Unit 1 Bio214

Anatomy

the study of the structure of the body

Physiology

the study of the function of the body

Inspection

to examine by viewing

Palpation

to examine by touch

Auscultation

to examine by listening

Percussion

to examine by tapping

Cadaver dissection

cutting and separating human body tissues to reveal tissue relationships

Comparative anatomy

study of multiple species to learn about form, function, and evolution

Radiology

branch of medicine concerned with imaging

Radiography (X-rays)

\-dense tissue appears white

\-over half of all medical imaging

\-classic, oldest, and most straight focused

Radiopaque substances

\-Injected or swallowed

\-fills hollow structures such as blood vessels and intestinal tract

computed tomography (CT) scan

\-formerly called a CAT scan

\-low-intensity X-rays and computer analysis

magnetic resonance imaging (MRI)

\-superior quality to CT scan

\-best for soft tissue

Positron Emission Tomography (PET)

\-assesses metabolic state of tissue

\-distinguishes tissues most active at a given moment

\-inject radioactively labeled glucose (shows what parts of the brain are active when injected)

Sonography

\-second oldest and second most widely used

\-high frequency sound waves echo back from internal organs

\-avoids harmful x-rays

\-preferred method for younger children

Gross anatomy

Study of structures that can be seen with the naked eye

Histology

examination of tissues with microscope

Cytology

study of structure and function of cells

The Hierarchy of Complexity

organism, organ systems, organs, tissues, cells, organelles, molecules, atoms

Anatomical Variation

No two humans are exactly alike

Characteristics of Life

organization, cellular composition, metabolism, responsiveness, movement, homeostasis, development, reproduction, evolution

Senescence

the degeneration that occurs in an organ system after the age of peak functional efficiency

What are the best ways to slow senescence?

good nutrition and exercise

What type of exercise reduces bone fractures?

resistance exercise

What do endurance exercises do?

\-reduce body fat

\-increase cardiac output and oxygen uptake

Life expectancy

average length of life in a given population

Life expectancy for male

76.2 years

Life expectancy for female

81 years

Life span

maximum age attainable by humans

There is no \_____ \_____ of biological death

definable instant

Homeostasis

maintaining a relatively constant internal environment

What does negative feedback allow for?

dynamic equilibrium within a limited range around a set point

Receptor

structure that senses change in the body (e.g., stretch receptors above heart that monitor blood pressure)

Integrating (control) center

control center that processes the sensory information, "makes a decision," and directs the response (e.g., cardiac center of the brain)

Effector

the cell or organ that carries out the final corrective action to restore homeostasis (e.g., the heart)

Negative Feedback

a mechanism of response in which a stimulus initiates reactions that reduce the stimulus

Positive Feedback

Feedback that tends to magnify a process or increase its output.

Self-amplifying cycle

\-leads to greater change in the same direction

\-response is the same as stimulus

\-feedback loop is repeated

\-change produces more change

\-e.g., contractions during childbirth

Normal way of producing rapid changes

Examples include: childbirth, blood clotting, protein digestion, and generation of nerve signals

Gradient

a difference in chemical concentration, charge, temperature, or pressure between two points

Matter and energy tend to flow \_____ gradients

down

Movement in the opposite direction is "\____ \____ \___"

\-"up the gradient"

\-low to high

\-requires spending metabolic energy

Chemicals flow down \____ gradients

concentration

Charged particles flow down \___ gradients

electrical

heat flows down \___ gradients

thermal

Element

simplest form of matter to have unique chemical properties

Atom

smallest piece of an element with the chemical and physical properties of the element

Atomic Number

\-the number of protons in the nucleus of an atom

\-most important for determining chemical and physical properties

How many elements have a biological role?

24

How many elements are 98.5% of body weight?

\-6

\-oxygen, carbon, hydrogen, nitrogen, calcium, phosphorus

Minerals

inorganic elements extracted from soil by plants and passed up the food chain to humans

How much body weight is constituted by minerals?

4%

Electrolytes

\-substances that ionize in water and form solutions capable of conducting electricity

\-mineral salts needed for muscle and nerve function

Ions

charged particle (atom or molecule) with unequal number of protons and electrons

Ionization

transfer of electrons from one atom to another

Anion

particle that gains electron(s) (negative ion)

Cation

particle that loses electron(s) (positive ion)

Ions with \____ charges are attracted to each other.

opposite

Electrolyte importance

\-chemical reactivity

\-osmotic effects (influence of water movement)

\-electrical effects on nerve and muscle tissue

Chemical bonds

hold atoms together within a molecule or attract one molecule to another

Ionic bonds

\-attractions between cations and anions

\-electrons donated from one atom to another

\-easily broken by water

Nonpolar bond

a covalent bond in which electrons are shared equally (strongest bond)

Polar bond

a covalent bond in which electrons are shared unequally (spend more time near oxygen)

Hydrogen bond

weak attraction between a slightly positive hydrogen atom in one molecule and a slightly negative atom

water molecules are \____ to hydrogen bonds

attracted

Molecule

chemical particle composed of two or more atoms united by a covalent chemical bond

Compound

molecule composed of two or more different elements

Molecular formula

identifies constituent elements and how many atoms of each are present

Mixtures

physically blended but not chemically combined

Body fluids are \___ \___ of chemicals

complex mixtures

Most mixtures in our bodies consist of chemicals dissolved or suspended in \___________.

water

Water is \____ to \____ of body weight

\-50%-75%

\-depends on age, sex, fat content, etc

Solvency

ability to dissolve other chemicals

Water is called the universal solvent because

it dissolves many substances

Hydrophilic

\-substances that dissolve in water

\-molecules must be polarized or charged (e.g., sugar)

Hydrophobic

\-substances that do not dissolve in water

\-molecules are nonpolar or neutral (e.g., fats)

Metabolic reactions depend on \____ \____ \____

solvency of water

Solution

consists of particles called the solute mixed with a more abundant substance (usually water) called the solvent

A solute can be a \_____________, \________________, or \_________________

gas, solid, or liquid

What is almost always the solvent in humans?

water

Acid

proton donor (releases H+ ions in water)

Base

proton acceptor (accepts H+ ions)

pH

a measure derived from the molarity of H+

What is a neutral pH?

7.0 (H+ \= OH-)

What is an acidic pH?

less than 7 (H+ \> OH-)

What is a basic pH?

greater than 7 (OH- \> H+)

Bases feel \____ to the touch

slippery

Can you have a negative pH?

yes

Energy

the capacity to do work

Kinetic energy

energy of motion

Potential energy

energy stored in an object but not currently doing work

Chemical energy

potential energy in molecular bonds

Chemical reaction

the making or breaking of chemical bonds

Reaction rates increase when \___

\-Reactants are more concentrated

\-temp rises

\-catalyst is present

Catalyst

substance that speeds up the rate of a chemical reaction

Organic chemistry

the study of compounds containing carbon

Four categories of carbon compounds

carbohydrates, lipids, proteins, nucleic acids

Macromolecules

very large organic molecules with high molecular weights

Polymers

macromolecules made of a repetitive series of identical or similar subunits (monomers)

Polymerization

joining monomers to form a polymer