BIO 152: Exam 2

Topics 8-15

ligand

signaling molecule

signaling cell

releases the signaling molecules

responding cell

has receptor proteins that bind to the signaling molecule

true

T/F: only cells with that receptor will respond.

homeostasis

maintenance of stable internal environment

sensor

determine the stimulus value

integrator

compares the stimulus to the setpoint

effector

change the condition

red bone marrow

what is the effector: hypoxia, the kidney, EPO, red bone marrow, or RBS count?

negative feedback

counteraction of an effect by its own influence on the process giving rise to it

higher or lower

negative feedback changes a variable to be …

thermoregulation

how an organism maintains its internal temperature

endotherm

regulate their own internal temp.

ectotherm

conform to the temp. around them

endotherms

homeotherms are also called…

ectotherms

poikilotherms are also called…

energy

endotherms have a ______ cost.

environmental

ectotherms have a ______ cost.

small molecules, proteins, steroids

list the three types of signals

small molecules

biological molecules smaller than biomolecules; amino acids

proteins

signals like insulin

steroids

signals with a. cholesterol backbone; lipids

endogenous

made from within the body

exogenous

made outside of the body, then consumed

hydrophobic

lipids are characterized by being …

micelles

hydrophobic inside

lipid signals

micelles store ….

vesicle

aqueous solution inside

hydrophilic

vesicles carry ________ signals.

exocytosis

a process by which the contents of a cell are released to the exterior through fusion of the vacuole membrane with the cell membrane

exocytosis

signals are released by …

autocrine

signaling and responding cell are the same cell

immune system

and example of autocrine

direct

signal through contact and small passages between cells

gap junctions, plasmodesmata

examples of direct cell communication

endocrine

signals travel through the bloodstream

bulk transport

how do endocrine signals travel?

paracrine

communicate with nearby cells

20 mm

how far away can a paracrine cell communicate?

bulk transport, diffusion

endocrine signaling uses _______, while paracrine signaling uses__ _______.

receptor

protein in or on a cell that receive a ligand

1

how many ligand can use a receptor?

conformational change

change in the shape of a receptor

signal transduction

receptor activation = activity in the cell

ligand-gated, g-protein coupled, enzyme-linked, intracellular

list the 4 types of receptors

steroid

what type of signaling molecule os non-polar?

intracellular receptor

hormone goes through the plasma membrane, receptor migrates to nucleus, gene expression

cell surface receptor

located on the plasma membrane; receives hydrophilic signals

transduction

move signal from outside to inside the cell

extracellular domain

binding site for the ligand

transmembrane domain

hydrophobic amino acids, transducer signal to inside

intracellular domain

causes a cellular effect

extra, trans, intra

list the 3 domains of cell surface receptors

ion-channel linked receptor

change in membrane charge, signal travels

concentration gradient

in an ion-channel linked receptor, the activity depends on the …

ligand-gated, mechanically-gated, always open, voltage-gated

list the 4 types of ion channels

ligand-gated

channel that is cell signaled

mechanically-gated

channel that responds to stretch or pressure

always open

channel that is constantly open

voltage-gated

channel that responds to the charge of the membrane

g-protein coupled receptor

receptor changes shape, binds to g-protein, is activated

cAMP

acts as a second messenger, binds to enzymes to activate/inactivate them

second messenger

a substance whose release within a cell is brings about a response by the cell

amplify

second messengers _____ signals.

enzyme-linked receptors

inactive, dimerization, autophosphorylation, signal transduction

kinase

enzymes that transfers phosphate to a protein

phosphatase

enzyme that removes phosphate from protein

integration of signals

phosphorylation cascades allow for ________ from different sources.

release of subunits of protein complex

g-protein coupled receptor activation:

g-protein coupled receptor

causes enzyme that is a separate protein in the membrane to become active

dimerization of two of the same type of protein

activation of receptor kinases:

receptor kinase

causes enzyme that is part of the receptor to phosphorylate proteins

animals

the nervous system is only found in ______.

protists, fungi, plants, sponges

the nervous system is not in:

electrical difference

all eukaryotic cells have ___________ across membrane.

all complex multicellular organisms

which organisms have cellular communication?

jellies, bilateral animals

neurons are found in:

nerve net

no CNS, distributed network of neurons, stimulus = response

sea anemones, jellyfish, comb jellies

who has nerve networks?

pacemaker neurons

create rhythmic electrical signals, intrinsic

intrinsic

do not require input

bilateral animals

ganglia are found in:

ganglion

group of neurons in communication with each other

interneurons

neurons between sensory and motor neurons

sensory

what kind of neuron is the ganglia?

sensory, inter-, motor

list the order through which a stimulus would go

bilateral animals

centralization and cephalization are found in:

centralization

localization of ganglia in the central part of the body

ventral

most invertebrates have a nerve cord in the ________ side.

dorsal

most vertebrates have a spinal cord in the ________ side.

complex

ganglia allow for ________ reflexes.

less likely to be damages

what is the advantage of centralization?

cephalization

having a brain

nerve net

sea anemone and flatworms have _____ nervous system.

centralization

earthworms and insects have _____ nervous system.

cephalization

squid and frogs have _____ nervous system.

centralization

sensory processing by multiple neurons

neurotransmitter

chemical signals

convergence

merging information together

propagation

transmission of electrical signals