Anatomy and Physiology Final Lecture

Anatomy

The study of the structure of the body parts and their relationships to one another.

Physiology

The study of how the body parts function and work together to carry out life activities.

Anatomical position

standing upright, facing forward, arms at sides, palms facing forward, feet slightly apart.

Superior

toward the head or upper part of the body; above

Inferior

away from the head or toward the lower part of the body; below.

Anterior (ventral)

toward the front of the body.

Posterior (dorsal)

toward the back of the body.

Medial

toward the midline of the body

Lateral

away from the midline of the body.

Proximal

closer to the point of attachment or origin.

Distal

farther from the point of attachment or origin

Superficial

toward or on the surface of the body.

Deep

away from the body surface; more internal.

Homeostasis

The maintenance of a stable internal environment in the body despite changes in external conditions.

The three components of a homeostatic control system…

1. Receptor: detects a change (stimulus)

2. Control Center: processes the information and decides on a response (usually the brain)

3. Effector: carries out the response to restore balance.

Negative feedback

A mechanism that reverses a change to keep a variable within a normal range. (body temperature regulation- if you get too hot, you sweat to cool down.)

Positive feedback

A mechanism that amplifies a change instead of reversing it, often used in processes that need a definite outcome (childbirth).

What happens if homeostasis is not maintained?

The body may not function properly, leading to illness, disease, or even death.

Normal body temperature?

98.6 degrees

An example of a homeostatic process involving the endocrine system

Regulation of blood sugar: the pancreas releases insulin when blood glucose is too high to help lower it.

Atom

smallest unit of an element that retains the properties of that element.

Ions

atoms or molecules that have gained or lost electrons, giving them a charge.

Cation

positively charged ions formed by the loss of electrons

Anion

negatively charged ions formed by the gain of electrons

Ionic bond

a bond formed between a metal and a nonmetal when electrons are transferred from one atom to another.

Covalent bond

a bond formed when two nonmetals share electrons.

Hydrogen bond

a weak attraction between a hydrogen atom and a more electronegative atom like oxygen or nitrogen.

Which bond is the strongest: ionic, covalent, or hydrogen.

Covalent is the strongest (biological systems), hydrogen is the weakest.

Solvent

the substance that does the dissolving (water in saltwater)

Solute

the substance that gets dissolved (salt in saltwater)

Solution

A homogeneous mixture where the solute is completely dissolved in the solvent.

Colloid

A mixture where particles are dispersed throughout but do not settle (gelatin, plasma)

Suspension

A mixture where particles are large enough to settle over time. (sand in water, blood)

Polar molecule

A molecule with an unequal sharing of electrons, creating partial positive and negative ends (water).

Nonpolar molecule

A molecule with equal sharing of electrons and no charge difference (oxygen gas, oil)

Electrolyte

A substance that dissolves in water and conducts electricity by releasing ions (salt, NaCl)

Non-electrolyte

A substance that dissolves in water but does not release ions or conduct electricity (sugar)

Acid

A substance that releases H⁺ (hydrogen ions) in solution; pH less than 7.

Base

A substance that accepts H⁺ or releases OH^- (hydroxide ions); pH greater than 7

pH

A scale that measures how acidic or basic a solution is, ranging from 0 (acidic) to 14 (basic), with 7 as neutral.

Four major biological macromolecules

carbohydrates, lipids, proteins, nucleic acids

Function of carbohydrates

provides quick energy and structural support (glucose, starch)

Function of lipids

store energy, insulate, and make up cell membranes (fats, oils, phospholipids)

Function of proteins

build and repair tissues, acts as enzymes and hormones (enzymes, hemoglobin)

Function of nucleic acids

store and transmit genetic information (DNA and RNA)

Monomer of protein?

Amino acid

Monomer of carbohydrate?

Monosaccharide (simple sugar)

Monomer of nucleic acids

Nucleotide

Do lipids have true monomers?

No not really, they are made of components like fatty acids and glycerol, but not repeating monomers like proteins or nucleic acids.