The heart and blood vessels (Health and disease)

• An organ that pumps blood around the body in a double circulatory system. Blood enters the right and left atrium and the atria contrasts which forces blood into the ventricle and it contrasts and forces it out ( right to the lungs where gas exchange takes place and left to the body)

• Four chambers(left atrium, right atrium, left ventricle, right ventricle, valves)

NOTE: LOOK AT THE LEFT AND RIGHT LIKE YOU ARE LOOKING AT A PERSON

Structure of the heart

• coronary artery- branch out of the aorta to the muscle of heart providing oxygen for respiration which gives it energy for contraction

• The vena cava- blood goes through the vena cava into the right atrium

• The pulmonary artery- is where the blood flows out of the heart to the lungs

• The pulmonary veins- is where blood flows through to the left atrium into the heart

• Aorta- blood flows out through the aorta to the rest of the body

• Valves- between the atriums and ventricles; prevents back flow of blood

NITE: left side has a thicker muscle wall because it needs to provide a lot of energy to force the blood to the rest of the body

Function and structure of each blood vessel

It’s a group of cells that controls the natural resting heart rate; located in the right atrium

Function and location of the pacemaker

Are electrical devices used to correct any irregularities in the heart rate

What’s an artificial pacemaker

• Artery: has a thicker wall and small linen to transport the flow of high pressurised blood to the rest of Body

  • blood in the arteries travel in surges every time the heart beats

• The vein: has a less thick wall but wider lumen to transport the flow of low pressurised blood into the body

  • contains valves

• The capillaries: located around the lungs; consists of red blood cells which contains haemogoblin

  • allows diffusion of oxygen, glucose and waste products

  • Thin cell walls

How does the structure of the three blood vessels relate to their functions

22400 divided by 4= 5600ml/min

5600 times 60= 336000 ml/hr or 336 L/hr

At rest, about 22,400ml of blood flows through the aorta every 4 mins. Calculate the hourly rate of blood flow through the aorta

Blood flow divided by time

Equations for calculating rate of blood flow

• when breathing, oxygen goes through the trachea ( rings of cartilage to prevent collapsing during inhalation)

• Into the bronchi and subdivides to the bronchioles which connects to tiny air sacs called the alveoli(microscopic )is the site of gas exchange

Structure of the lungs

• alveoli causes the lungs to have a huge surface area

• Thin cell walls for rapid diffusion

• When oxygen is diffused into the bloodstream, it’s rapidly removed which shows the concentration gradient is steep

• Good blood supply

This adaptations means that oxygen diffuses into the bloodstream rapidly and CO2 diffuses into the air rapidly

How are the lungs adapted for gas exchange

When breathing fresh oxygen is taken into the alveoli and CO2 which means the concentration gradient will be high and that increases its rate of diffusion

How does breathing increase the rate of diffusion in the lungs

Blood is a tissue consisting of plasma in which the white blood cells, red blood cells and platelets are suspended

define blood

• transports carbon dioxide( produced during aerobic respiration) from the body to the lungs to be breathed out

• It transports waste(urea) from the liver tot the kidney to be excreted as urine

• Transports soluble digestion products (glucose) from the small intestine to other organs

• They carry antibodies, antitoxins, hormones, nutrients, protein and waste products

Functions of plasma

Function- carries oxygen from the lungs to other organs

• Adaptations

  • biconcave disk which provides a large surface area for oxygen

  • No nucleus which means more space haemoglobin

  • Contains haemoglobin that carries the oxygen to the organs from the lungs( when it carries oxygen it becomes oxyhaemoglobin)

Functions and adaptations of the red blood cells

• They engulf pathogens (phagocytosis)

• They produce antitoxins

• They produce antibodies

• They contain nucleus that contains the DNA to provide instructions for it to do its job

Functions of the white blood cells

Tiny fragments of the cell that helps the blood to clot

They stop bleeding

Stop microorganisms from getting into open wound

Functions of platelets

Identify the types of blood cells

• single cell thick( allows diffusion)

• Permeable

• Small lumen to allow

• to diffuse nutrients

How does the structure of capillaries relates to its functions

Layers of fatty materials builds up inside the coronary arteries, narrowing them. This reduces the flow of blood In the coronary artery causing lack of oxygen in the heart muscle

Explain coronary heart disease

• stents are used to kept the coronary arteries open

• Statins are used to reduce the blood cholesterol levels which slows down the rate of fatty materials deposit

Uses of stents and statins

• Both requires surgery which could cause infections

• Both could cause blood clotting

  Mechanical- last a long time

  Biological- wouldn’t last a long time

disadvantages of mechanical and biological valves

Adv of stents

• surgery is quick

• Lasts a long time

  disadvantages

• Could cause blood clot

• Could cause infections

  Advantages of statins

• Reduces bad cholesterol and increases good cholesterol

• Avoids other cardiovascular diseases

Disadvantages

• could cause side effects(kidney failure)

• Needs to be taken regularly

Advantages and disadvantages of stents and statins

Biological heart transplant

Disadvantages

• might take a long time to find a heart donor

• Immune system might reject

  Artificial heart

• Might cause blood clothing

• They aren’t long-term

  Advantages

• Allows real heart to rest as an aid to recovery

• To keep patients alive whilst awaiting heart transplant

• Wont be rejected by immune system

Disadvantages and Advantages of heart transplant

Is the state of physical and mental wellbeing

What’s health

They are most likely to suffer from infectious diseases

What happens if a person has a defect in their human system

Cancer

What does virus living in cells trigggers

When the immune system tries to hard to fight off against pathogens it damages tissues in the process could cause allergies such as asthma and skin rashes

How are allergies caused

Several physical ill health could lead to depression, chronic anxiety and other mental illness

How does health link to mental well-being

Parasites, fungi, bacteria and viruses

How can communicable diseases be spread

HPV- causes cervical cancer

List a type of disease that may cause another disease

• communicable Disease

• Non communicable Diseases

• Stress

• Poor diet

• Life situations

Factors that causes ill health

• A diet high in fat but low in vegetables increase the level of certain types of cholesterol in the blood and increases the rate of fatty materials building up in the coronary arteries

• A diet high in salt increases blood pressure

Effects of bad diet

• Carcinogens causes lung cancer

• Lease to emphysema causes a low quality of life

• Smoking when pregnant causes miscarriage and low body mass

Effects of smoking

• when pregnant could cause fatal alcohol syndrome( physical disabilities and other mental problems )

• In adults, causes liver cirrhosis and cancer

  Mentally;

• Addiction

• Memory loss

Effects of alcohol

Alcohol causes obesity which causes type 2 diabetes

Link between obesity type 2 diabetes and alcohol

A radioactive gas that increases the risk of lung cancer

What’s radon

• carcinogens

• Ionising radiation

Risk factors of cancer

As the number of cigarettes smoked per day increases, the risks for developing lung cancer also increase. positive correlation

Describe this graph

No

Does correlation prove cause

• it means that smoking increases the risks of lung cancer

What does scientist mean when they say that smoking is a causal mechanism for lung cancer

To prevent bias in sampling it’s better to take as random and large number of sample as possible

How to prevent bias in sampling

Sampling might be systematic in that it is carried out at regular time intervals. When working with samples of human populations, studies must take account of possible variations owing to differences: between the sexes. resulting from people of different ages taking part.

Principles of sampling