Circulation and BloodCirculation and Blood

Nelson p. 240-279Nelson p. 240-279

Practice SetsPractice Sets

Importance of a Circulatory SystemImportance of a Circulatory System

Read p. 242-243Read p. 242-243

Questions p243 #1-4Questions p243 #1-4 Blood Vessels Read p. 250-253Blood Vessels Read p. 250-253

Questions p.253 #1-4Questions p.253 #1-4 Mammalian Heart Read p. 256-258Mammalian Heart Read p. 256-258

Questions 1-4Questions 1-4

Differentiate between OPEN and Differentiate between OPEN and CLOSED circulatory systemsCLOSED circulatory systems

Closed System – the blood is always contained Closed System – the blood is always contained in either the heart or blood vessels. It never in either the heart or blood vessels. It never leaves them. Example worms, humans, octopusleaves them. Example worms, humans, octopus

Open System – The blood is contained in a Open System – The blood is contained in a heart(s) and blood vessels but at some point is heart(s) and blood vessels but at some point is pumped into the body cavity and bathes the pumped into the body cavity and bathes the cells. This is when the oxygen/nutrients leave cells. This is when the oxygen/nutrients leave the blood and the wastes/carbon dioxide enter the blood and the wastes/carbon dioxide enter the blood.the blood.

Example: snails, lobsters, crabsExample: snails, lobsters, crabs

3. One advantage and one 3. One advantage and one disadvantage of an open systemdisadvantage of an open system

Advantage – does not require a lot of Advantage – does not require a lot of energy to build and repair blood vessels, energy to build and repair blood vessels, create pressurecreate pressure

Disadvantage – blood cannot be directed Disadvantage – blood cannot be directed to specific areasto specific areas

- Limits the size that the organism can grow - Limits the size that the organism can grow toto

4.4.similaritiessimilarities differencesdifferences

SpongeSponge All require All require the delivery the delivery of nutrients of nutrients and and removal of removal of wastewaste

All cells All cells bathed with bathed with fluid fromfluid from

environmentenvironment

No heartNo heart

SnailSnail Open Open systemsystem

Heart Heart presentpresent

EarthwormEarthworm Closed Closed systemsystem

Heart Heart presentpresent

5.5.

MCO’s need a circulatory system to MCO’s need a circulatory system to ensure that nutrients are brought to and ensure that nutrients are brought to and wastes are removed from every cell in the wastes are removed from every cell in the organism including the cells deep within organism including the cells deep within the organisms body.the organisms body.

Blood VesselsBlood Vessels How do arteries differ from veins?How do arteries differ from veins?

ArteriesArteries Carry blood away Carry blood away

from the heartfrom the heart Thick walls made of Thick walls made of

muscle and muscle and connective tissueconnective tissue

Able to stretchAble to stretch

VeinsVeins Carries blood towards Carries blood towards

heartheart Walls made of Walls made of

smooth musclesmooth muscle Blood pressure is Blood pressure is

very low(15-20mmHg)very low(15-20mmHg) Valves prevent blood Valves prevent blood

from flowing from flowing backwardsbackwards

Veins (con’t)Veins (con’t) Muscular contractions Muscular contractions

assist forward assist forward movement of bloodmovement of blood

Reservoir for blood Reservoir for blood (50% of volume)(50% of volume)

What causes a pulse?What causes a pulse?

A pulse occurs when the diameter of the A pulse occurs when the diameter of the artery changes as the heart contracts and artery changes as the heart contracts and relaxesrelaxes

Define vasodilation and vasoconstriction.Define vasodilation and vasoconstriction.

Vasoconstriction Vasoconstriction occurs when a nerve occurs when a nerve impluse causes impluse causes muscle in the muscle in the arterioles to contract arterioles to contract and this reduces the and this reduces the diameter of the blood diameter of the blood vessel and decreases vessel and decreases the flow of blood to the flow of blood to tissuestissues

(become pale)(become pale)

Vasodilation occurs Vasodilation occurs when the muscle in when the muscle in the arterioles relaxes the arterioles relaxes and the diameter of and the diameter of the blood vessel the blood vessel increases and the increases and the flow of blood to the flow of blood to the tissue increasestissue increases

(blushes, release (blushes, release heat)heat)

What are the functions of capillaries?What are the functions of capillaries?

The functions of the capillaries areThe functions of the capillaries are site of gas exchange between blood and site of gas exchange between blood and

cellscells

Practice Set (cont’d)Practice Set (cont’d)

Mammalian Heart Read p. 256-258Mammalian Heart Read p. 256-258 Questions p.258 # 1-4Questions p.258 # 1-4

Components of Blood Read p. 244-246Components of Blood Read p. 244-246 Practice p. 246 #1-8Practice p. 246 #1-8

The Mammalian HeartThe Mammalian HeartWhat is the function of the AV valves and the semilunar valves?What is the function of the AV valves and the semilunar valves?

Ensure the one-way flow of blood Ensure the one-way flow of blood throughout the circulatory systemthroughout the circulatory system

What is angina and what causes it?What is angina and what causes it?

Coronary circulation includes the blood Coronary circulation includes the blood vessels which supply the heart muscles vessels which supply the heart muscles with oxygen and nutrients.with oxygen and nutrients.

AnginaAngina occurs when a coronary artery is occurs when a coronary artery is

blocked and not enough oxygen can get to blocked and not enough oxygen can get to the heart. It caused chest pains and maythe heart. It caused chest pains and may

lead to heart attacklead to heart attack

What are coronary bypass operations and why are they performed?What are coronary bypass operations and why are they performed?

A coronary bypass operation involves A coronary bypass operation involves replacing a coronary artery blocked by fat replacing a coronary artery blocked by fat and plaque deposits with a vein removed and plaque deposits with a vein removed from another part of the patient’s bodyfrom another part of the patient’s body

Differentiate between the systemic circulatory system and the Differentiate between the systemic circulatory system and the pulmonary circulatory system.pulmonary circulatory system.

Components of BloodComponents of BloodWhy is blood considered to be a tissueWhy is blood considered to be a tissue

Blood is considered to be a tissue Blood is considered to be a tissue because it is made of several types because it is made of several types of cells which work together for a of cells which work together for a common purposecommon purpose

2.2. Name the two major components of blood.Name the two major components of blood.

1. plasma –1. plasma –

2. blood cells -2. blood cells -

List three plasma proteins and indicate the function of each.List three plasma proteins and indicate the function of each.

Plasma ProteinsPlasma Proteins

1. Albumins – maintain osmotic 1. Albumins – maintain osmotic pressure (water balance)pressure (water balance)

2. globulins – help protect against 2. globulins – help protect against invading microbesinvading microbes

3. fibrinogens – role in clotting of 3. fibrinogens – role in clotting of bloodblood

4. What is haemoglobin?4. What is haemoglobin?

Haemoglobin is a molecule Haemoglobin is a molecule containing an iron pigment molecule containing an iron pigment molecule in a protein molecule.in a protein molecule.

It’s function is to increase the ability It’s function is to increase the ability of blood to carry oxygen (X70)of blood to carry oxygen (X70)

What is anemia?What is anemia?

Anemia is an illnes caused by a lack Anemia is an illnes caused by a lack of red blood cells. of red blood cells.

It’s symptom is extreme fatigue It’s symptom is extreme fatigue (tiredness) and is sometimes caused (tiredness) and is sometimes caused by too little iron in the diet.by too little iron in the diet.

What causes the production of pus?What causes the production of pus?

Pus is produced from the fragments Pus is produced from the fragments of used white blood cellsof used white blood cells

What is the role of platelets?What is the role of platelets?

The role of platelets is to initiate The role of platelets is to initiate (start) the blood-clotting reponse to (start) the blood-clotting reponse to and injury.and injury.