A&P I Essentials Review

Name the body parts and terms associated with it.

• Cranial – head/skull

• Cervical – neck

• Frontal – forehead

• Occipital – back of head

• Temporal – temples (sides of head)

• Aural – ear

• Oral – mouth

• Ocular – eye

• Axillary – armpit

• Brachial – arm

• Antebrachial – forearm

• Antecubital – front of elbow

• Carpal – wrist

• Digital – fingers/toes

• Thoracic – chest

• Abdominal – abdomen

• Pubic – genital region

• Inguinal – groin

• Umbilical – belly button

• Sacral – base of spine (above buttocks)

• Femoral – thigh

• Patellar – kneecap

• Pedal – foot

• Plantar – sole of foot

Describe the directional planes.

• Superficial vs. Deep → near surface vs. farther inside

• Anterior (ventral) vs. Posterior (dorsal) → front vs. back

• Superior vs. Inferior → above vs. below

• Medial vs. Lateral → toward midline vs. away from midline

• Proximal vs. Distal → closer to trunk vs. farther from trunk

What are the 3 planes

• Sagittal – divides left/right

• Frontal (coronal) – divides front/back

• Transverse (horizontal) – divides top/bottom

Describe Atoms, Molecules, and Compounds

Describe Bonds

🔹 Atoms, Molecules, Compounds

• Atom = smallest unit of an element (ex: oxygen atom).

• Molecule = 2+ atoms bonded (O₂).

• Compound = molecule with ≥2 different elements (H₂O, CO₂).

🔹 Bonds

• Ionic – transfer of electrons (Na⁺ + Cl⁻ in salt).

• Covalent – sharing electrons (O₂, H₂O).

  • Polar = unequal sharing (H₂O).

  • Nonpolar = equal sharing (O₂).

• Hydrogen – weak bond between molecules (between water molecules).

💡 Examples:

• Na⁺ + Cl⁻ → ionic

• H–O within one water → polar covalent

• Between water molecules → hydrogen

• O₂ molecule → nonpolar covalent

Describe pH levels

Example

🔹 pH

• Acid = releases H⁺ (ex: HCl, stomach acid).

• Base = accepts H⁺ / releases OH⁻ (ex: NaOH, ammonia).

• Neutral = pH 7.

• <7 = acidic, >7 = basic.

• pH scale is logarithmic → pH 1 vs pH 4 = 10³ = 1000x more acidic.

• Buffer = stabilizes pH (ex: bicarbonate in blood).

a. Acid

• Example: HCl (hydrochloric acid) in the stomach → releases H⁺ when dissolved in water.

b. Base

• Example: NaOH (sodium hydroxide) → releases OH⁻ that combines with H⁺ to form water.

Describe carbohydrates

Describe Lipids

Carbohydrates

• Monosaccharide → 1 sugar (glucose).

• Disaccharide → 2 sugars (sucrose).

• Polysaccharide → many sugars (glycogen).

• Hydrophilic (water-loving).

Lipids

• Carbon bonds: each carbon = 4 bonds.

• Saturated fatty acid = single bonds only (solid, animal fat).

• Unsaturated fatty acid = double bonds present (liquid, oils).

Components	Name
Glycerol + 1 fatty acid	Monoglyceride
Glycerol + 2 fatty acids	Diglyceride
Glycerol + 3 fatty acids	Triglyceride
Glycerol + phosphate + 2 fatty acids	Phospholipid

Describe the phospholipid bilayer.

Describe steroids.

• Phospholipid bilayer:

  • Heads = hydrophilic (like water).

  • Tails = hydrophobic (repel water).

• Steroids: derived from cholesterol (ex: testosterone, estrogen, cortisol).

Describe protein, nucleic acids, and ATP

Proteins

• Subunits = amino acids.

• 2 amino acids = dipeptide.

• Many amino acids = polypeptide.

• Globular = round, soluble (enzymes).

• Fibrous = long, strong (collagen, keratin).

• Denaturation = loss of shape → loss of function. Causes: heat, pH change, chemicals.

• Enzymes = biological catalysts (speed reactions).

Nucleic Acids

• DNA in nucleus.

• All cells contain DNA except RBCs.

• Gene = code for a protein.

• RNA types: mRNA, tRNA, rRNA.

• mRNA = carries copy of gene → ribosome.

ATP

• Full name: Adenosine Triphosphate.

• Reaction: ATP → ADP + Pi + energy.

Descibe Passive transport

Passive Transport

• Molecules move high → low concentration (down gradient).

• No ATP required.

• Can diffuse directly if small & nonpolar (O₂, CO₂, lipids).

• Larger/polar molecules need protein channels (facilitated diffusion). Ions and glucose

Describe Osmosis

Osmosis

• Movement of water across membrane.

• Uses aquaporins (water channels).

• Hypertonic solution → cell loses water (shrinks).

• Hypotonic solution → cell gains water (swells).

Decsribe active transport

Active Transport

• Molecules move low → high concentration (against gradient).

• Requires protein pump + ATP.