The Cardiovasuclar System Flashcards
What are the three main components?
- blood
- blood vessels
- heart
What term can be used interchangeably with the cardiovascular system?
Circulatory system
What do cells need?
Oxygen and nutrients
What challenge is solved by having a cardiovascular system?
Diffusion is too slow
What are the functions?
- Transport gases, nutrients, hormones and waste
- regulation: blood regulates PH and body temperature
- protection against blood ????
What are arteries?
Carry blood away from heart, carry high pressure blood
Arterioles
Smaller branches of artists, walls are less thick
Capillaries
One cell thick (epithelium) site of gas exchange by diffusion
Venules
Small veins, transport blood from capillary blood to veins
Veins
Pump blood to heart, have valves, looser so they can expand more
What are the blood vessel layers?
Tunica interna (Endothelium and connective tissue) Tunica intermedia/middle sheath (smooth muscle and connective tissue) thicker in arteries Tunica externa ( connective tissues)
Define precapillar sphincter
Circular muscle that controls blood flow
What is the heart?
A cone shaped muscle organ about the size of a fist
Myocardium
Major portion of the heart that consists if cardiac muscle tissue
Pericardium
A thick serous membrane that secrets a small quantity of lubricating liquid (to prevent friction)
Ventricles
Pump blood to lungs and body
What are the two valves that lay between the atria and the ventricles called?
Atrioventricular valves
What are the strong fibrous strings called in the heart that control the main valves?
Chordae tendineae
What is the pathway of blood through a loop?
leaves heart and pumps to the heart first, then the lungs, brain, and the rest of the body.
How are different vessels specialized?
Veins carry low pressure blood to the heart, and arteries carry high pressure blood away from the heart. Since it has to carry higher pressure blood, the arteries have thicker walls to prevent the vessel from popping.
How do closed and open systems differ?
open systems do not transfer gases.
How do single and double loops differ?
In a double loop, more oxygen can be carried to the body at one time since there are multiple routes for the blood to take.
what are the four properties of cardiac muscle?
Contractile, self-excitable, authorythmic, non-fatiguing.
Describe contractile:
When stimulated to do so, cardiac muscle cells can shorten themselves using motor proteins to contract the entire muscle.
What does depolarization mean?
positive calcium ions are located outside of the cells and negative ions are located inside of the cell. Ion channels open to allow for calcium to flow into the cell, neutralizing the cell.
How does depolarization affect muscles?
Depolarization causes the motor proteins, actin and myosin, to move past each other, generating force and shrinking the cell.
Describe Self-excitable:
Spontaneously open ion channels, one cell may stimulate its neighbour if depolarized ions leak into the neighbouring cell triggering the ion channels to open. (through diffusion)
Define autorhythmic:
start a contraction every 1.5 seconds automatically. Brain controls this rhythm
Define Non-fatiguing:
Can contract indefinitely for a lifetime
What is the sequence of events during a heartbeat?
just do it
How do valves direct blood flow?
They contract towards their final destination
How is the pace of the heart maintained and controlled?
The sinoatrial node, known as the pace maker, is located at the top left corner of the right atrium, and sends out initial signal for all cells to contract. The signal then groups at the atrioventricular node and waits for the atria to stop contracting before sending the signal to the rest of the heart.
How does the ECG reveal what is happening in the heart?
patches are hooked up to the skin above you heart. It tracks the ions in the skin. When there is a change in the skins ions, the pen moves from the horizontal line, making the shape that is usually seen.
Explain how the structure of the heart makes it an efficient pump
explain
explain how the structure and proteins of cardiac muscle contribute to its function
explain
compare heart structures and cardiovascular systems among other animals
explain
Explain how the heart makes an efficient pump
4 chambers, 2 loops
Compare heart structures and cardiovascular systems with humans and other animals
Closed/open circuits and one loop vs 2
Explain everything about the heart beat
- node signals
Valves
Pressure
Flow direction
What are advantages to the double loop?
Blood can carry more oxygen to the body faster
Relate sequence if heart to ECG
P- sinoatrial nose signaling, atria cells contracting
QRS- Av node signaling (Q), ventricle cells depolarize (r-s), when atria repolarization occurs
T- repolarization of the ventricles
Describe the blood plasma
Blood plasma is a liquid tissue that constructs 55% of whole blood
What does blood plasma consist of?
Water, oxygen, glucose, lipids, hormones, amino acids, plasma proteins, vitamins, and red and white blood cells
What are some plasma proteins?
Albumin, antibodies, fibrinogen
What do Albumin do?
Maintain blood volume and pressure, transpor
What do antibodies do?
fight infection
What to Fibrinogen do?
Clot blood around wounds
What does water do in the plasma?
Maintains blood volume and transports molecules
what do Plasma proteins do?
Maintain blood osmotic pressure and pH
What do salts do in the plasma?
Maintain blood osmotic pressure and pH; aid metabolism
What do gases do in the plasma?
Oxygen (Cellular respiration) and Carbon Dioxide (end of product metabolism)
What nutrients are in the plasma?
Lipids, glucose, and amino acids
What do nutrients to in the plasma?
Food for cells
What nitrogenous wastes are found in the plasma?
Urea and Uric Acid
What do nitrogenous wastes do in the plasma?
Excretion by kidneys
What do hormones, vitamins, etc, do in the plasma?
Aid Metabolism
What makes up plasma (percentages)?
Water (90-92%), Proteins (7-8%), and Salts (less than 1%)
What is the source of water?
Absorbed from intestine
What is the source of proteins?
Albumin and Fibrinogen (Liver), antibodies (B lymphocytes)
What is the source of Salts?
absorbed from intestine
What is the source of Gases?
Oxygen (lungs) CO2 (tissues)
What is the source of Nutrients?
Absorbed form intestine
What is the source of Nitrogenous waste?
liver
What are erythrocytes and what do they do?
Red blood cells; transport oxygen and help transport carbon dioxide
Where is the source of red blood cells?
Red bone marrow
What to erythrocytes look like?
7-8um in diameter, bright-red to dark-purple biconcave disks without nuclei
What are leukocytes and what do they do?
White blood cells and fight infection
What is the source of white blood cells?
red bone marrow
What two types of white blood cells are there?
granular and agranular
What are the Granular leukocytes?
Neutrophils, Eosinophils, Basophils
What are the granular leukocytes?
Lymphocytes and monocytes
Describe Neutrophils(40-70%)
10-14um in diameter, spherical cells with multi lobed nuclei, fine pink granules in cytoplasm, phagocytize pathogens
Describe Eosinophils(1-4%)
10-14um in diameter, spherical cells with billowed nuclei, coarse, repp-red, uniformly sized granules in cytoplasm, phagocytize antigen-antibody complexes and allergens
Describe Basophils(01%)
10-12um in diameter, spherical cells with lobed nuclei, large, irregularly shaped, deep-blue granules in the cytoplasm, release histamine, white promotes blood flow to injured tissues
What are the granular leukocytes?
Lymphocytes and monocytes
Describe lymphocytes(20-45%)
5-17um in diameter, spherical cells with large round nuclear, responsible for specific immunity
Describe monocytes(4-8%)
10-24um in diameter, large spherical cells with kidney shaped, round, or lobed nuclei; become macrophages that phagocytize pathogens and cellular debris
What are thrombocytes and what do they do?
platelets that Aid clotting
Describe thrombocytes
2-4um in diameter, disk shaped cell fragments with no nuclei; purple granules in cytoplasm
What is the source of platelets?
Red Bone Marrow
What are the steps of blood clotting?
- Blood vessel is punctured( blood leaves body due to high pressure in vessel)
- Platelets congregate and form a plug
- Platelets and damaged tissue cells release an enzyme called prothrombin activator and calcium which initiates a cascade of enzymatic reactions
- Fibrin threads form and trap red blood cells (scab)
Why are multistep(cascade reaction) efficient?
- more control over entire process, You don’t want clotting to happen all of the time anywhere
- Enzymes can be used again, they aren’t destroyed
- It’s fast! Spreads quickly (branches off)
What do nodes throughout the body do?
- protect against infection
- sites of lymphocyte formation
- found only in mammals and some small birds
What is the lymphatic system?
An extensive network of vessels and nodes that collect lymph from between cells and return it to venous circulation before it enters the hear
How does lymph get back to heart?
- contraction of muscles, alterations of pressure within chest due to breathing and force of gravity
What functions do lymphatic system carry out?
- Recover fluid and nutrients that would be lost in the tissue and wasn’t recovered by blood back to heart
- lymphocytes in nodes fight against disease
What is systolic pressure in blood pressure?
Systole of ventricles (contraction of ventricles)
What is diastolic pressure in blood pressure?
Diastole of ventricles (relaxation of ventricles)
Define Blood pressure:
amount of force applied to a given area of blood vessel wall as the blood flows through
pressure= force/area
How is blood pressure measured?
A sphygmomanometer measures the systolic and diastolic force acting on the wall of an artery, such as the brachial artery
How do you take blood pressure?
- Use cuff to increase pressure on the brachial artery to the point of stopping the flow of blood by closing the artery
- Slowly decrease pressure until the sound of the artery clapping together can be heard (record value)
- small sprits of blood flow through
- systole pressure = the force of ventricles contracting (maximum) - Release more air from cuff until the sound stops, indicating that the artery has opened completely
- diastole pressure of ventricles
How do veins bring blood back to heart against gravity?
- Muscles
- Valves
- Breathing
- Pulse
- Capillaries
- Gravity
Explain how muscles bring blood back to heart against gravity in veins:
- Skeletal muscles contract making veins smaller and increasing pressure
Explain how valves bring blood back to heart against gravity in veins:
- when vein pressure decreases valves close to prevent blood form flowing backwards
Explain how breathing bring blood back to heart against gravity in veins:
- lungs fill with air, squishing veins in that area and increasing pressure
Explain how the pulse bring blood back to heart against gravity in veins:
- Veins and arteries run side by side, when arteries contract they squish veins and increase pressure
Explain how capillaries bring blood back to heart against gravity in veins:
- pressure from capillaries push blood through veins
Explain how gravity bring blood back to heart against gravity in veins:
- for veins above the heart, they can flow back easily due to gravity
What is shock?
Fast movement of blood to all vital organs away from low priority organs
List the organs from high priority to low priority
- heart
- brain
- digestive organs (stomach, liver, intestines)
- kidneys
- reproductive system
- muscles/limbs
How do you control distribution of volume of blood?
- Pre capillary sphincter muscle
2. Vasoconstriction and vasodilation
Explain how the pre capillary sphincter muscle controls blood distribution.
- contracts to reduce blood flow to lower priority tissues
- reduce the amount of nutrients and oxygen being dropped off
Explain how vasoconstriction and vasodilation sphincter muscle controls blood distribution.
- contraction of smooth muscle in arteries reduce blood flow to one area
- relaxation of smooth muscle to increase blood flow to another area
