4.2 Cell communication flashcards

local signaling

communicating with nearby or adjacent cells

Autocrine signaling

when a cell sends and receives its own signal

Paracrine signaling

involves one cell secreting molecules that act on target cells

Paracrine signaling example

growth factors, which stimulate nearby target cells to grow and divide

long distance signaling

communicating with distant cells

endocrine signaling

A type of long-distance signaling in animals that utilizes hormones.

how the endocrine system sends signals

hormones through the lymphatic fluid and circulatory system

insulin

A protein hormone synthesized in the pancreas that regulates blood sugar levels by facilitating the uptake of glucose into tissues

glucagon

A protein hormone secreted by pancreatic endocrine cells that raises blood glucose levels

All cells must be able to

communicate with one another

Cells generate, transmit, and respond to

chemical signals

Plasmodesmata

channels through cell walls that connect the cytoplasms of adjacent plant cells

Gap junctions

provide cytoplasmic channels between adjacent animal cells

Helper T cells

cells that help the immune system by increasing the activity of killer cells

What are antigens?

Any membrane-bound surface molecule in which an antibody can bind to.

What do antigens do?

Antigens elicit an antibody response.

synaptic signaling

a nerve cell releases neurotransmitter molecules into a synapse, stimulating the target cell

Neurotransmitters

chemical messengers that cross the synaptic gaps between neurons

synapse

The junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron

synaptic cleft

The narrow gap that separates the presynaptic neuron from the postsynaptic cell.

dendrite

Branchlike parts of a neuron that are specialized to receive information.

axon tip

Part of the neuron that uses chemical messengers to pass an impulse to the next cell.

Schwan cell

wraps around axon; produces mylin

myelin

a fatty substance that helps insulate neurons and speeds the transmission of nerve impulses