Post on 24-Jan-2022
Cardiovascular System (outline)• Review types of tissues• Example of intestines as an organ with all 4 tissue types• Roles of the cardiovascular system & coordination of
other organ systemsAnatomy of the Cardiovascular system of animals• Evolutionary changes• Mammalian heart structures and function
Physiology of the Heart (lab)• Blood Pressure• Heart beat or rhythm• Heart attacks and atherosclerosis
ReviewTissues are groups of many similar cells that
perform the same specific function
Tissue types• Epithelial tissue• Connective• Muscle• Nervous
https://www.youtube.com/watch?v=tKWTJ3_-1E8
An organ is made of several tissues that collectively perform specific functions
Figure 20.9
Small intestine(cut open)
Lumen
Epithelial tissue(columnar epithelium)
Connective tissue
Smooth muscletissue (2 layers)
Connective tissueEpithelial tissue
Lumen
Cardiovascular System
• All cells need– Nutrients– Gas exchange– Removal of wastes
• Diffusion alone is inadequate for large and complex bodies• Most animals use a circulatory system
– Blood: Connective tissue with different cells within a liquid matrix
– Heart: Organ with 4 types of tissue – Blood vessels: Organs with 4 types of tissue
Classifying closed circulatory systems
Section 30.2
Closed circulatory systems are distinguished based on the number of heart chambers.
Figure 30.2
Fishes and larval amphibians Adult amphibians and most nonavian reptiles Birds and mammals
Birds and mammals have a four-chambered heart
Section 30.2
Birds and mammals have a four-chambered heart. Blood is pumped to the lungs and then returns to the heart to be pumped to the rest of the body.
Figure 30.2
Diffusion ofmolecules
Capillary
Interstitialfluid
Tissuecell
https://www.youtube.com/watch?v=q0s-1MC1hcE
A summary of the functions of the Cardiovascular System & coordination with other organ systems
Section 30.2 Table 30.1
TA B L E 30.1 Functions of Blood: A SummaryFunction Explanation
Gas exchange Carries O2 from lungs to tissues; carries CO2 to the lungs to be exhaled
Nutrient transport Carries nutrients absorbed by the digestive system throughout the body
Waste transport Carries urea (a waste product of protein metabolism) to the kidneys for excretion in urine
Hormone transport Carries hormones secreted by endocrine glands
Formation of interstitial fluid Blood plasma leaking out of capillaries becomes interstitial fluid that surrounds cells.
Maintenance of homeostasis (temperature, water, pH)
Absorbs heat and dissipates it at the body's surface; regulates cells' water content; buffers in blood help maintain pH of interstitial fluid and lymph.
Protection Blood clots plug damaged vessels; white blood cells destroy foreign particles and participate in inflammation.
Blood composition
Section 30.2
Blood consists of different cells with diverse functions suspended in a liquid extracellular matrixcalled plasma.
Figure 30.3
©National Cancer Institute/Getty Images
Plasma
Section 30.2
Plasma is mostly water but also contains antibodies and many other dissolved substances.
Plasma carries red blood cells, white blood cells, and platelets.
Figure 30.3
Red blood cells
Section 30.2
Red blood cells carry oxygen to body tissues.
Red blood cells contain hemoglobin, a protein that binds to oxygen at respiratory surfaces and “unloads” oxygen at body tissues.
Figure 30.3
©National Cancer Institute/Getty Images
Blood types
Section 30.2
A person’s blood type depends on what carbohydrates are on the surface of his or her red blood cells.
Figure 10.18
Genotypes PhenotypesSurface molecules ABO blood type
𝐼𝐼𝐴𝐴𝐼𝐼𝐴𝐴
𝐼𝐼𝐴𝐴iOnly A Type A
𝐼𝐼𝐵𝐵𝐼𝐼𝐵𝐵
𝐼𝐼𝐵𝐵iOnly B Type B
𝐼𝐼𝐴𝐴𝐼𝐼𝐵𝐵 Both A and B Type AB
ii None Type O
Agglutination
Section 30.2
The immune system reacts to blood cells with foreign carbohydrates. The foreign blood clumps together in a reaction called agglutination.
Figure 30.4
©Jean Claude Revy - ISM/Phototake
White blood cells
Section 30.2
White blood cells are part of the immune system. They provoke inflammation and destroy microbes, among many other functions.
Figure 30.3
©National Cancer institute/Getty Images
Platelets
Section 30.2
Platelets are cell fragments that initiate blood clotting.
Figure 30.3
©National Cancer Institute/Getty Images
Clotting
Section 30.2
Platelets adhere to each other at a break in a blood vessel. Plasma proteins called clotting factors reinforce the clot.
Figure 30.5
1. Break in vessel wall allows blood to escape; vessel constricts.
2. Platelets adhere to each other, to end of broken vessel, and to exposed collagen. Platelet plug temporarily helps control blood loss.
3. Exposure of blood tosurrounding tissue activates clotting factors. The resulting protein threads trap red blood cells, forming a clot.
(b): ©Steve Gschmeissner/Getty Images RF
Tissues types within the
Cardiovascularsystem and their
function
The cardiovascular system: an overview
Section 30.3
The heart pumps blood through three main types of blood vessels: • Arteries –away
from the heart• Capillaries-
smaller branches of arteries
• Veins – toward the heart
Figure 30.6
The mammalian heart– Two thin-walled atria that pump blood to ventricles– Thick-walled ventricles that pump blood to lungs and all other
body regionsRight atrium To lung
From lung
Semilunarvalve
Atrioventricular(AV) valve
Left atrium
To lung
From lung
Semilunarvalve
Atrioventricular(AV) valve
Rightventricle
LeftventricleBlood Anatomy and Circulation
http://www.youtube.com/watch?v=H04d3rJCLCE 3:29 mins
Flow through the Heart https://www.youtube.com/watch?v=7XaftdE_h607.5 mins
The heart is a muscular pump
Section 30.4
The muscular heart pumps thousands of liters of blood through the body each day.
A thick layer of cardiac muscle called the myocardium makes up most of the wall of the heart.
Figures 25.6, 30.7
Type: Cardiac muscle tissueComposition: Short, branched cells, each containing one nucleus; striated Function: Contraction of atria and ventricles in heart (involuntary) Location: Walls of the heart
The pericardium
Section 30.4
The heart is surrounded by a sac made of dense and loose connective tissue called the pericardium, which anchors the heart but also allows it to beat without being obstructed.
Figure 30.7
The four chambers of the heart
Section 30.4
Blood passes through the four chambers of the human heart.
Figure 30.7
Superiorvena cava
Pulmonary artery
Capillariesof right lung
8
9
2
3
Aorta
4 510
1 6Pulmonary vein
9Right atrium
Inferiorvena cava
Right ventricle
4
8
3
Pulmonary artery
Capillariesof left lung
Aorta
Pulmonary vein
Left atrium
Left ventricle
27
Capillaries of head, chest, andarms
Capillaries of abdominal regionand legs
Blood Pressure
Blood pressure and velocity is a reflection of the heart and blood vessels function in blood circulationRhythmic heart contractions and relaxations
http://www.sumanasinc.com/webcontent/animations/content/bloodpressure.html
Blood pressure – The force blood exerts on vessel walls– Depends on
– Cardiac output– Resistance of vessels
– Decreases as blood moves away from heart Understanding Blood Pressure – Anatomy
http://www.youtube.com/watch?v=qWti317qb_w 2:48 mins
• Blood pressure is – Highest in arteries– Lowest in veins
• Blood pressure is measured as – Systolic pressure—pressure caused by contraction
ventricles– Diastolic Right and left ventricles relax
Lub Dub https://www.youtube.com/watch?v=-4kGMI-qQ3I
Semilunarvalvesclosed1 Heart is
relaxed.
AV valvesare open.
Diastole
0.4 sec
2 Atriacontract.
Systole0.1 sec
Semilunarvalvesare open.
3 Ventriclescontract.
AV valvesclosed
0.3 sec
An internal pacemaker sets the tempo of the heartbeat
The heart contracts and relaxes rhythmically under the effect of electrical signals received from specialized cardiac muscle cells and conducting fibers (not nervous tissue)
• pacemaker (SA node) which generates electrical signals in right atrium
• AV node then relays these signals to the ventricles
Cardiac conduction system and ECG.wmv https://www.youtube.com/watch?v=RYZ4daFwMa8
Schematic illustration of the cardiac conduction system
http://emedicine.medscape.com/article/1922987-overview
Pacemaker(SA node) AV node
Rightatrium
1 Pacemakergeneratessignalsto contract
2 Signals spreadthrough atriaand are delayedat AV node
ECG
3 Signals relayedto apex of heart
4 Signals spreadthroughventricle
Apex
Specializedmuscle fibers
Cardiac Conduction Systemhttp://www.youtube.com/watch?v=Lt092HZCppo 1:03 minshttps://www.youtube.com/watch?v=RYZ4daFwMa8
depolarization of the heart’s atria depolarization
of the heart’s ventricles
Re-polarization of the ventricles
https://www.youtube.com/watch?v=lRHq7sMRWpUhttps://www.youtube.com/watch?v=FThXJUFWUrw
What is a heart attack?• A heart attack is damage to cardiac muscle
typically from a blocked coronary artery• Stroke- Death of brain tissue from blocked
arteries in the head
Blockage
Deadmuscletissue
Right coronaryartery
Superior vena cava
Pulmonary artery
Aorta
Leftcoronaryartery
What is a heart attack?
• Atherosclerosis– Plaques develop inside inner walls of blood vessels– Plaques narrow blood vessels– Blood flow is reduced
PlaqueEpitheliumConnectivetissue
Smoothmuscle