Anatomy & Physiology - Lecture Notes Review (Flashcards)

Scenario: 2 patients, AB+ and O−; only one unit of O− blood is available.
Principle: O− is the universal red blood cell donor; AB+ is a compatible recipient for O− RBCs.
Priority guideline: Allocate the O− unit to the patient with the fewest transfusion options (the O− patient), because an O− recipient can only receive O− blood, whereas AB+ can receive other compatible RBCs if needed later.
Why it matters: Quick, compatible transfusion saves lives; preserving the scarce universal donor unit for the patient with the least options minimizes risk of incompatibility.

CHNOPS are the six most abundant elements in the body:
- Oxygen (O): 65 ext{%}; part of water; needed for cellular respiration.
- Carbon (C): 18.5 ext{%}; backbone of organic molecules.
- Hydrogen (H): 9.5 ext{%}; found in nearly every compound.
- Nitrogen (N): 3.2 ext{%}; part of proteins and nucleic acids.
- Phosphorus (P): 1.0 ext{%}; bones, teeth, nucleic acids, ATP.
- Sulfur (S): 0.3 ext{%}; part of some proteins.
Note: Many trace elements are present in smaller amounts (e.g., iodine, iron, calcium).

Water content ~ 62% of body weight; remaining ~38% includes proteins, minerals, carbohydrates, fats, etc. (illustrative breakdown on the slide).

Acids release H⁺ in water; bases release OH⁻; neutral solutions have equal amounts of both.
pH: acids < 7, bases > 7, neutral = 7.

Buffers maintain pH by absorbing/releasing H⁺.
Blood buffer: bicarbonate (HCO₃⁻).
Alkalosis/acidosis can be compensated by breathing rate changes (CO₂ removal) and renal bicarbonate handling.

Organic compounds: carbon-based, covalent bonds (usually with H).
Most organic compounds are polymers; monomers are the building blocks; polymerization forms polymers.

Nucleic Acids: DNA, RNA, ATP; nucleotides contain a phosphate, a 5-carbon sugar, and a nitrogenous base.
Carbohydrates: made of C, H, O.
- Monosaccharides (e.g., glucose) – short-term energy.
- Disaccharides (e.g., sucrose, lactose) – short-term energy.
- Polysaccharides (e.g., starch, glycogen, cellulose) – long-term energy storage or structural roles.
Lipids: mainly C and H; not polymers; hydrophobic; include fats, steroids.
Proteins: polymers of amino acids (20 amino acids).

Triglycerides: glycerol + 3 fatty acids; primary body fat; can accumulate in arteries.
Phospholipids: two fatty acids + phosphate group; hydrophilic head, hydrophobic tails; form cell membranes (bilayer, liposomes, micelles).
Steroids: four-ring structure; cholesterol, testosterone, cortisol, estrogen.

Proteins are polymers of 20 amino acids.
Functions include: support (collagen), movement (muscle), transport (membrane transporters), buffering (blood proteins), metabolic regulation (enzymes), coordination (hormones), defense (antibodies).
Protein structure levels: Primary → Secondary (α-helix, β-sheet) → Tertiary → Quaternary.
Denaturation: loss of normal structure and function due to heat or acid; often irreversible.

Enzymes are proteins that speed up chemical reactions.
Substrate binds to active site to form enzyme–substrate complex; products are released.
Lock-and-key model: specificity between enzyme and substrate.

Anatomy: structure (morphology) of body parts.
Physiology: function of body parts.
Historical context: Restrictions on dissection; later rise in demand led to body snatching by resurrectionists.
Notable case: Burke and Hare (early 19th century); Burke hanged 1829; body used for dissection; skeleton displayed in Anatomical Museum.

Sequence: Chemical level → Cellular level → Tissue level → Organ level → Organ system level → Organism level.
Example for each level:
- Chemical: water molecule (H₂O).
- Cellular: neuron cell.
- Tissue: cardiac muscle tissue.
- Organ: heart.
- Organ system: circulatory system.
- Organism: human.