University of Iowa: Fundamentals of Human Physiology, Exam 2 | Quizlet

Fluid Compartments

-Intersticial

-Plasma

-Intercellular

Extracellular Environment

Consists of:

-Fluid

-Matrix of polysaccharides and proteins

Connective Tissue

Tissue that has the most extracellular matrix

Protein Fibers

-Collagen

-Elastin

-Reticular

Ground substance

-Gelatinous

-Fills spaces in between cells

-Proteoglycans

Plasma Membrane Structure

Phospholipid bilayer

Plasma Membrane

Selectively permeable to small, non polar molecules

Transport

Cells needed to take materials in and out.

Non carrier mediated

-Diffusion

-Osmosis

-Water

No helper

Non-carrier mediated transport

Diffusion

Movement of particles in a solution due to random thermal motion; Lipid soluble and Ions

Carrier mediated transport

-Facilitated transport

-Active transport

Needs help

Carrier mediated transport

Characteristics of Diffusion

-Passive

-Random

-Does not need carrier

-Movement from high to low concentration

Diffusion

Example: Exchange of oxygen in lungs

Non polar

These molecules diffuse through the membrane easily.

Concentration gradient

The difference in the concentration of a substance between two locations.

Net Diffusion

"Down" a concentration gradient; high to low; left to right

No

Net diffusion continues until there is ____ difference in concentration.

Ion

Polar; needs to go through a channel to diffuse through membrane

Types of channels

Open and Gated

Warm

Temperature that makes the rate of diffusion increase .

Cold

Temperature that makes the rate of diffusion decrease.

Factors affecting rate of diffusion

-Magnitude of the concentration gradient

-Permeability of the membrane to the substance

-Surface area of the membrane across which diffusion is taking place

-Temperature of solution

Osmosis

Diffusion of water

Osmolarity

-The number of total solute particles per liter of solution

-Some solutions may have multiple kinds of solute

-Net diffusion of water will occur from the solution with the lower osmolarity to the one with the hight osmolarity

Net diffusion

__________ ___________ of water down its own concentration gradient.

Osmotic Pressure

Driving force that water wants to move with.

Higher

Water moves to areas of ______ osmolarity.

Tonicity

Effect of solute concentration on the osmosis of water; determines whether cell remains same size, swells, or shrinks when a solution surrounds the cell

Hypertonic solution

Cell Shrinks

Hypotonic solution

Cell swells

Isotonic solution

Cell stays the same size in a solution

Osmoreceptors

Sense osmolarity

Salt

Can increase osmolarity

Negative feedback

Regulation of blood osmolarity

Hypothalamus

Where osmoreceptors are found

Blood

Has a stable osmolarity

Increase osmolarity

Triggers:

-Thirst

-Anti-diuretic hormone (ADH)

ADH

Decreases excretion of water in urine.

Protein carriers

Carrier-mediated transport utilizes these carriers in plasma membrane

Characteristics of protein carriers

-Specificity

-Saturation

-Competition

Purpose of carrier mediated transport

Polar molecules can't get into the membrane

Small molecules transported along membrane

-Glucose

-Amino Acids

Steps of Carrier Mediated Transport

-Bind to transported substance on one side of the membrane

-Undergo shape change

-Release substance on opposite side of the membrane

Diffusion

Has no saturation

Saturation

Occurs with carrier only

Maximum rate of transportation

Due to Saturation

Facilitated Diffusion

-Different from diffusion because transporter proteins can become saturated

-Does not require energy

Glucose Transporters

GLUT

Active Transport

-Moves a substance against its concentration gradient

-Requires carrier molecule

-Requires energy

Types of Active Transport

-Primary active transport

-Secondary active transport

ATP

Primary active transport energy source

Na/K Pump

3 Na+ out and 2 K+ in

Secondary active transport

Does not use ATP

Co transport

Transport moving in same direction

Counter transport

Transport in opposite direction

Energy source of secondary active transport

An ion concentration gradient (Na+)

Trancellular

Transport across the cell

Paracellular

Transport around the cell

Tracts

Where epithelial cells are found

Types of interactions

-Tight junctions

-Adherens

-Desmosomes

Tight Junction

No paracellular just transcellular

Desmosomes

Strength building protein fibers that connect cells together; common in skin

Adherens

Adhesion that desmosomes are stronger than

Adherens

Cells "glued" together by specialized proteins; commonly found in heart muscle

Electrochemical gradient

When a cell is more negative inside than outside

-70mV

Resting membrane potential

Resting membrane potential

Important for generating electrical impulses and driving co-transport of other substances in the membrane

K+ channels

Open all the time which makes the interior of the cell more negative

Excitable tissues

Neurons and muscles; Can rapidly change their resting membrane potentials

Equilibrium Potential

An ionic concentration gradient across a membrane permeable to only one ion; theoretical

Cell signaling

Chemical signals between cells such as hormones

Types of intercellular communication

-Gap junction

-Paracrine signalling

-Synaptic signalling

-Endocrine signalling

Gap Junctions

Allow adjacent cells to pass ions and regulatory molecules through a channel between the cells

Use cell signaling

-Paracrine factors

-Neurotransmitters

-Hormones

-Gap Junctions

Target Cells

Posses receptor proteins that bind to specific signaling molecules

Receptors

-Polar molecules= Surface

-Nonpolar molecules= Inside

G Proteins

Made up of 3 subunits- Alpha, beta, and gamma

Alpha

Subunit that dissociates when a signal molecule binds to the receptor and travels to effector protein

cAMP

Second messenger after G protein couples to enzyme

Nervous System

Consists of:

-CNS

-PNS

CNS

-Brain and Spinal cord

-Function in control and integration

PNS

-Cranial nerves and spinal nerves

-Motor and sensory

Neurons

Nerve cells that conduct electrical signals

Neuroglia

-Majority of all nerve tissue cells

-Support neurons

Parts of neuron

-Dendrites

-Cell Body

-Axonal hillock

-Axon

-Axon terminal

Myelin

-Protective coating over the axon

-Makes the message through the axon flow faster and smoother

Types of neurons

-Afferent

-Efferent

-Interneurons

Afferent neurons

Carry signal away from the sensors

Efferent neurons

ANS; Sends info from CNS to trigger motor response

Interneurons

CNS; Communicate between sensory and motor neurons

Neuroglia

Non conducting cells; PNS and CNS; aid the neurons

Types of Neuroglia

-Schwann cells

-Oligodendrocytes

-Astrocytes

-Microglia

-Ependymal cells

Schwann cells

PNS; makes myelin

Oligodendrocytes

CNS; makes myelin

Astrocytes

-Form part of the blood-brain barrier

-Help make glucose for neurons

-Absorb extra neurotransmitters

Microglia

Part of the immune system in the brain

Ependymal cells

Help form CSF

Nerves and muscles

Excitable tissues