Question | Answer |
pressure within the ___ causes valves to open and close (like the wind) | Heart chambers |
when the ___ are relaxed the pressure is ___ which allows them to easily fill. during this time the ___ are contracting and the valves remain ___ | 1. ventricles 2. low 3. atria 4. open |
The pressure builds up in the ___ as they are filling. this forces the ___ open forcing the blood into the relaxed ventricles. | 1. atria 2. ventricles |
a heart beat sounds through a _____ sounds like a lubb-dupp. this is caused by ___ in the heart tissues when the ___ closes | 1. stethoscope 2. vibration 3. heart |
The ___ is when the ventricles ___ (the valves closing) | 1. lubb 2. contract |
The ___ is when the ventricles ___ | 1. dupp 2. relax |
___ muscle fibers connect in branching ___ | 1. cardiac 2. network |
when any part of that ___ is stimulated it sends an ___ through the whole heart causing it to ___ | 1. network 2. impulse 3. contract |
A mass of merging ___ that function as a unit is called a ___ syncytium. in the heart this is located in the ___ and ___ walls. | 1. cells 2. functional 3. atrial 4. ventricals |
The heart contains specialized muscle ___ that do not contract but start and send ___ throughout the ____( heart muscle) | 1. tissue 2. impulses 3. myocardium |
S-a nodes: A small mass of ___ in the right __ that stimulates the heart to ___ causing both ___ to contract. This activity is rhythmic and is sometimes called a ____. the ___ then travels through the junctional ___ to its next stop. | 1. tissue 2. atrium 3. contract 4. atria 5. pacemaker 6. impulse 7. fibers |
A-V nodes: located in the __ between the __. This serves as a pathway to the bundle of __. it then continues to travel down the septum where it __ off into what is called purkinje __. | 1. septum 2. atria 3. his. 4. branches 5. fibers. |
These fibers project inward to the __ and then continues to the __ of the heart. This then causes the __ to contract and force blood out of the ___ | 1. fibers 2. apex. 3. ventricles 4. ventricles |
Records __changes that occur during the cardiac __. body __ can conduct electrical currents so this can be detected by electrodes that are placed on the __. the wires are hooked to a machine with moving __that is recording the __ between the __ changes. | 1. electrical 2. cycle 3. fluids 4. skin. 5. stylist 6. time 7. electrical |
These different changes are known as ___ | 1. waves |
P waves: when the __ contracts | 1. Atria |
QRS complex: the period between the atria contracting and the __ contracting | 1. Ventricles |
T wave: when the ___ contract. | 1. ventricles |
heart ___ changes to meet the demands of the body. Ex. during __ the muscles and __ require more __ and __ so the heart rate __ | 1. rate 2. exercise 3. heat 4. blood. 5. oxygen. 6. increases |
___ are sent from the medulla oblongata to increase or decrease heart __ | 1. impulses 2. rate |
rising body ___ will increase heart rate | 1. temperature |
low body ___ with decrease heart rate | 1. temperature |
___ and ___ also influence heart action. if __ is high it will slow the heart action. if it is low it may cause an ___ (irregular heart rate). Too much ___ may cause the heart to ___ too hard if it is low, it wont contract enough. | 1. potassium 2. calcium 3. K+ 4. arrhythmia 5. calcium 6. contract |