A&P Exam 1

Define Life

Order, Evolutionary Adaptation, Response to the Environment, Regulation, Energy Processing, Growth & Development, Reproduction

5 Environmental Factors of Life

1) Water 2) Oxygen 3) Food 4) Heat 5) Pressure

Water

Most abundant substance in the body

Required for metabolic processes

Required for transport of substances

Regulates Body Temp

Food

Provide Necessary Nutrients

Supplies Energy

Supplies Raw Material

Oxygen (gas)

1/5 of air

Release energy from nutrients

Heat

Form of energy

Partly controls rate of metabolic activity

Pressure

Application of force on an object

• Atmospheric pressure = breathing

• Hydrostatic pressure = blood flowing

Order of Organization of an Organism

Atom —> Molecule —> Macromolecule —> Organelle —> Cell —> Tissue —> Organ —> Organ System —> Organism

Emergent Properties

Result from the arrangement & interaction of parts within a system

• Characterize non-biological system example

• Ex. Functioning bike emerges only when all of necessary parts connect in the correct way

Biological Systems

combination of components that form a more complex organization

ex. cells, organism, & ecosystem

Physical laws & needs to exchange materail w/ the environment limits range of animal forms

Anatomy

study of structure of an organism

Physiology

study of functions an organism performs

Which keyboard more efficient?

Dvorak keyboard efficient than QWERTY but is what we use as its been accepted in society

Why are not all animals designed equally?

Natural Selection

Raw Materials

If natural selection strong + little variation or highly specialized = extinction

Physical laws + need to exchange materials with the environment limits range of animal forms

3 Important Figures in A&P

Galen - 165-200 AD (Greek) —> assembled anatomical knowledge, worked on Apes, 1300 Years, “The” reference = many mistakes

Leonard Da Vinci —> dissected 30 bodies before Pope stopped him

Andreae Vesalil —> De Humani Corporis Fabrica 1543

Homeostasis

Maintaining a stable internal environment

Homeostatic Control Mechanism

monitors aspects of the internal environment & corrects as needed —> variations are within limits

• Recepter - provides info about the stimuli

• Control Center - tells what a particular value should be (set point)

• Effector - elicits responses that change conditions in the internal environment

Negative Feedback Mechanisms

Prevent sudden, severe changes in the body

Corrects the set point

Causes opposite of bodily disruption to occur i.e. the “negative”

Most common feedback loop type

Ex. body temp, blood pressure, & glucose regulation

Positive Feedback Mechanisms

Increases (accelerates) the actions of the body

Short Lived

Do Not require continuous adjustments

Ex. blood clotting & child birth

Cranial Cavity

space inside the skull that holds & protects the brain

Vertebral Cavity

long narrow cavity inside the backbone that houses the spinal cord

Thoracic Cavity

second largest human body that is located inside the chest between the neck and diaphragm - organs = heart, lungs, trachae, thymus gland, major blood vessels

Diaphragm

dome shaped muscle that serves as the physical partition between the thoracic & abdominal cavity

Abdominal Cavity

largest hollow space in the body between the chest and the pelvis - organs = digestive systems (Stomach, liver, pancreas, spleen, and most of the intestine) & the excretory system (kidney & adrenal glands)

Pelvic Cavity

bowl shaped space located at the base of the trunk (below the abdomen) enclosed by the hip bones, sacrum, & coccyx

Organs = digestive system (The lower end of the large intestine, including the rectum and anal canal) & Urinary System (The urinary bladder and the upper parts of the urethra)

Visceral Layer

covers an organ

Parietal Layer

lines a cavity or body wall

Anatomical Terminology

standardized, often latin or greek

anatomical position - standing erect, facing forward, upper limbs at the side, palms facing forward & thumbs out

Posterior

Towards the back or rear portion of the human body

ex. the shoulder blades are posterior to the rib cage

Anterior

Towards the front of the body

ex. The shin is anterior to the spinal cord

Superior

Towards the head

ex. the head is superior to the knee

Inferior

Closer to the feet

ex. the hips are inferior to the heart

Lateral

away from the middle of the body

ex. the fingers are lateral to the ribs

Medial

closer to the middle of the body

ex. the heart is medial to the wrist

Proximal

closer to the center of the body or the point where the limb connects

ex. the shoulder is proximal to the elbow

Distal

away from the center of the body or the point where the limb connects

ex. the fingers are distal to the elbow

Deep

away from the outside surface of the body

ex. the ribs are deep to the skin

Superficial

towards the outside surface of the body

ex. the skin is superficial to the lungs

Ipsilateral

on the same side of the body

ex. a left arm injury is ipsilateral to a left leg injury

Contra-lateral

on opposite sides of the body

ex. the rigth hand is contralateral to the left hand

Sagittal Plane

divides the body into left & right portions

• Mid-sagittal divides body into equal left + right portions

Transverse or Horizontal Plane

divide body into superior & inferior portions

Frontal Plane

divides body into anterior and posterior portions

Abdominal Subdivisions

Right Upper Quadrant, Left Upper Quadrant, Right Lower Quadrant, Left Lower Quadrant

Chemistry in A&P

• Body functions depend on cellular function & cellular function results from chemical changes

• All living organism collection of atoms & molecules

• All life forms composed of matter (anything contains mass & occupies space)

Element

a substance that cannot be broken down chemically into any other substance

Atom

A bit of matter that cannot be subdivided any further without losing essential properties

• Organism dies —> atoms recycle

• Atomic Structure = Nucleus with protons & neutrons surrounded by electrons

Proton

positive charged subatomic particles that are located in the nucleus

number of protons distinguishes one element form another

• Atomic number - also equal to number of electrons & protons if net charge 0

Periodic Table

organized by atomic number, 92 naturally occurring elements , >26 made in lab

• Rows correspond to number of electron shells

• Columns left to right, indicate number of electrons in outer shell

• Similarities occur as same number in electron in outer shell = similar bonding

Isotopes

number of neutrons in an aotm can vary independently of number of protons

• Single element can exist in various forms (isotopes) —> depending on number of neutrons it possesses

• Ex. Isotopes of hydrogen = hydrogen, deuterium, tritium

Radioactive Decay

isotopes used in carbon dating —> when heavy carbon breaks down slowly (can figure out how long someone was dead for)

Atomic Mass

Protons & neutrons are nearly equal in mass & weigh more than electrons

Atomic mass scale indicates an atom’s mass relative to mass of other atoms

Weight

derived from gravitational pull on mass

Mass

amount of matter in an atom independent of location & gravity

Hydrogen, Oxygen, Carbon, & Nitrogen

95% of atoms in living organisms

Hydrogen & oxygen are primarily in wter

Nitrogen in protein

Carbon is building block of all living matter

Mineral & Trace Elements

less than 1% & less than .01% —> essential for normal growth & function

25 elements in the human body

Ions

charged atoms

• Atom that loses one or more electrons = positively charged = cations

• Atom that gains or more electrons = negatively charged = anions

Molecule

particle formed when two or more atoms chemically combine (ex. O_2, , N₂ )

Molecular Formula - depict the elements present & number of each atom present in molecule (H₂O)

Compound

particle formed when two or more atoms of different elements chemically combine

Covalent Bonds

share an electron (strongest bond)

• H=single bonds, O=2 bonds, N=3 bonds, C=4 bonds

Octect Rule

atoms are stable when their outer shell is full —> most atoms the outer shell is filled with 8 but hydrogen is filled with 2

Ionic Bonds

an attraction between two oppositely charged ions, forming a compound

Hydrogen bond

an attraction between the slightly positvely charged hydrogen atom of one molecule & the slightly negatively charged atom of another (weakest)

Chemical Reactions

occur when chemical bonds form or break among atoms, ions, or molecules

Reactants - starting materials of a reaction (atoms, ions, & molecules)

Products - substances formed at the end of chemical reactions

Synthesis Reaction

more complex chemical structure is formed (A + B = AB)

Decomposition Reaction

chemical bonds are broken to form a simpler chemical structure (AB —> A + B)

Exchange Reaction

chemical bonds are broken & new bonds formed (AB + CD —> AD + CB)

Reversible Reaction

the products can change back to the reactants (A+B ←→ AB)

Electrolytes Reaction

substances that release ions in water (NaCl —> Na + Cl^-)

Acids Reaction

electrolytes that disassociate to relase hydrogen ions in water (HCl —> H⁺ + Cl^-)

Bases Reaction

substances that release ions that can combine with hydrogen ions (NaOH —> Na⁺ + Cl^-)

Salts Reaction

electrolytes formed by the reaction between an acid & base (HCl + NaOH —> H₂O + NaCl)

pH

the amount of H⁺ in a solution its a measure of its acidity

Acid

greater proportion H+ ions to OH- ions

• H+ very reactive

• Acids can donate H+ to other chemicals

• Stomach acid

Bases

greater proportion OH- to H+ ions

• Low H+, High OH-

• Antacids

• Baking soda, seltzer

Blood pH

can quickly absorb excess H+ to keep solution from being too acidic

can release H+ ions to counteract increases in OH- concentration

normal blood pH is 7.35-7.45

• Homeostasis controls & regulates pH

• buffers chemical reactions

Alkalosis

occurs when blood pH rises to 7.5-7.8

Acidosis

occurs when blood pH lowers to 7.0-7.3 (holding breath)

Organic Molecules

contain C & H

usually larger than inorganic molecules

dissolve in water & organic liquids

carbs, proteins, lipids, & nucleic acids

Inorganic Molecules

generally do not contain C & H

usually smaller than organic molecules

Usually disassociate in water, forming ions

water, oxygen, carbon dioxide, & inorganic salts

Inorganic Substances - Water

Most abundant compound in living material

2/3 the weight of an adult human

Major component of all body fluid

Medium for most metabolic reactions

Important role in transporting chemicals in the body

Absorbs & transport heat

Inorganic Substances - Oxygen

Used by organelles to release energy from nutrients in order to drive cell’s metabolic activities

Inorganic Substances - Carbon Dioxide

waste product released during metabolic reactions

must be removed from the body

Inorganic Salts

Abundant in body fluids

Sources of necessary ions (Na⁺, Cl^- , K⁺ Ca⁺² )

Play important role in metabolism

Properties of Water

Water has unusual properties that make it critical for life:

• High surface tension (pressure applied to water surface)

  • V-shaped H₂O molecules held together by hydrogen bonds

  • Bonds strong enough to give H₂O surface tension

• Cohesion (ex. allows trees to move water from roots to leaves)

• Large heat capacity (heat used to break/reform hydrogen bonds —> water temp doesn’t increase)

• Low density as a solid (ice has max number of hydrogen bonds form —> molecuels spread apart)

  • Liquid water hydrogen bonds constantly break & reform = more density

• Solvent

4 Types of Macromolecules

Carbohydrate, Lipids, Protein, Nucleic Acids

Carbohydrates

Macro-molecules that function as fuel (C, H, O in 2:1 H:CO)

Carbon hydrogen bonds store a lot of energy & easily break down

Monosaccharides

simple sugars (3-7 carbon atoms)

glucose, fructose, & galactose

• Most carbs ultimately converted into glucose

• Blood sugar

• If energy needed than glucose is broken down if not needed then it is stored as glycogen (short term) or fat (long term)

Complex Carbohydrates

Time released energy packets

Disaccharides (sucrose & lactose), Polysaccharides (starch & cellulose)

• Starch - glycogen is “animal starch”

• Cellulose - provide structural support for plants (humans can’t break down)

• Chitin 0 makes up outer-skin of arthropods (humans can’t break down)

Fiber

“roughage” —> colon cancer prevention & reduction

Undigestible by humans

Lipids

store energy for “rainy day”

Lipids are macromolecules with several functions including energy storage

Lipids = hydrophobic

Lipids = non-polar, greasy to touch, significant of energy storage

Composed of C,H,O —> energy stored in many carbon hydrogen bonds

Glycerol head region & fatty acid tails

Contain more stored energy than carbs

Fats including triglycerides common in food (are one type of lipid)

Characterized by long hydrocarbon tials, fats effectively store energy in bonds connecting molecules

3 Types of Lipids

Fat = long term energy storage

Sterols = regulate growth & development

Phospholipids = form the membranes that enclose cells

Saturated Fats

single bond

each carbon in hydrocarbon chain is bound to 2 hydrogen atoms —> solid at room temp

Unsaturated Fats

double bond

at least one carbon is bound to just one hydrogen (double bond) —> liquid at room temp

Cholesterol

used along with phospholipids to build sex hormones & membranes

important components of cell membranes —> can attach to vessel walls & cause them to thicken which may lead to high BP, stroke, & heart attack

Steroid Hormones

regulate sexual development, maturation, & sex cell production

• Estrogen includes memory & mood

• Testosterone stimulates muscle growth (synthetic variation)

Phopholipids

major component of cell membrane (hydrophilic head & hydrophobic tail)

Protein

versatile macromolecules that serve as building blocks (200,000 types)

amino acids - 20 different amino acids strung together make a protein

Protein 3-D Shapes

Primary structure - the sequence of amino acids in a polypeptide chain

Secondary structure - hydrogen bonding between amino acids

• 2 common patterns = twist like a corkscrew & zig-zag folding

Tertiary Structure - folding and bending of the secondary structure due to bonds such as hydrogen bonds or covalent sulfur bonds

Quartnary Structure - two or more polypeptide chains are held together by bonds between the amino acids on different chains (ex. hemoglobin)

Denatured Protein

extreme environment (heat, pH) disrupts protein shapes & function