Systemic vs. Pulmonary Blood Pressure

• Chapter 8 discusses transport in mammals
• Describes the mammalian circulatory system
• Explains the related structures of arteries, arterioles, veins, venules, and capillaries and their functions
• Describes the structure/functions of blood including oxygen and carbon-dioxide transport
• Enables diagrams of blood vessels and blood cells from slides, photomicrographs, or electron micrographs creation
• Explains tissue fluid formation and functions
• Covers the heart's structure/function
• Describes the cardiac cycle and control

Artificial Hearts

• Cardiovascular diseases cause about 18 million deaths worldwide annually
• Cardiovascular relates to the heart/circulatory system
• Medical assistance is available for a failing heart, ranging from drugs to heart surgery
• Heart transplants were the only hope for some patients until recently
• Those needing a new heart outnumber available hearts
• Patients can wait years, many dying before transplant
• Artificial hearts replace a deteriorated heart
• Patients can go home within weeks of the operation
• Artificial hearts aim to keep a patient alive until transplant
• Some patients have lived for almost 5 years with an artificial heart
• Artificial hearts require external energy supply, like a battery in a backpack
• Biomedical engineers are developing longer lasting hearts
• The first artificial hearts were designed for adult men, smaller ones are available for women/children

Transport Systems in Animals

• Most animals are more active than plants, movement requires energy
• Energy for muscle contraction and nerve impulse transmission is attained from glucose/substances through respiration
• Aerobic respiration, requires good supplies of oxygen, is the efficient form of respiration
• Supplying oxygen to respiring tissues is a key function of an animal’s transport system
• Waste products i.e carbon dioxide, are discarded
• Small animals may be able to obtain sufficient oxygen through diffusion, primarily for less active species
• Oxygen diffuses into a jellyfish from the seawater, then to respiring cells
• Carbon dioxide diffuses in the opposite direction
• Each cell obtains adequate oxygen quickly
• Larger animals such as mammals need a transport system
• Transport system distributes oxygen plus removes waste
• Mammals need more oxygen than most animals
• Mammals use respiration to generate heat inside their bodies, to help keep their body temperature constant

Mammalian Circulatory System

• Mammals transport system consists of a pump (heart) and interconnecting tubes (blood vessels)
• Blood always remains inside vessels
• Known as closed blood system
• Blood travels twice through the heart on one complete circuit
• Referred to as double circulation
• Blood is pumped from the left ventricle into the aorta
• Travels to all body parts except the lungs
• Returns to the right side of the heart through the vena cava
• Called the systemic circulation
• The systemic circulation carries blood
• From the heart to all of the body except the gas exchange surface
• Returns blood back to heart
• Blood is then pumped out of the right ventricle into the pulmonary arteries to the lungs
• Ends along the pulmonary veins, returning on the heart's left side
• Referred to as pulmonary circulation
• The pulmonary circulation is the part of circulation
• Carries blood from the heart to the gas exchange surface, then back
• Pressure in the systemic circulation is higher than the pulmonary circulation

Blood Vessels

• Three types of main vessels make up the circulatory system
• Vessels carrying blood away from the heart are arteries
• Vessels carrying blood toward the heart are veins
• Small arteries are called arterioles
• Small veins are called venules
• Arterioles and venules are linked
• Transfer blood close to every cell in the body
• Small vessel are called capillaries
• Arteries are vessels, thick and strong, carrying blood away from the heart at high pressure
• Veins are vessels with relatively thin walls
• Carries low pressure blood back to the heart
• Arteriole are small artery
• Venule is a Small vein
• Capillary delivers oxygen/nutrients to body tissues plus removes waste products

Arteries and Arterioles

• Arteries function is to transport blood swiftly and at high pressure to the tissues
• Artery walls are very strong and elastic
• Arterial pressure is high
• Thickness and composition enables arteries to withstand the pressure
• Arteries and veins have walls are made of three layers
• Consists of:
  • An inner layer
  • Made up of a layer of endothelium consisting of flat cells (squamous epithelium) fitting together.
  • Elastic fibres makes Endothelium very smooth, reducing minimizing friction with moving blood.
• A middle layer containing smooth muscle, collagen, and elastic fibres
• An outer layer containing elastic fibres and collagen

Elastic Arteries

• Relatively large
• Have lot of elastic tissue and little muscle tissue in their walls

Muscular Arteries

• Arteries that are closer to the destination of the blood than elastic arteries
• In the walls is smooth muscle
• Allows Arteries Can constrict and dilate

Capillaries

• Arterioles branch becoming capillaries
• Capillaries transfer blood close to all cells
• Allows the transport of substances between cells and blood
• forms a network throughout body, except the brain, cornea and cartilage
• Sometimes referred to as capillary beds
• Bringing blood close to the cells in the human body of importance
• Diameter is approximately 7 µm
• The same size as a red blood cell
• Walls have singular layer of endothelial cells
• Red blood cells squeeze through a capillary
• It goes as close as 1 µm of the cells
• The gabs in most cells are important by allowing the components to seep through into the spaces between the cells in all the tissues of the body
• Pressure reduces through capillaries, Blood enters with a pressure of 35 mmHg or 4.7kPa
• Pressure is dropped to around 10 mmHg or 1.3 kPa at its end

Veins and Venules

• The capillaries link to form vessels known as venules
• These join and become the veins
• Veins function is is to return blood towards the heart
• Pressure drops to a very low value upon entering the heart
• In humans, pressure approx 5 mmHg or less
• No need for a vessel with thick walls due to law pressure.
• Veins possess three layers like arteries
• Veins’ middle layer is thinner plus has lesser elastic/muscle fibers
• The low blood pressure in veins creates a problem:
  • How to return blood to the heart
• Veins possess half-moon valves/semilunar valves
• Formed due to the endothelium,
• Allow the blood to move towards the heart and not away
• Many veins run with and close to leg muscles

Blood Pressure in the Circulatory System

• Blood is released from the heart at high pressure
• Loses pressure throughout passing arteries, capillaries, venules and veins
• Occurs in systemic and pulmonary systems
• Pressure leaving the heart is much higher

Tissue Fluid

• Blood consists of cells floats in the plasma
• Mostly water, variety of dissolved substances are in blood plasma:
  • Glucose
  • Urea
• Solutes also include plasma proteins, which remain in the blood at all times
• Plasma is the fluid in the blood, carrying numerous of substances
• Plasma proteins different proteins dissolved in blood plasma, with own function/are made in liver
• The plasma leaks from the cells in the same manner as blood flows
• The tissue fluid makes nearly 1 sixth of your body composition in the space between cells
• Referred also as tissue fluid
• Known as almost colorless fluid that fills spaces between the body forms with fluid from blood capillaries
• Known as similar in comparison of blood almost not containing as protein molecules
• Red blood cells are much to big so does not contain some white cells can move around however
• Two opposing forces cause result of volume that leaves tissue liquid
• Forces:
• Blood pressure
• Water moving from Cappily in to tissue in area

Red Blood Cells

• Colour is caused by haemoglobin
• Haemoglobin transports oxygen from lungs to respiring tissues
• The structure of a red blood cells is unusual by consist of properties
  • Red blood cells have biconcave discs
• Dent increases volume ratio
  • Have Very small cells compared with the diameter of
• 40 µm average vs Liver cell no haemoglobin inside the cell is far from the cell membrane
• Red blood cells are flexible enough to move in small space
• Red cells have no cell materials with more room to carry cell
• Do not last always break some new bone marrow is constant
• New ones made and old ones broken down
• Calculating average life cycle of a life body in this cell of days

White Blood Cells

• Made of blood in marrow:
  • Consist of small nucleus to compared
• • Many shape vary in the different types
    • Mostly larger cell types:
• Wide variety is concerned with functions on division
• Phagocytes
• Lymphocytes - Both help destroy micro organisms
  • Can called also - neutrophil
• Cytoplasm of cells lobe
• Macrophages with an antigen 1. Destroy
• Cell fills it
• almost helps in destroy antigens and which carrie
• Structure and functions
• Vessels in can helps of prepare of light under blood flow
• Light will let look high clear blood through cells and lymph’s and high clear

Haemoglobin

• The protein haemoglobin is key to the transport of O2
• The quantity of oxygen which combines with each sample of haemoglobin is then measured
• When given a value with its function
• Can allow it as
• Dissociation

The Bohr shift

• Molecules should transfer with to lungs oxygen should and with easy released
• The oxygen needs and should be with - One group distortion’ slightly. The shape is easier to molecules changed
• Makes easier to molecules combines
• Then helps and allows molecules of the chain
• Haemoglobin and should carried
• Low side as helps it pick to lungs
• Can cause problems with hydrogen
• Remove solution will solve
• This called pressure should carbon to easy relased and help

Control of Heartbeat

• Needs and cardiac to the most area which starts contracts/ relaxes
• Can need oxygen is can for adjust’ transmission from muscle
• Most can be can function parts of heart as parts can called which parts happen
• The best type starts from right direction which best cycle on the area

Comparing blood pressure in systemic and pulmonary circulations in mammals. Systemic circulation has higher pressure, influencing vessel structure. High systemic pressure ensures efficient nutrient and oxygen transport, demanding robust artery walls. Maintaing blood pressure is vital for circulatory system function.