What is the purpose of Phosphorylation

To turn signals on and off from ligand

Define Kinase

An enzyme that adds a phosphate group to a protein

Define Phosphatase

An enzyme that removes a phosphate group from a protein

Where are Intracellular receptors located?

Within the cell

Where are cell surface receptors located?

On the plasma membrane in order to bind a ligand outside the cell

What are the three major groups of membrane receptors?

Chemically gated ion channels, Enzymatic receptors, and G protein-coupled receptor

Define Chemically gated ion channels

Channel-linked receptors that open to let a specific ion pass in response to a ligand

Define Enzymatic Receptors

Receptor is an enzyme that is activated by the ligand

Define G protein-coupled receptor

A G-protein assists transmitting the signal from the receptor to enzyme

What is the purpose of Receptor tyrosine kinases

It is a membrane receptor that influences cell cycle, cell migration, cell metabolism, and cell proliferation

What is the first part of The Insulin Receptor?

Insulin binds to the extracellular domain of the alpha subunit of the insulin receptor

What is the second part of The Insulin Receptor?

The beta subunit of the insulin receptor phosphorylates the other, allowing the insulin response proteins to be activated

What is the third part of The Insulin Receptor?

Phosphorylated insulin response proteins activate glycogen synthase

What is the fourth part of The Insulin Receptor?

Glycogen synthase converts glucose into glycogen