lecture study guide #1

The process of mantaining a relatively stable internal environment

Reverses a change in a controlled condition

the resopnse is directly opposite the inital stimulus.

Strengthen or reinforce a change in one of the bodys controlled conditions

response is in the same direction as the initial stimulus.

-learned resopnse, can be unlearned

when the control comes from "within" the organ

when the control comes from outside the organ of action-

typically from the nervous or endocrine system eg. "thinking abut food"stimulates an increase in stomach muscle contractions

a combination of an epithlial layer and an underlying connective tissue layer

• Areolar CT = Lamina propria
• epithelium varies; tight junctions, goblet cells (mucin)
• eg, respiratory, digestive, reproductive, most of urinary systems
• always wet
• open to exterior
• important for the body's defense against pathogens

• Areolar CT + Mesothelium (simple spuamous epithelium)
• double layered; visceral & Parietal layers w/serous fluid
• eg, pleura, pericardium, peritoneum
• lines body cavity that does not open directly to the exterior

• Heart
• Blood Vessels
• Blood (connective tissue); (RBC's & WBC's, platelets, proteins)

• Heart
• arteries
• arterioles
• capillaries
• venules
• veins
• heart

to and from the body

to and from the lungs

• endocardium
• myocaardium
• epicardium

• fibrous pericardium
• parietal layer of the serous pericardium
• visceral layer of the serous pericardium

internal lining (of the heart) of mucous membrane with endothelial cells (simple squamous epithelium, the endothelium)

the middle layer, of the heart, walls of cardiac muscle with dense irregular connective tissue borders & fetures

acts as the external "skin" of the heart, also cts as the visceral lyer of the serous pericardium

an outer tough dense irregular connective tissue conering, surrounding the serous membrane

areolar connective tissue in contact with the fibrous pericardium, lined with mesothelium, secreting serous fluid

areolar connective tissuein contact with the heart's myocardium, lined with mesothelium, secreting serous fluid, also acts as the hearts epicardium

***Desmosomes & Gap Junctions***

CONTAIN PLAQUE AND CADHERINS THAT EXTENDS INTO THE INTERCELLULAR SPACE TO ATTACH ADJACENT CELLS TOGETHER

STRENGTH WITH "STRETCH" (LIKE VELCRO)

• CONNECT NEIGHBORING CELLS VIA TINY FLUID FILLED TUNNELS CALLED CONNEXONS
• COMMUNICATION OF CELLS WITHIN A TISSUE
• IONS NUTRIENTS WASTE CHEMICAL AND ELECTRICAL SIGNALS TRAVEL THROUGH THE CONNEXONS FROM ONE CELL TO ANOTHER

• Attached to bones of the skeleton by tendons
• have striations
• voluntary-movement or contractions by conscious control
• Ca⁺⁺ stored in large complex sarcoplasmic reticulum
• neurogenic- somatic nervous system

• walls of hollow internal structures (single Unit)
• -blood vessels, airways of lungs, stomach and intestines
• Nonstriated
• usually invoulantary control
• myogenic - with autonomic nervous system innervation
• Ca⁺⁺ from ECF

• Have striations
• Involuntary movement or contraction is not consciously controlled
• intercalated disc unique to cardias muscle tissue w/high densities of desmosomes & gap junctions
• myogenic w/ autonomic nervous system innervation
• Ca⁺⁺ from ECF and sarcoplasmic reticulum

• Conduction system
• -sinoatrial (SA) node
• -Atrioventricular (AV) node
• -Atrioventricular (AV) bundle (Bundle of His)
• -w/ right and left bundle branches
• -Purkinje fibers

• the workhorse cells-no pacemaker potential
• action potential with plateau due to membrane Ca⁺⁺&K⁺ channels opening at the same time
• depolarization lasts approximately as long as contraction
• refractory period basically negates possibility for summation

• record of electrical changes
• -P wave
• -QRS wave
• -T wave
• -P-Q interval, S-T segment, Q-T interval

ATRIAL DEPOLARIZATION

• VENTRICULAR DEPOLARIZATION
• covers atrial repolarization-can be uncovered

VENTRICULAR REPOLARIZATION

time between start of atrial and ventricular excitation (depolarization)

the time of ventricular depolarization

from the beginning fo ventricular depolarization to the end of ventricular repolarization

SV= EDV - ESV

"heart beat"- Lubb & Dupp

• Heart murmurs
• -stenotic valves or incompetant valves