Physiology Quiz 2 - Chem 3&4, Cell Structure & Function

Primary Structure

The sequence of amino acids that form the polypeptide chain

Secondary Structure

Protein structure achieved when alpha-helical or beta-pleated regions of the polypeptide chain fold upon one another to produce a compact ball-like /globular molecule.

Tertiary Structure

Protein structure represented by alpha-helices and beta-sheets.

Quaternary Structure

Two or more polypeptide chains – each with its own tertiary structure.

How many amino acids are there?

20

Collagen

Structural protein found in hair, fingernails, feathers, horns, cartilage, tendons.

Antibodies

Protective protein that helps fight invading microorganisms and coagulates blood.

Insulin

Regulatory protein that controls cell activity and constitutes some hormones.

Actin & Myosin

Contractile protein that allows muscles to contract, the heart to pump, and sperm to swim.

Hemoglobin

Transport protein that carries molecules such as oxygen around your body.

Amino Acid

Contains amine group, acid group, and R-group.

R-group is what differentiates amino acids.

GlycineGlycine

Serine

Alanine

Enzyme

Proteins that initiate and speed up chemical reactions.

EX: Lactase breaks down lactose for energy.

Substrate

Substance that enzymes act on.

Describe the structure and function of carbonic anhydrase.

A zinc-containing enzyme that catalyzes the reversible hydration of carbon dioxide: CO2+ H2O<-->HCO3(-)+H+

Dehydration Synthesis

The acid group of one amino acid is bonded to the amine acid group of the next, with loss of a water molecule.

Hydrolysis

Peptide bonds linking amino acids together are broken when water is added to the bond.

Transcription

DNA is converted to RNA; DNA is decoded into mRNA.

Steps of Protein Synthesis

1. DNA

2. Transcription

3. RNA Maturation

4. Translation

Isotonic

Cells retain their normal size and shape; concentration is same inside and outside cell; water moves in and out without net change.

Hypertonic

Solute concentration inside cell is less than outside; cells lose water by osmosis, shrink, and become crenated.

Hypotonic

Solute concentration inside cell is greater than outside; cells take on water, swell, and may burst (lyse).

Simple Diffusion

Does not require assisstance from membrane transporter or energy; passive transport.

Facilitated Diffusion

Requires assistance from membrane transporter, oftentimes a protein; always goes from higher concentration to lower concentration.

Active Transport

Cell uses energy to move solute across the membrane; requires transfer proteins that combine with transport substances; moves ions; active transport & vesicular transport.

Exocytosis

A process for moving large molecules out of the cell to the cell exterior

Endocytosis

Cells take in substances from outside of the cell by engulfing them in a vesicle.

Fats

Long-term energy storage and insulation.

How many calories in 1 gram of fat?

9

How many calories in 1 gram of protein or CHO?

4

Saturated fats

Fats: solid at room temp

Unsaturated fats

Oils; liquid at room temp

Hydrophilic

Water-loving

Hydrophobic

Water-fearing

What is the purpose of cholesterol?

Cholesterol is the basis for all asteroids formed in the body and is essential to human life; synthesizes vitamin D.

Types of steriods

Estrogen, Testosterone, Cortisol,

Extracellular fluid

Found outside of cell.

• Plasma

• Interstitial fluid

Intracellular fluid

Found inside of cell.

Sterols

Regulate growth and development.

Phospholipids

Form the membranes that enclose cells.