Cell Structure and Function

Flashcards generated from lecture notes on cell biology and transport mechanisms.

What is nursing?

The most common field students are going into from this class.

What was the purpose of the initial blue book questions about the homework assignment?

Used to gauge the student's understanding and time spent on the biological macromolecules assignment.

If Molecule A is on the left and Molecule B is on the right, is A a triglyceride or monosaccharide, and what is B?

A is a triglyceride, B is a monosaccharide

Which macromolecule stores more energy, a triglyceride or a monosaccharide?

Triglyceride

What reasons back the higher level of stored energy in Triglycerides?

Triglycerides have more bonds and are the molecules in which fats are stored.

What three things do all cells contain?

DNA, ribosomes, and a cell membrane.

What is the function of DNA?

Instructions to run the cell.

What is the function of ribosomes?

Structure responsible for making proteins.

What are cell membranes made of?

Phospholipids.

What is one of the most fundamental differences between eukaryotic and prokaryotic cells?

The presence of organelles.

Name some organelles that are present in Eurkaryotic cells?

The nucleus and mitochondria.

What is cytoplasm?

Watery stuff inside the cell

What does ICF stand for?

Intracellular fluid

What does ECF stand for?

Extracellular fluid

A waterproof barrier is made of what?

phospholipids

What are the two different ways that substances get transported across a cell membrane?

Passive transport and active transport.

What is passive transport?

Requires no energy input.

In what direction does a molecule move during passive transport?

From an area of high concentration to an area of low concentration.

What causes diffusion?

Molecules are constantly moving and bumping into each other.

What is the state called when molecules are evenly distributed in a solution, but the molecules are still moving?

Dynamic equilibrium.

What is a selectively permeable membrane?

A membrane that allows some substances to cross but not others.

What occurs during simple diffusion?

Molecules move directly through the phospholipid bilayer.

What kind of molecules can move via simple diffusion?

Small and nonpolar.

What occurs during facilitated diffusion?

Molecules move through proteins embedded in the cell membrane.

What kind of molecules move via facilitated diffusion?

Big and/or charged and/or polar.

What are channel proteins?

Tunnels that are open to both the intracellular and extracellular fluid.

What are carrier proteins?

Proteins that change shape to move molecules across the membrane.

What is osmosis?

Facilitated diffusion of water.

Water moves through what water channel?

aquaporin

What determines water movement?

The number of solute molecules.

What do lower solute concentrations correspond to?

Higher water concentration.

What term describes the extracellular fluid?

Tonicity

What occurs in an isotonic solution?

Solute concentration in the extracellular fluid is the same as in the intracellular fluid.

What occurs in a hypotonic environment?

Lower solute concentration in the extracellular fluid.

What is it called when water concentration is too high and solute concentration is too low in the blood?

Hyponatremia

What occurs in a hypertonic environment?

Higher solute concentration in the extracellular fluid.

What is the shriveling of a cell called?

Crenation.

What is active transport?

Moving molecules from a low concentration to a high concentration.

What does active transport require?

Requires an input of energy.

What pump is used to move sodium and potassium to maintain disequilibrium across the cell membrane?

Sodium-potassium pump.

What molecule provides energy for the sodium-potassium pump?

ATP

What two things need to happen in the sodium potassium pump?

Sodium and potassium need to be in disequilibrium across the cell.