Physiology Exam 1 Study - Shaughnessy

What is Phisiology?

The study of the normal function of living organisms and their component parts

Form reflects

function

Function reflects

form

Homeostasis

dynamic consistency of the internal environment

Negative feedback

Response counteracts the stimulus, shutting off the response loop

Positive feedback

Response reinforces the stimulus, sending the variable farther from the setpoint

Local control

cells in the vicinity of the change initiate the response

Reflex control

cells at a distant site control the response

Mass balance

existing body load + intake or metabolic production - excretion or metabolic removal

Equilibrium is rare, but

stable disequilibrium is common

What are the four macromolecules?

carbohydrates, lipids, proteins, nucleic acids

Polysaccharides

polymers of simple sugars linked by glycosidic bonds

Digestion uses _______ to break glycosidic bonds

enzymes called glycosidases

Most abundant monosaccharide

glucose

Most abundant polysaccharides

1. Cellulose (cell wall in plants)

2. Chitin (exoskeleton in arthropods)

Amylase

breakdown of starch

Sucrase

breakdown of sucrose

Lactase

breakdown of lactose

Essential means

a necessary nutrient that can be obtained only from the diet

Lipases break

ester bonds that hold fatty acids together

Phospholipids

two lipides, a glycerol unit, and a phosphate group

Proteins

polymers of amino acids

How many amino acids are essential?

eight

Digestion uses ______ to break peptide bonds

enzymes called proteases

Primary protein structure

1D; peptide bonds; sequence of amino acids

Secondary protein structure

2D; hydrogen bonds; helix/sheets

Tertiary protein structure

3D; hydrogen bonds, disulfide bonds; hydrophobic interaction; fibrous proteins, globular proteins

Quaternary protein structure

dimerization; final function unit; hemoglobin

8 protein functions

Structural

Enzymes

Membrane transporters

Signal molecules

Receptors

Binding proteins

Immunoglobulins

Regulatory proteins

Nucleotides

involved in cellular energy and genetic information

Nucleic acids

polymers of DNA or RNA that are linked by phosphodiester bonds

Digestion uses ______ to break phosphodiester bonds

enzymes called nucleases

Vitamins

organic complexes that your cells cannot make

Minerals

ions of elements that your cells cannot make

Vitamins and minerals are obtained through

digestion

Hydrophilic interactions create

biological solutions

_______ dissolves in ______

solutes; solvent

Hydrophilic molecules are

polar and ionic

Hydrophobic molecules are

Nonpolar

Protein and ligand interactions are _____ and _______

Selective, reversible

Cofactors

required for ligand binding at binding site

Proteolytic activation

converts inactive to active form by removing part of molecule

Competitive inhibitor

competes directly with ligand by binding reversibly to active site

Irreversible inhibitor

binds to binding site and cannot be displaced

Allosteric modulator

binds to protein away from binding site and changes activity; may be inhibitors or activators

Covalent modulator

binds covalently to protein and changes its activity

How do pH and temperature affect enzyme activity?

Alter 3D shape of protein by disrupting hydrogen or S-S bonds; may be irreversible if protein becomes denatured

What are the 3 major cavities?

cranial, thoracic, abdominopelvic

What are fluid-filled compartments

Circulatory system

Eyes

Cerebrospinal fluid

Pleural sacs

Pericardial sac

Hollow organs

heart, lungs, intestines, blood vessels

Lumen

interior of any hollow organ

Cell membrane function

Barrier

Exchange

Communication

Secretion

Support

Cell membrane

separates cell from environment

Hydrophilic substances cross

the membrane through channels (regulated transport)

Lipophilic substances cross

the phospholipid bilayer (simple diffusion)

Osmosis

passive movement of solvent across a semi-permeable membrane to equalize concentration of solutes

Reverse osmosis

Forcing water through membranes to filter out osmolytes

Exocytosis

macromolecules exit a cell via a secretory vesicle

Secretory vesicles are produced in

the golgi apparatus

Endocytosis

macromolecules enter a cell via an endocytic vesicle

Endocytic vesicles take material to the _________ for digestion

lysosome

Cytosol

Fluid portion of cytoplasm

Cytosol is comprised of

Ions, small organic molecules, macromolecules

Cytoplasm

the cytosol and all of the organelles, inclusions, and cytoskeleton (not nucleus)

Cytoskeleton functions

cell shape, internal organization, intracellular transport, assembly of cells into tissues, movement

Cilia

moves for surface fluid

Flagella

structure for movement through media

Nucleus

site where DNA is packaged into chromosones; site of transcription

Mitochondria

site of aerobic metabolism

What does the aerobic metabolism produce

ATP

Endoplasmic reticulum

protein synthesis

Ribosome

macromolecular complex of protein and RNA

Golgi apparatus and secretory vesicles

protein modification, packaging, and secretion

Lysosome

site for intracellular digestion; site for breaking down macromolecules

Central dogma

Cells are governed by a cellular chain of command: DNA to RNA to Protein

Histology

study of tissues

Four major tissues

epithelial, connective, muscle, nervous

Cell junctions

gap junctions, tight junctions, anchoring junctions

Gap junctions

communication

Tight junctions

regulate paracellular transport

Anchoring junctions

connect cells

What are the characteristics of epithelial tissue?

Minimal matrix; basal lamina; no direct blood supply; microvilli, cilia; body surface, cavities, tubes, secretory glands; variable layers

Where is epithelial tissue found?

Body surface, cavities, tubes, secretory glands

What are the characteristics of connective tissue?

Extensive matrix; varied; cartilage has no blood supply; cells not in layers

Where is connective tissue found?

Supports skin and organs, cartilage, bone, blood

What are the characteristics of muscle tissue?

Minimal matrix; external lamina; able to generate electrical signals, force, movement; cells linked in sheets or bundles

Where is muscle tissue found?

skeletal muscles, hollow organs, tubes

What are the characteristics of nerve tissue?

Minimal matrix; external lamina; able to generate electrical signals; cells isolated or networked

Where is nerve tissue found?

Throughout body, brain, spinal cord

functions of epithelial tissue

protection, regulation, secretion

5 types of epithelial tissue

exchange, transporting, ciliated, protective, secretory

Exocrine glands

release products to external environment

Endocrin glands

release hormones into extracellular compartments

What is the most abundant tissue?

connective

Functions of connective tissue

support, anchor, or link

Types of muscle tissue

skeletal, cardiac, smooth

Excitable tissues

nervous and muscular tissues

Organs

groups of tissues working in coordination to carry out a function

Organ systems

group of organs working in coordination to carry out a function

Catabolic reactions

break down large chemicals and release energy