Final exam study guide

UNIT 1: ATOMS & MOLECULES

1. Common Chemical Elements in the Body

• Major elements:

  • Oxygen (O)

  • Hydrogen (H)

  • Carbon (C)

  • Nitrogen (N)

• These elements are found in various biological forms:

  • Proteins

  • Carbohydrates

  • Lipids

  • Water

  • Gases

2. Definitions of Key Terms

• Atom:

  • The smallest unit of an element retaining its chemical properties.

• Ion:

  • An atom that has gained or lost electrons, thus acquiring a charge (positive or negative).

• Element:

  • A pure substance that cannot be broken down by chemical means. Examples include O, C, H, N.

• Molecule:

  • A substance formed by two or more atoms joined together.

• Compound:

  • A substance that contains atoms from two or more different elements.

UNIT 2: THE CHEMISTRY OF WATER

1. Functions of Water in the Body

• Lubrication and Cushioning: Water acts as a lubricant in joints and cushions vital organs.

• Regulation of Body Temperature: Water helps maintain stable body temperature through sweat and respiration.

• Universal Solvent: Water facilitates biochemical reactions by dissolving various substances.

2. Water Molecule Structure

• Drawing a water molecule:

  • H2O - consists of two hydrogen atoms covalently bonded to one oxygen atom.

• A water molecule can form hydrogen bonds with other water molecules, demonstrating cohesion and enhancing its unique properties.

3. Dissolving Salts

• Water dissolves salts (ionic compounds) by surrounding the ions and separating them, a process driven by the attraction between the water molecules and the ions.

UNIT 3: BIOCHEMISTRY

1. Carbohydrates and Their Uses

• Energy Source: Carbohydrates provide energy and serve as structural components within the body.

• Sources:

  • Monosaccharides (simple sugars like glucose)

  • Disaccharides (e.g., sucrose, lactose)

  • Polysaccharides (e.g., starch, glycogen, cellulose)

• Major Lipids: Include triglycerides, phospholipids, and steroids, each performing critical biological functions.

2. Structural Differences Between Carbohydrates and Lipids

• Carbohydrates:

  • Comprised of monomers, typically arranged in ring structures, and contain carbon, hydrogen, and oxygen in a fixed ratio.

• Lipids:

  • Made up of glycerol and fatty acid chains, containing less oxygen. They form complex structures and are generally hydrophobic.

UNIT 4: CELL STRUCTURE & FUNCTION

1. Cell Components and Functions

• Cytoplasm: The inner fluid of the cell containing organelles.

• Plasma Membrane: Acts as the protective barrier regulating substance movement in and out of cells.

• Nucleus: Houses the cell's DNA and directs cellular activities.

2. Types of Proteins

• Integral Proteins: Involved in transport and span the membrane.

• Peripheral Proteins: Act as receptors or enzymes, located on the inner or outer membrane surfaces.

3. Active vs. Passive Transport

• Active Transport: Requires energy (ATP) to move substances against their concentration gradient.

• Passive Transport: Does not require energy, as molecules move down their concentration gradients.

4. Feedback Systems

• Negative Feedback: Restores homeostasis by counteracting changes (e.g., temperature regulation).

• Positive Feedback: Amplifies changes until a specific endpoint is reached (e.g., childbirth).

UNIT 7: BODY STRUCTURE

1. Anatomical Terms

• Proximal vs. Distal: Describes relative distances from the trunk of the body.

• Superficial vs. Deep: Indicates proximity to the surface of the body.

2. Organ Systems

• Major organs are categorized into body cavities, including thoracic and abdominopelvic cavities, with their respective functions.

UNIT 10: SENSORY SYSTEM

1. Vision Pathway

• Light travels through the cornea, pupil, and lens before reaching the retina where photoreceptors detect it. Higher sensitivity to light is aided by rods, while cones provide color vision.

2. Auditory Pathway

• Sound waves journey through the auditory canal, vibrating the tympanic membrane, subsequently transferred via ossicles to the cochlea for sound detection by the hair cells.

3. Balance Detection

• The vestibular system functions to maintain balance through the utricle and saccule for static balance and semicircular canals for dynamic movements.