Exam 3

Cardiac System

100

Define Diastole and Systole.

Diastole: Relaxation

Systole: Contraction

200

Define the following: Veins, arteries, and capillaries.

Veins: Carry deoxygenated blood to the heart, Not as strong as arteries.
Arteries: Carry oxygenated blood from the heart to body tissues. Have thicker walls & elastic fibers to withstand pressure. 

Capillaries: Where blood diffusion occurs. Capillaries have the thinnest walls to help with diffusion into tissues. Connects veins and arteries. 

300

How does the heart get blood for its self? 

Through the coronary circulation. It is the most oxygenated.

400

Define the following: AV Node, SA Node, AV Bundle of HIS, Authorythmic Cells. 

AV Node: Located in the atrial septum, it transmits a signal to the Bundle of HIS

SA Node: Cluster of cells in the wall of the right atria. It begins heart activity that spreads to both atria. 

AV Bundle of HIS: Connection between atria and ventricles. It divides into bundle branches and purkinje fibers.

Authorythmic Cells: Cells that fire sponateously, the cell acts as a pacemaker and forms the conduction system for the heart.

500

List the steps to heart circulation? (HINT: Systemic and Pulmonary Circulation)

Deoxygenated blood flows into the right atrium through the tricuspid valve and into the right ventricle. It is pumped through the pulmonary semilunar valve into the pulmonary trunk and the pulmonary arteries carry blood to the lungs for the exchange of gases. Oxygenated blood is brought back to the heart through the pulmonary veins and deposited into the left atrium. It flows through the bicuspid valve into the left ventricle. It gets pumped through the aortic semilunar valve into the aorta and pumped to the rest of the body through the aortic arteries.

Cardiac System 2

100

Which ventricle is the thickest?

Left Ventricle

200

What makes AV and Semilunar Valves open and close?

AV Nodes: Opens when ventricles are relaxed. Close when the ventricles contract

Semilunar Valves: Opens when the ventricles contract. Close when ventricles relax.

300

What is a refractory period? What are the 2 parts?

- When a cell will not respond to any stimulus 

* Relative Refractory Period: On repolarization downslope, Stronger than normal impulse allows AP

*Supernormal Period: Impulse weaker than normal

400

What are the steps of electrical conduction in the heart?

• The SA node depolarizes.
• Electrical activity goes rapidly to the AV node via internodal pathways.
• Depolarization reads more slowly across the atria. Conduction slows through the AV node.
• Depolarization moves rapidly through the ventricular conducting system to the apex of the heart.
• Depolarization wave spread upward from the apex.

500

What is the cardiac cycle and what are the steps?

• The name of the events that occur during one complete heartbeat (both atria and ventricles contract and then relax).

Steps:

• Mid to late diastole: Blood flows from the atria into the ventricles, the atria contract to squeeze the remaining blood into the ventricles.
• Ventricular systole: blood pressure builds before ventricles contract, when ventricles contract pressure is high enough to open semilunar valves which pushes blood to the lungs and body.
• Early diastole- atria finishing refilling. This is when the pressure in the atria is greater than ventriculus and the AV valves will open allowing blood to fill ventricles. After this step, the process starts over again.

Suprise Category (+100 Points)

100

The action potential in excitable cells relies on which two ions moving into and out of the cell membrane?

Sodium and Potassium

200

Parasympathetic stimulation of cardiac muscle would ________ activity. (heart rate)

Decrease

300

Repolarization of a nerve fiber is accomplished by ...

K+ diffusion from inside the cell to outside the cell

400

Which features of the heart allow for cell-to-cell propagation of neural impulses to cause a heartbeat?

Intercalated Discs

500

The area of modified cardiac muscle cells in the cell wall of the right atrium that initiates the heartbeat is _____. 

Sinoatrial Node

Nervous System

100

What is the resting potential?

-70 mV

200

What does a leak channel do?

It allows some potassium to move out of the neuron membrane which creates a change in charge.

300

What is the difference between the two matters of the spinal cord?

Grey: Contains neural cell bodies, unmyelinated axons, and dendrites, Talking site, 

White: Covers grey matter, Contain axons that form ascending and descending tracts, Highway for sensory and motor fibers, Transition site

400

What are the 5 components of a reflex arc?

1. Receptor (skin)

2. Sensory Neuron (sends message to spinal cord)

3. Integrating Center (interneuron)

4. Motor Neuron (sends message to muscle)

5. Effector (skeletal muscle)

500

What is the purpose of Cranial Nerve 1, 2, 3, 7, 8, 9?

1: Olfactory (Smell)

2: Optic (Vision)

3: Oculomotor (Muscles of the eye)

7: Facial

8: Vestibulocochlear 

9: Vagus (Sensations & Secretions of viscera)

Nervous System 2

100

T/ F: Action potentials are all or nothing.

 True

200

What are the different orders of the reflex center?

1st Order: Just spinal cord (knee Jerk)

2nd Order: Brain Stem (breathing, sweating)

3rd Order: Cerebral Cortex (tie shoes)

300

1. Excitatory chemically gated channels move ______ the membrane potential threshold (encouraging the all or nothing process). It uses Na to move towards the threshold. 

Whereas 

2. Inhibitory chemically gated channels move ______ from the membrane potential threshold (discourage the all or nothing process). It uses K to move away from the threshold. 

1. Towards

2. Away

400

The spinal cord contains 2 different types of fibers enclosed in connective tissue. What are those fibers and describe them?

Efferent Fibers: Motor, Carries motor information away from the CNS by sending messages out of the spinal cord through the ventral root to muscles and glands in the body

Afferent Fibers: Sensory, Carries information from sensory receptors of the skin and other organs and enters the spinal cord through the dorsal root

500

What are the structural classifications of neurons? 

Multipolar: Several dendrites & one axon (Most Common)

Bipolar: One main dendrite & One axon

Unipolar: One process only (sensory neurons)