Membranes: Permeability and Transport

Flashcards covering membrane permeability, osmosis, tonicity, electrochemical gradients, and types of transport including clinical correlates like diabetes mellitus.

Membranes are considered __________ or selectively permeable structures that define cell boundaries.

semipermeable

The movement of molecules from areas of high concentration to low concentration due to random kinetic motion is known as __________.

diffusion

A state of __________ equilibrium is achieved as long as solutes can move or pass through the membrane.

dynamic

The movement of water molecules across an impermeable membrane from areas of low concentration to high concentration is called __________.

osmosis

__________ is defined as the concentration of all solutes in a solution, including penetrating solutes like glucose and urea.

Osmolarity

__________ refers to the concentration of non-penetrating solutes and is the basis for osmotic pressure.

Tonicity

The sum of the chemical and electrical driving force of charged solutes or ions is the __________ potential.

electrochemical

The kinetics of membrane protein-mediated diffusion follows a __________ curve, similar to enzyme kinetics.

hyperbolic

The __________ conformation model explains how membrane proteins change shape during the binding and transport of solutes.

alternating

__________ is an analytical technique used to identify and quantify molecules through their mass-to-charge ratio ($m/z$).

Mass spectrometry

The method that determines protein structure using the diffraction patterns of X-rays and requires crystallization of pure proteins is __________.

X-ray crystallography

In __________ electron microscopy, samples are flash frozen and suspended in amorphous ice to visualize macromolecule projections.

cryogenic

Simple diffusion directly across membranes occurs for gases like __________ and ${CO}_2$.

$$O_2$$

__________ diffusion involves the use of channel or carrier proteins but does not require energy.

Facilitated

Carrier proteins used in facilitated diffusion can be classified as uniport, symport, or __________.

antiport

Active transport moves solutes __________ the concentration gradient and requires energy.

against

Primary active transport couples the movement of molecules with a chemical reaction, such as __________ hydrolysis.

ATP

The Na-K ATPase pump causes the outward transport of __________ and inward transport of potassium.

sodium

Secondary active transport, or __________ active transport, couples movement with another molecule moving down its gradient.

indirect

Glucose enter peripheral tissues via glucose transporters, also known as __________.

GLUT

In the small intestine and kidney, glucose absorption occurs via __________ co-transporters.

sodium-glucose

Type 2 diabetes mellitus is characterized by peripheral insulin __________ and dysfunction in insulin secretion.

resistance

The presence of glucose in urine, often seen in diabetes patients, is called __________.

glucosuria

The Latin word __________ means "honey sweet."

mellitus

The primary pacemaker of the heart is the __________ node.

sinoatrial

Voltage-gated sodium channels in the sinoatrial node that allow for spontaneous heartbeats are called __________ channels.

funny