Organ System Flashcards
Inhaling
Diaphragm - Contracts and moves downwards
Intercostal muscles - Contract, moving the ribs upwards and outwards
Lungs - expand
Pressure inside the chest - Decreases
Movement of air - Moves into the lungs
Exhaling
Diaphragm - Relaxes and moves up Intercostal muscles - Relax, letting the ribs move downwards and inwards Lungs - deflate Pressure inside the chest - Increases Movement of air - Moves out of the lungs
Where are the lungs?
In the thorax (top part of the body)
What is the journey that inhaled air goes on?
The air goes down the trachea, and then down the bronchi (trachea splits into 2 bronchus), then the air goes into smaller tubes called bronchioles and finally into small bags called alveoli which are the site of gas exchange
Gas exchange in the alveoli
The blood passing next to the alveoli has just returned from the rest of the body, so it contains lot’s of CO2 and very little O2. Therefore oxygen diffuses out of the alveolus (high conc) into the blood (low conc) and CO2 diffuses out of the blood (high conc) into the alveoli (low conc)
Gas exchange at body cells
When blood reaches the body cells, oxygen is diffused from the red blood cells (high conc) into the body cells (low conc), and CO2 diffuses out of the body cells (high conc) into the red blood cells (low conc)
Adaptations of alveoli
- Lungs contain millions of tiny air sacs called alveoli, meaning a high SA:V - which means quick diffusion rates
- Alveoli have walls that are 1 cell thick = a short diffusion path therefore easy diffusion
- Alveoli have a constant supply of blood, meaning the concentration gradient is maintained and oxygen is always moving into the blood, or carbon dioxide out.
Function of the circulatory system
The circulatory system transports oxygen and nutrients to every cell in the body, and removes waste like CO2
The circulatory system is a ______ ___________ system
double circulatory
What does it mean to be a double circulatory system?
In the first system: the right ventricle pumps deoxygenated blood to the lungs to take in oxygen and get rid of carbon dioxide, the blood then returns to the heart through the left atrium
In the second system: the left ventricle pumps oxygenated blood around all the other organs of the body, it gives up oxygen and collects carbon dioxide, returning to the heart through the right atrium
Why does the heart have valves
To make sure blood flows in the right direction - they prevent it flowing backwards, they can open and shut
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What happens to blood returning to the heart?
Blood flows into the 2 atria from the vena cava and pulmonary vein. The atria contract, pushing blood into the ventricles, the ventricles contract (the valves shut) and blood is pumped to the lungs and body out of the aorta and pulmonary artery
What are the coronary arteries?
The heart needs energy so that it can pump blood around the body, this means it needs its own oxygenated blood to do aerobic respiration. Arteries called the coronary arteries branch of the aorta and surround the heart, making sure the heart has it’s supply of oxygenated blood.
What are the 3 types of blood vessels and their functions
- Arteries - these carry blood away from the heart
- Capillaries - Involved with the exchange of material at tissues
- Veins - These carry blood to the heart
Specialities of arteries (3)
Arteries carry blood under high pressure,
- artery walls are strong and elastic
- They have thick walls and a small lumen
- They contain thick layers of muscle to make them strong
Arteries branch into…
capillaries
Specialities of capillaries (4)
- Capillaries are tiny
- They carry blood really close to every cell in the body for substance exchange
- They have permeable walls so substances can diffuse in and out
- Their walls are very thin (about 1 cell) = short diffusion path way and an increased rate of diffusion
Capillaries eventually join up to from…
veins
Specialities of veins (2)
- They have a bigger lumen than arteries to help blood flow despite lower pressure
- They have valves to help blood in the right direction, if they travel uphill
What is the resting rate of the heart controlled by?
A group of cells in the right atrium wall act as a pacemaker. They produce small electric impulses which spread to the surrounding muscle tissue causing them to contract
Why is the left side of the heart thicker than the right?
The left ventricle of your heart is larger and thicker than the right ventricle. This is because it has to pump the blood further around the body, and against higher pressure, compared with the right ventricle. Therefore, the left ventricle has more muscle tissue and is stronger
Components of the blood
Plasma, Red Blood Cells, White Blood Cells, Platelets
Plasma
55% of the blood, “watery part of the blood” - 90% water. Helps to carry cells around the body, regulates fluid content as well, during exercise
Contents: RBC + WBC + platelets + CO2 + Urea + Hormones + proteins + Antibodies and Antitoxins
Red Blood Cells
The job of blood cells is to carry oxygen from the lungs to all the cells in the body - 99% of blood cells produced are RBC
- No nucleus to allow for more haemoglobin to be carried
- Biconcave disk shape to easily fit through the capillaries of the body
- Thin cell membrane allows for rapid diffusion
- large surface area due to biconcave shape allow for efficient diffusion due to the high SA:V
- Contains haemoglobin - a protein present in red blood cells, responsible for transporting oxygen from the lungs to cells in the body - binds to oxygen to become oxyhaemoglobin
White Blood Cells
White blood cells defend against infection
- Some can change shape to engulf microorganisms
- others produce antibodies to fight microorganisms and antitoxins to neutralise toxins produced
- They do have a nucleus
Platelets
Platelets help blood clot
- They are small fragments of cells - they have no nucleus
- They help blood clot at a wound to reduce blood less and risk of infection
- Lack of platelets can cause excessive bleeding and bruising
What is coronary heart disease?
It’s when the coronary arteries that supply blood the the heart get blocked up by cholesterol and become narrow so blood flow is restricted. This results in a lack of oxygen to the heart, which can cause a heart attack.
What are stents?
Stents are tubes that are inserted inside arteries They keep them open, making sure blood can pass through the the heart muscles, keeping the heart beating
What’s statin?
A blood thinner medication that can help prevent cholesterol build up
Coronary Heart Bypass?
A surgery which bypass the blocked section of the artery and routes blood flow
Coronary heart disease treatment
- Stents
- Statin
- Coronary heart bypass
- Diet + Lifestyle change (always should be down)
What is cancer?
Uncontrolled cell growth and division resulting in the formation of a tumour
Benign?
Less invasive tumours, grows until there is no more room. Stays put rather than invading other body tissues, isn’t normally dangerous or cancerous
Malignant?
When the tumour grows and spreads to healthy tissues. Cells can break off and spread through the blood steam called metastasis. Malignant tumours are dangerous and cancerous
What are carcinogens?
Chemicals/agents that can cause cancer
What is ionising radiation?
Ionizing radiation is energy with sufficient strength to cause the ejection of an orbital electron from an atom when the radiation is absorbed.
Cancer risk factors - things that increase the chance of developing cancer?
UV radiation, smoking, excessive drinking, genetics, lifestyle and obesity
Cancer treatments?
Radiation therapy, chemotherapy, surgery and immunotherapy
What is a non-communicable disease?
A disease that cannot spread between people or animals and people. They generally last a long time and slowly get worse.
What happens if you eat more food than you need?
The excess is stored as fat
What is obesity?
Excessive fat accumulation that presents a risk to health
What is Type 2 diabetes
When the body doesn’t make enough insulin to control blood sugar levels, or when your cells stop responding to insulin. This leads to multiple health complications with your kidneys, eyesight and more.
Benefits of exercise? (6)
- Decreased risk of Type 2 diabetes
- Increased lung capacity
- Lower blood pressure
- Less body fat
- Reduced risk of Coronary heart disease
- Increased metabolism
What is insulin?
A hormone that’s released by the pancreas into the blood to bring down your blood sugar levels
What is alcohol?
Alcohol is a drug (a depressant) - ethanol
Effect of alcohol? (3)
- Liver cirrhosis
- Liver (and other types) cancer
- Brain damage - memory impairment, psychiatric problems, leading ultimately to death
Symptoms of liver damage? (5)
- Feeling sick
- Weight loss
- Yellowing of the eyes
- Fatigue and confusion
- Can lead to hepatitis - swelling of the liver
What affects can alcohol cause during pregnancy? (4)
- Low birth weight
- Foetal Alcohol Syndrome
- miscarriage
- premature birth
What is Foetal Alcohol Syndrome?
If you drink alcohol during pregnancy you risk causing harm to your baby. Sometimes this can result in mental and physical problems in the baby, called foetal alcohol syndrome. This can occur because alcohol in the mother’s blood passes to her baby through the placenta.
What are characteristics associated with FAS
- Learning + behavioural difficulties
2. Smaller foetus
Chemicals in a cigarette? (3)
- Carbon monoxide
- Nicotine
- Tar
Nicotine?
Nicotine is an addictive drug found in cigarettes
Tar?
Paralyses cilia and makes them anesthetized resulting in them being unable to waft mucus causing a build up of bacteria and infection and inflammation in the throat.
Carbon Monoxide?
It’s a poisonous gas found in tobacco smoke and it binds to haemoglobin, rendering it unable to carry oxygen. This can lead to breathlessness due to oxygen shortage
Health risks of smoking?
Cancer COPD Smokers cough lung diseases emphysema
What is Liver cirrhosis?
Cirrhosis is scarring of the liver caused by long-term liver damage. The scar tissue prevents the liver working properly.
