The structural and functional unit of life

Cell

What are the common structures of all cells?

Plasma membrane, cytoplasm, and nucleus

The control center of the cell

Nucleus

This is a lipid bilayer that separates intracellular fluid from extracellular fluid

Plasma membrane

True or False: Interstitial fluid is extracellular fluid that surrounds cells

True.

The plasma membrane is made up of what?

Phospholipids, glycolipids and cholesterol

The phosphate heads of the plasma membrane are ________ and _________.

Polar, hydrophilic

The fatty acid tails of the plasma membrane are ________ and ________.

Nonpolar, hydrophobic

The _________ of the plasma membrane increases stability.

Cholesterol

What are the types of proteins in the plasma membranes?

Integral and peripheral

Integral proteins are _________, while peripheral proteins are ________.

Imbedded, free floating

These types of proteins in the plasma membrane function as transport proteins (channels and carriers), enzymes, or receptors

Integral proteins

These types of proteins in the plasma membrane function as enzymes, motor proteins for shape change during cell division and muscle contraction; cell-to-cell connections

Peripheral proteins

List the functions of plasma membrane proteins

Transport, receptors for signal transduction, attachment to cytoskeleton and extracellular matrix, enzyme activity, intercellular joining, and cell-to-cell recognition

This makes up 20% of the outer membrane surface

Lipid rafts

Lipid rafts contain:

Phospholipids, sphingolipids, and cholesterol

What is the "sugar covering" at the cell surface?

Glycolax

This is what allows the immune system to recognize self from non-self, but cancerous cells change it continuously

Glycolax

Cell junctions can be ______ (like blood cells and sperm cells), or ______.

Free, bound into communities

What are the ways that cells are bound in communities?

Tight junctions, desmosomes, gap junctions.

In what type of junction do adjacent proteins fuse to form an impermeable junction encircling the cell?

Tight junctions

What type of junction has rivets or spot-welds that anchor cells together at plaques (thickenings on the plasma membrane)?

Desmosomes

In what type of junction to transmembrane proteins form pores (connexons) that allow small molecules to pass from cell to cell?

Gap junctions

Where might you find gap junctions?

For spread of ions, simple sugars, and other small molecules between cardiac or smooth muscle cells

This surrounds the cell and contains amino acids, sugars, fatty acids, vitamins, hormones, salts, waste product and water

Interstitial fluid

Plasma membranes are _______ _________.

Selectively permeable

What are the ways in which substances cross the plasma membrane?

Passive processes and active processes

In this type of process, no ATP is required and substances move down the concentration gradient.

Passive

In this type of process, ATP is required and it occurs only in living cell membranes

Active

What are the types of passive transport?

Diffusion, filtration

What are the types of diffusion?

Simple, carrier and channel-mediated, and osmosis

This type of passive transport usually occurs across capillary walls

Filtration

During diffusion, collisions cause molecules to move down or with their ________ __________.

Concentration gradient

The speed of diffusion is influenced by __________ and ___________

Molecule size and temperature.

Molecules will passively diffuse through the membrane if they are _______ soluble.

Lipid

Molecules will passively diffuse through the membrane if they are small enough or assisted by _________ __________.

Carrier molecules

Which vitamins are water soluble?

Vitamins B and C

Which vitamins are fat soluble

All other vitamins besides B and C

Which lipophobic molecules require facilitated diffusion?

Glucose, amino acids, and ions

During this type of facilitated diffusion, integral proteins assist and the binding of substrate causes shape change and then passage across the membrane.

Carrier-mediated diffusion

During this type of facilitated diffusion, aqueous channels are formed by transmembrane proteins and selectively transport ions or water.

Channel-mediated diffusion

These types of channels are always open.

Leaky

These types of channels are controlled by chemical or electrical signals

Gated

This type of passive process involves the movement of solvent across a selectively permeable membrane

Osmosis

What is the measure of the total concentration of solute particles?

Osmolarity

What is the back pressure of water on the membrane?

Hydrostatic pressure

What is the tendency of water to move into cell by osmosis?

Osmotic pressure

What is the ability of a solution to alter the cell's water volume?

Tonicity

When a solution has the same amount of non-penetrating solute concentration as the cytosol (same amount inside and outside), it is called?

Isotonic

When the solution has a higher non-penetrating solute concentration than cytosol (more solute outside), it is?

Hypertonic

When the solution has a lower non-penetrating solute concentration than cytosol (more inside than out), it is ?

Hypotonic

If there is more solute in the cell than outside the cell, water will move _______ the cell.

Into

If there is more solute outside the cell than in the cell, water will move _______ the cell

Out of