Function of circulation

Question 1

What is circulation?

Answer 1

A vascular system (blood vessels) that control movement of fluid (blood) by muscle movement (heart beat) to follow specific pattern

Question 2

What is the main function of circulation?

Answer 2

• Transports gasses (from respiratory), nutrient molecules, waste (from protein digestive, like urea), and hormones (from endocrine system)
• Regulates internal temperature and transport chemical substances from one part of body to another
• Protection against blood loss from injury and against disease-causing microbes/toxic substances introduced into body (WHITE BLOOD CELL)

Question 3

What are the main components of circulatory system?

Answer 3

1. heart
2. blood vessels
3. blood

Question 4

What is the heart?

Answer 4

Muscular organ that pumps blood through body, generate blood flow, move fluid

Question 5

What are blood vessels?

Answer 5

A system of hollow tubes through which blood moves from 1 area to another

Question 6

What is the cardiovascular system?

Answer 6

heart + blood vessel

Question 7

What is blood?

Answer 7

Fluid transport nutrients, oxygen, carbon dioxide, and other materials throughout body → specialized fluid (connective tissue)

Question 8

What is an open circulatory system?

Answer 8

Blood flows freely within body cavity and makes direct contact with organs and tissues → no distinction between blood and interstitial fluid

Question 9

What is a closed circulatory system?

Answer 9

• Keeps blood physically contained within vessels and sep from other body tissues
• Blood follows continuous fixed path of circulation, confining to a network of vessels –> Keep blood sep, from interstitial fluid

Question 10

What does the heart ensure?

Answer 10

healthy heart ensures blood keep flowing in one direction only, and oxygen rich blood is kept separate from oxygen-poor blood

Question 11

What is the structure of the heart

Answer 11

• 4 chambers (top = atrium -> filled with blood returning from body/lungs) (bottom = ventricles -> receive blood from atria and pumps out to body or lungs)
• sep. by septum
• made of cardiac muscle -> allows pump action in heart without it getting tired (contract and relax rhythmically)

Question 12

What is the structure of

Question 13

What is the right side of heart do?

Answer 13

• Right side receives blood coming from body and then pumps to lungs
• 2 large vessels (vena cavae, 1 = vena cava) open into right atrium
• Superior vena cava collects oxygen-poor blood from tissues in head, chest and arms
• Inferior vena cava collects oxygen-poor blood from tissues elsewhere in body
• Oxygen-poor blood flow from right atrium into right ventricle then into the main pulmonary artery→ enters left and right pulmonary arteries (only arteries that contain oxygen-poor blood)
• Continues to left and right lung for gas exchange

Question 14

What does left side of heart do?

Answer 14

• Left side does the reverse, get oxygen-rich blood from left and right lung and pumps blood out of body
• Oxygen-rich flows from lungs through pulmonary veins to left atrium (only ones that contain oxygen-rich blood)
• Left atrium pumps blood into left ventricle → blood goes to body tissues→ leaving through aorta

Question 15

What do valves do?

Answer 15

• Aria and ventricles are separated by valves = atrioventricular valves
• Right side valves is called tricuspid valve → made of 3 flaps
• Left side valves is called semilunar valve→ half moon shape

Question 16

What do blood vessels do?

Answer 16

Arteries: carry blood away from heart, and veins carry blood towards heart
Smaller arteries: are called arterioles
Smaller veins: are venules
- network of capillaries join arteries and arterioles with venules and veins
- 1 cell thick capillaries are sites where gasses, nutrients and other material transfer from blood to tissue cells → then blood

Question 17

What are components of blood vessels?

Answer 17

• arteries
• veins
• capillaries

Question 18

What are the arteries?

Answer 18

Has elastic walls → allowing to expand and wave of blood surges (move quickly forward, sudden) through it during concentration of ventricles → then snap back to relaxation

Question 19

What do arteries do?

Answer 19

• Expansion and contraction of artery walls keeps blood flowing in right direction + allowing extra pumping motion to help blood move through blood vessels
• Feeling heart beat is from the rhythmic expansion and contraction of artery
• Has arterials that CONNECT TO CAPILLARIES

Question 20

What are veins?

Answer 20

Thinner walls than arteries and larger inner circumference

Question 21

How do veins contract?

Answer 21

• Contraction of muscles keep blood in veins flowing towards heart
• Has one way valves that are needed in legs as they ensure blood flows upwards to heart and against gravity
• Has venules that CONNECT TO CAPPRILLIES

Question 22

What are capillaries?

Answer 22

• Smallest blood vessel
• Spread throughout body
• Wall is a single layer cell

Question 23

Needs in circulatory system?

Answer 23

Demands:
- High demand for energy
- Circulatory system must be able to deliver oxygen quickly and in large amounts
- Must carry waste products away from cells quickly

Question 24

How does the circulatory system keep up with high demands?

Answer 24

Oxygen-rich and oxygen-poor blood flow separately → double circulatory system (one circuit between heart and lungs and other is between heart and rest of body)

Question 25

What is pulmonary circulation?

Answer 25

- Movement of blood from heart to lungs → where that blood will carry carbon dioxide gas - After gas exchanges, carbon leaves and oxygen moves to blood - Oxygen-rich blood is brought to heart and goes into the second circuit for transportation to rest of body

Question 26

What is systemic circulation?

Answer 26

- Takes oxygenated blood from heart to body - Blood will return to heart to get waste from body tissues → then goes back to pulmonary circulation

Question 27

What is cardiac circulation?

Answer 27

- Movement of blood through the heart tissues - General movement of pulmonary circulation and systemic circulation (how it comes together)

Question 28

What is blood made of?

Answer 28

Fluid = red blood cell, white blood cell, platelets Solid = plasma

Question 29

What does blood do?

Answer 29

Helps regulate body temp (via hemo), fight pathogen, healing wounds

Question 30

What is the fluid part of blood made from?

Answer 30

Bone marrow

Question 31

What is plasma?

Answer 31

Clear, yellowish fluid - Made of 92% of water, 7% dissolved blood protein, 1% others - Main proteins a) Albumin, globulins and fibrinogen Function: help your body recover from injury, distribute nutrients, remove waste and prevent infection, while moving throughout your circulatory system

Question 32

What are RBC and its function?

Answer 32

- Specialized for oxygen transport (specialized as is a tissue) - Oxygen carrying capacity of blood depend on # of erythrocytes that are present and amount of hemoglobin - A disk-shape cell with no nucleus -> help with more SA - Large amounts of oxygen can be transported in blood as hemoglobin release oxygen in presence of cells - Also transporting some carbon dioxide waste from cells → after it diffuses in blood fluid and some go into hemoglobin

Question 33

What do white blood cells do?

Answer 33

- % in blood may increase to fight infection (can double) has nuclei

Question 34

What are the types of white blood cells?

Answer 34

1. Phagocytes - attack pathogens by eating and destroying them 2. Neutrophils (most abundance) - found in body tissues and blood 3. Basophils - aid in immunity by producing substances that attract phagocytes to destroy pathogens 4. Lymphocytes - produce protein (antibodies) that prevent pathogens of normal function and will easily be detected and destroyed 5. Monocytes - in bloodstream for few days before become specialized as macrophages → destroys bacteria

Question 35

What are platelets?

Answer 35

- membrane-bound fragments of cells, formed from larger cells in bone marrow break - Do not have nuclei and break down within 7-10 days - STOPS YOU FROM BLEEDING

Question 36

Function of platelets?

Answer 36

- Has key role in clotting blood → prevent blood loss 1. When a blood vessel is broken due to injury, it releases chemicals that attract platelets to the site of injury 2. The platelets rupture, releasing chemicals that combine with other chemicals in the plasma to produce the enzyme thromboplastin. 3. As long as calcium ions are present, thromboplastin reacts with prothrombin (a protein made by the liver) to produce another enzyme called thrombin. 4. Thrombin reacts with fibrinogen (another plasma protein) to produce fibrin

Question 37

What does fibrin do?

Answer 37

Fibrin is an insoluble protein that forms a fibrous meat over site of injury → prevent blood loss and will later solidify

Question 38

What is 1 function of blood (#1)?

Answer 38

- Connected to function of digestive system - Blood in capillaries in walls of small intestine absorb nutrients - Blood absorbs nutrient that are made by cells in other systems also - These nutrients (glucose, amino acids) are brought to liver → converted into storage products to be transported to body - Block picks up chemicals and gasses for respiratory system → carries wherever is needed - Blood carries excess amount of mineral ions (end production of proteins) and other waste to kidneys Carries carbon dioxide to lungs

Question 39

What is the function of blood (#2)?

Answer 39

Regulate temp: - balancing loss of heat from body with production of heat - Both vasco and vaso can be triggered by exercising and cause vasodilation to increase blood flow → more oxygen - Countercurrent heat exchange system helps maintain temp - In deep arteries and veins entering and leaving body's extremities lie adjacent to one another → warm blood will exchange heat with cooler blood to return from extremities (limb of a body) (through surface veins or deep veins) to body core to be heated

Question 40

What is vasodilation?

Answer 40

TEMP REGULATION: - To increase blood flow by widening vessels a) Helps body lose heat more rapidly b) When core body becomes too hot c) Release by sweating

Question 41

What is vasoconstriction?

Answer 41

TEMP REGULATION - Decrease in flow of blood by narrowing blood vessels near surface of skin - Help body conserve heat - Waves of muscle contraction → shivering increase production of heat → cellular metabolism