Exam 1 Flashcards
Necessary life functions:
- Maintains boundaries
- Movement
- Responsiveness
- Digestion
- Metabolism
- Excretion
- Reproduction
- Growth
Responsiveness
Ability to sense changes in the environment and respond
Digestion
Breaking down food into molecules that can be absorbed by the bloodstream
Metabolism
Chemical reactions that occur within the body’s cells
Excretion
Process of removing waste from the body
Reproduction
Occurs cellularly and organismally
Homeostasis
Maintaining internal conditions in response to external stimuli
blood sugar example
Involves receptor, control center, and effector
Negative Feedback Loop
Output will shut off original stimulus or reduce the intensity
EX: blood sugar
Positive Feedback Loop
Enhances the original stimulus so that the response it accelerated
EX: childbirth
Matter
Anything that occupies space and has mass
Solids
Definite shape and volume
Liquids
Definite volume but shape takes form of container
Gas
Neither definite shape nor volume`
Electrical Energy
Results from movement of charged particles
Mechanical Energy
Directly involved in moving matter
Radiant Energy
Travels in waves
Chemical Energy
Stored in the bonds of chemical substances
Kinetic Energy
Energy in motion
Potential Energy
Stored energy
Elements that compose the majority of the body:
Oxygen, Carbon, Hydrogen, Nitrogen
What drives electrons in chemical reactions?
Octet Rule: atoms desire 8 electrons in their valence shells
Ionic Bond
Formed by the transfer of one or more electrons from one atom to another
Anion
Atom that gains an electron- negative charge
Cation
Atom that loses an electron- positive charge
Covalent Bond
Formed by the sharing of electrons
-polar: unequal
-nonpolar: equal
Electronegative
Greater electron-attracting capability
Electropositive
Less electron-attracting capability
Hydrogen Bond
Attraction between electropositive hydrogen of one molecule and the electronegative atom of another molecule
Synthesis Reactions
Building things up or combining atoms/molecules
Decompositon Reactions
Breaking down or reducing a larger molecule into simpler molecules
Reduction-Oxidation Reaction
OIL RIG
EX: Cellular respiration
Biochemistry
The study of the chemical composition and reactions of living matter
Inorganic
Chemicals in the body that don’t contain carbon
EX: water, salts, acids and bases
Organic
Molecules unique to living systems that contain carbon
Water properties:
- High heat capacity
- High heat of vaporization
- Polar solvent properties
- Reactivity
- Cushioning
Salts
Contain cations other than Hydrogen and anion other than Hydroxyl; when dissolved in water, they dissociate into their component ions
Salts in body:
Calcium Phosphates are responsible for making bones and teeth hard.
Electrolytes of sodium/potassium are critical for nerve impulses and muscle contractions.
Acids
Substances that release hydrogen ions in detectable amounts
Bases
Substances that take up hydrogen ions in detectable amounts
pH Scale
Neutral= 7
>7 basic
<7 acidic
Buffers
Resist abrupt and large changes in pH
Carbonic Acid-bicarbonate System
When pH rises and blood becomes basic, carbonic acid dissociates to release protons.
When pH drops and blood becomes more acidic, the bicarbonate binds to those protons.
Carbohydrate
Provides ready, easy-to-use sources of fuel
Starch
Storage carbs formed by plants
Glycogen
Storage carbs formed in animal tissues
Triglycerides
Provide the body’s most efficient and compact form of stored energy
Phospholipids
Chief material in building cell membranes
Fibrous Proteins
Structural proteins
Globular Proteins
Functional proteins; unstable
Protein Denaturing
Any shift from “normal” causes the proteins to be outside of their norm and can cause them to unfold and lose their shape, therefore their function
Enzymes
Globular proteins that act as biological catalysts; lower activation energy
Three basic cell parts:
Plasma membrane, cytoplasm, nucleus
Plasma Membrane
Acts as a selectively permeable barrier
Cytoplasm
Intracellular fluid packed with organelles
Nuclues
Controls cellular activities and provides blueprints for protein production
Extracellular Materials:
Interstitial fluid, blood plasma, cerebrospinal fluid
Functions of Plasma Membrane:
- Mechanical barrier
- Selective permeability
- Electrochemical gradient
- Communication
- Cell signaling
Integral Proteins
Firmly inserted into the membrane; function as transport proteins, enzymes, or receptors
Desmosomes
Rivet-like junction formed when linker proteins of neighboring cells interlock like a zipper; allows give between cells
Glycocalyx
Enables cell-to-cell recognition
Peripheral Proteins
Loosely attached to integral proteins; function as enzymes, cell-to-cell connections, motor proteins
Tight Junctions
Integral proteins of adjacent cells fuse to form an impermeable junction that prevents fluids and most molecules from moving in
Gap Junctions
Transmembrane proteins form tunnels that allow small molecules to pass from cell to cell
Chromatin
Arranged in fundamental units of nucleosomes; the unwrapped and uncondensed form of DNA
Histones
A way for the nucleus to pack up the long DNA molecules into a compact and orderly way