Anatomy and Physiology: Unit 1

anatomy

studies the structure of body parts and their relationships to one another

Physiology

concerns the function of the body, in other words, the how the body parts work and carry out their life-sustaining activities.

chemical level

atoms, molecules, and organelles

cellular level

• Single Cell

• Basic structural and functional unit of life

Tissues Level

• Group of similar cells which work together toward a specific function.

  • examples include blood, muscle, nerves, etc. 

Organ Level

•  Contains 2 or more types of tissue

Organ System Level

•  Organs that work closely together

Organismal Level

• All organ systems combined to make the whole organism.

Integumentary

Forms the external body covering, and protects deeper tissues from injury. Synthesizes vitamin D, and houses cutaneous (pain, pressure, etc.) receptors and sweat and oil glands.

Skeletal

Protects and supports body organs, and provides a framework the muscles use to cause movement. Blood cells are formed within bones. Bones store minerals.

Muscular

Allows manipulation of the environment, locomotion, and facial expression. Maintains posture, and produces heat.

Nervous

As the fast-acting control system of the body, it responds to internal and external changes by activating appropriate muscles and glands.

Endocrine

Glands secrete hormones that regulate processes such as growth, reproduction, and nutrient use (metabolism) by body cells.

Cardiovascular

Blood vessels transport blood, which carries oxygen, carbon dioxide, nutrients, wastes, etc. The heart pumps blood.

Lymphatic

Picks up fluid leaked from blood vessels and returns it to blood. Disposes of debris in the lymphatic stream. Houses white blood cells (lymphocytes) invol

Respiratory

Keeps blood constantly supplied with oxygen and removes carbon dioxide. The gaseous exchanges occur through the walls of the air sacs of the lungs.

Digestive

Breaks down food into absorbable units that enter the blood for distribution to body cells. Indigestible foodstuffs are eliminated as feces.

Urinary

Eliminates nitrogenous wastes from the body. Regulates water, electrolyte, and acid-base balance of the blood.

Reproductive

1. Male – overall function is to produce offspring. Testes produce sperm and male sex hormone, and male ducts and glands aid in delivery of sperm to the female reproductive tract. 

2. Female – Ovaries produce eggs and female sex hormones. The remaining female structures serve as sites for fertilization and development of the fetus. Mammary glands of female breasts produce milk to nourish the newborn.

Survival Needs

Nutrients, Oxygen, Water, Normal body temperature, Appropriate atmospheric pressure

Homeostasis

Condition of maintaining the body’s internal environjment in a relative constant state.

Homeostatic Imbalance

Anything that disturbs or alters the balance of the internal environment.

Receptor, control center, effector

Homeostatic Control mechanisms

Negative Feedback

• The output shuts off the original effect of the stimulus or reduces its intensity.

• Change in one direction results in feedback that causes a change in the opposite direction. 

• This is how most homeostatic control mechanisms function; similar to a thermostat.

Positive Feedback

• The result or response enhances the original stimulus so that the response is accelerated.

•  A change in one direction accelerates more change in the same direction. 

  • Rare in life; blood clotting, labor contractions, orgasm.

Energy

Capacity to do work

Chemical energy

Energy stored in bonds

Electrical energy

energy resulted from movement of charged particles

radiant/electromagnetic energy

Travels in waves (example: heat, visible light, ultraviolet light, and X rays)

Oxygen 65%, Carbon 18%, Hydrogen 10%, Nitrogen 3 %

What elements make of 96% of the body?

Protons

Carry positive charge, weigh 1 amu

Neutrons

No electrical charge, weigh 1 amu

Electrons

Negative Charge, 0 Amu

Atomic Number

Number of Protons in Nucleus, ex. ₃Li

Mass Number

Total number of protons AND neutrons in nucleus, ex. ⁷Li

Isotopes

•  Atoms contain same number of protons but differ in the number of neutrons they contain

  • Atomic numbers are same, but mass numbers different

Molecule

general term for 2 or more atoms bonded together

compound

specific molecule that has 2 or more different kinds of atoms bonded together 

Solutions

Homogenous mixtures

Solvent

substance present in greatest amount

Solute

substance dissolved in solvent

Colloids

Also known as emulsions; are heterogeneous mixtures, meaning that particles are not evenly distributed throughout mixture. Do NOT settle out.

ex. smoke, milk

Suspensions

Heterogeneous mixtures that contain large, visible solutes that do settle out.

ex. water & sand, blood

Electron Shells

Shell 1 can hold 2 e-, Shell 2 can hold 8 e-. outermost shell is called the valence shell

Octet Rule

Desire 8 Valence electrons in there out

Ions

atoms that have gained or lost electrons and become charged

Ionic Bonds

The transfer of valence shell electrons from one atom to another, resulting in ions

• One becomes an anion ( negative charge) 

  • Atom that gained one or more electrons

• One becomes a cation ( positive charge )  

  • Atom that lost one or more electrons

• Attraction of opposite charges results in an ionic bond

Covalent Bonds

Covalent Bonds are formed by sharing of two or more valence shell electrons between two atoms 

• 2 electrons results in a single bond

• 4 electrons is a double bond

• Sharing of 6 electrons is a triple bond

Nonpolar covalent bonds

Equal sharing of electrons between atoms 

ex. CO₂

Polar covalent bonds

Unequal sharing of electrons between 2 atoms 

dipole

Having 2 different charges

Hydrogen bonds

Attractive force between electropositive hydrogen of one molecule and an electronegative atom of another molecule

Synthesis

Used in anabolic process: A + B → AB

Decomposition

Involve catabolic (bond-breaking) reactions AB → A + B

Exchange Reactions

Bonds are both made and broken

AB + C → AC + B

and

AB + CD → AD + CB

Exergonic

net release of energy (give off energy)

• Products have less potential energy than reactants

•  Catabolic reactions

Endergonic

reactions result in a net absorption of energy (use up energy)

• Products have more potential energy than reactants

•  Anabolic reactions

temperature, concentration of reactants, particle size, Catalysts

The speed of chemical reactions can be affected by:

Biochemistry

Is the study of chemical composition and reactions of living matter

Inorganic Compounds

• Water, salts, and many acids and bases

  • Do not contain carbon

Organic Compounds

• Carbohydrates, fats, proteins, and nucleic acids

  • Contain carbon, are usually large, and are covalently bonded 

Acids

Proton donors that release H+

ex. HCL→H+CL

Acidic pH range is 0–6.99

Bases

Proton Acceptors that pick up H+ ions

ex. NaOH → Na⁺ + OH^–

Alkaline pH range is 7.01–14

Organic Compounds

• Organic molecules contain carbon

  • Exceptions: CO₂ and CO, which are inorganic

carbohydrates, lipids, proteins, and nucleic acids

Major organic compounds

Hydrolysis reactions 

Water splits: A water molecule breaks apart into a hydrogen ion (H+) and a hydroxyl group (OH−).

Parts attach: The hydrogen ion (H+) attaches to one of the new, smaller molecules, and the hydroxyl group (OH−) attaches to the other.

• Opposite of condensation: It is the reverse of a condensation (or dehydration synthesis) reaction, which joins molecules together and removes water

Carbohydrates

• include sugars and starches

• Contain C, H, and O

Monosaccharides

one single sugar

• Simple sugars containing three to seven carbon atoms

• (CH₂O)_n: general formula

  • n = number of carbon atoms

    • MONOMERS of Carbohydrates

Disaccharides

two sugars

• Formed by dehydration synthesis of two monosaccharides

  • glucose + fructose → sucrose + water

Polysaccharides

many sugars

• Polymers of monosaccharides

  • Formed by dehydration synthesis of many monomers

Ribose and deoxyribose

Pentose Sugars (5 carbon atoms)

Glucose (Blood sugars)

Hexose Sugars (6 carbon atoms)

Important disaccharides

Sucorse, Maltose, Lactose

Important Polysaccharides

• Starch: carbohydrate storage form used by plants

  • Glycogen: carbohydrate storage form used by animals

Lipids

• Contain C, H, O, but less than in carbohydrates, and sometimes contain P

• Insoluble in water

Triglycerides

• Called fats when solid and oils when liquid

• Composed of three fatty acids bonded to a glycerol molecule

• Main functions

  • Energy storage, insulation, and protection 

Saturated Fatty Acids

• All carbons are linked via single covalent bonds, resulting in a molecule with the maximum number of H atoms (saturated with H)

  • Solid at room temperature (Example: animal fats, butter)

Unsaturated Fats

• One or more carbons are linked via double bonds, resulting in reduced H atoms (unsaturated)

• Liquid at room temperature (Example: plant oils, such as olive oil)

• Trans fats – modified oils; unhealthy

• Omega-3 fatty acids – “heart healthy”

Phospholipids

• Modified triglycerides

  • Glycerol and two fatty acids plus a phosphorus-containing group

• “Head” and “tail” regions have different properties 

  • Head is a polar region and is attracted to water

  • Tails are nonpolar and are repelled by water

    • Important in cell membrane structure

Steroids

• Consist of four interlocking ring structure

Important Steroids

cholesterol, vitamin D, steroid hormones, and bile salts

Cholesterol

• Is building block for vitamin D, steroid synthesis, and bile salt synthesis

• Important in cell plasma membrane structure