Basics of Communication Flashcards
List the three types of signalling between cells
Free diffusion between cells
Via cytoplasmic connections
By direct cell-to-cell contact
True or False:
Free diffusion is the fastest way for a signal to be sent between cells
False
Cytoplasmic connections are the fastest way for a signal to be sent between cells
True or false:
Cytoplasmic connections are the fastest way for a signal to be sent between cells
True
What are the cytoplasmic connections between cells in animals?
Gap junctions
What are the cytoplasmic connections between cells in plants?
Plasmodesmata
Signalling and reception by free diffusion to and from the same cell is called what?
Autocrine diffusion
Signalling and reception by free diffusion to and from nearby cells is called what?
Paracrine diffusion
Signalling and reception by free diffusion to and from distant cells is called what?
Endocrine (hormones)
What is the fastest form of free diffusion?
Autocrine
What is the slowest form of free diffusion?
Endocrine
What is autocrine diffusion important for?
Cell division, growth, regulation
What is paracrine diffusion important for?
Nerves, embryonic development
What is endocrine signalling important for?
Secreting hormones, homeostasis
True or False:
Endocrine glands are ductless
True
True or False:
Endocrine glands have ducts
False
What signalling do muscle cells of the heart use to contract almost simultaneously?
Muscle cells in the heart communicate by cytoplasmic connections (fastest mode of cell-cell communication)
Via gap junctions
How can cells recognise other cells in animals?
Via cell to cell contact, interactions between their surface molecules and receptors.
What is cell-to-cell contact important for in the body?
Embryonic development and immune response
What is signalling by cell-to-cell contact?
Specific interactions between surface molecules on one cell and receptors on another cell
True or False:
Growth factors are local regulators
True
What are growth factors?
Peptides or proteins that stimulate cell proliferation
Can have more than one target cell & might affect different cell types differently
Give an example of a growth factor
Nerve Growth Factor (NGF) - small protein that regulates growth of target neurones
True or False:
Gases can be local regulators
True
Nitric oxide acts as a paracrine signal molecule
What is nitric oxide synthesised from?
Amino acid arginine by nitric oxide synthase
What does the paracrine signal molecule nitric oxide do?
Induces vasodilation in cardiovascular system
Used in viagra to help with erectile dysfunction
True or False:
Prostaglandins are modified fatty acids
True
True or False:
Prostaglandins are local regulators
True
What are the functions of prostaglandins?
Causes contractions of uterine wall during childbirth to get stronger (secreted by placenta, induces labour) (POSITIVE FEEDBACK LOOP)
Induces fever in the body and inflammation in local area of infection
True or false:
Aspirin and ibuprofen inhibit prostaglandin synthesis
True
Prostaglandins induce fever in the body and inflammation in local area of infection. Inhibition of this alleviates pain.
True or false:
Neurotransmitters are local regulators
True
List four neurotransmitters
Acetylcholine
Biogenic amines (eg; serotonin)
Amino acids (eg; Glutamate)
Neuropeptides (eg; endorphines)
True or False:
All neurotransmitters are always either inhibitory or excitatory
False
Some neurotransmitters can be either inhibitory or excitatory depending on their target
