Circulatory System – Old Year Questions

• The heart rate is the speed of the heart beats, which is measured by counting how many times the heart contracts in one minute.
• Under normal conditions, the heart usually beats 72-75 times a minute. During sleep, the heart rate normally slows down to 40-50 beats per minute.
• The cardiac cycle describes the full heartbeat from the beginning of one beat to the start of the next. This frequency is usually measured in beats per minute (BPM).

• The heart muscles squeeze and relax with each heartbeat. When they squeeze, the heart pumps blood out.
• When they relax, the heart draws blood in. Then it takes a break before squeezing and relaxing again.

• Heart failure and heart disease have different signs for different people, especially for women.
• A heart attack is called a myocardial infarction. Symptoms of a heart attack include pain or discomfort in arms, back, neck, jaws or stomach; shortness of breath with or without chest pain; sweating, nausea or feeling faint.
• Both men and women commonly experience chest pain or discomfort as a symptom of a heart attack.

• Heart failure and heart disease have different signs for different people, especially for women.
• A heart attack is called a myocardial infarction. Symptoms of a heart attack include pain or discomfort in arms, back, neck, jaws or stomach; shortness of breath with or without chest pain; sweating, nausea or feeling faint.
• Both men and women commonly experience chest pain or discomfort as a symptom of a heart attack.

• The human heart is divided into four parts: the left and right atria (upper chambers) and the left and right ventricles (lower chambers).
• Usually, the right atria and ventricles are called the right heart and the left atria and ventricles are called the left heart.
• In a healthy heart, blood is only allowed to flow in one direction through the heart because of heart valves that stop it from flowing backwards.

• The sinus node is an electrical impulse generator that sends signals from the right atrium, just like a pacemaker, to control the heart’s beat.
• These signals travel through the heart, making the chambers squeeze and relax in a regular pattern that pumps blood into and out of the heart.

• Pulse rate is how fast our heart is beating. We measure it in beats per minute (bpm).
• We can use a pulse rate chart to see how healthy our heart is and how fit we are.

• Blood is a type of tissue that is made up of a liquid, called plasma, and other components.
• A normal adult human who weighs 70 kg has about 5-6 litres of blood.

• Blood is a type of tissue that is made up of a liquid, called plasma, and other components.
• A normal adult human who weighs 70 kg has about 5-6 litres of blood.

• Blood is a type of tissue made up of a liquid called plasma and no fibers.
• It moves through the blood vessels and is a thick and sticky fluid.
• Its purpose is to carry oxygen from the lungs to the body’s tissues and then carry carbon dioxide from the tissues back to the lungs.

• Red blood cells (RBCs) help the blood move around the body.
• They have haemoglobin, which is a protein that makes the blood red and lets it carry oxygen from the lungs to the cells.
• The oxygen is used by the cells to produce energy and it makes carbon dioxide as a waste product. RBCs also take the carbon dioxide away from the cells and back to the lungs.

• Haemoglobin is a protein found in red blood cells. It helps transport oxygen from the lungs to the body’s tissues and takes carbon dioxide back to the lungs from the tissues.

• Haemoglobin is a red, iron-containing protein found in red blood cells.
• It transports oxygen from the lungs to the cells and carries carbon dioxide away from the tissues to the lungs.
• A healthy person has 12-16 grams of haemoglobin in every 100 milliliters of blood. The pH of the haemoglobin solution is slightly alkaline, not acidic, and is between 7.1 to 7.4.

• Red blood cells (RBCs) or red blood corpuscles, also known as erythrocytes, are the most common type of blood cell.
• They carry oxygen (O2) to the body’s tissues by flowing through the circulatory system.
• RBCs pick up oxygen in the lungs or gills and then release it when they flow through the body’s tiny blood vessels.
• The inside of the cells is very rich in haemoglobin, an iron-containing compound that can hold oxygen and makes the cells look red.

• Red blood cells (RBCs) or red blood corpuscles, also known as erythrocytes, are the most common type of blood cell.
• They carry oxygen (O2) to the body’s tissues by flowing through the circulatory system.
• RBCs pick up oxygen in the lungs or gills and then release it when they flow through the body’s tiny blood vessels.
• The inside of the cells is very rich in haemoglobin, an iron-containing compound that can hold oxygen and makes the cells look red.

• Red blood cells (RBCs) or red blood corpuscles, also known as erythrocytes, are the most common type of blood cell.
• They carry oxygen (O2) to the body’s tissues by flowing through the circulatory system.
• RBCs pick up oxygen in the lungs or gills and then release it when they flow through the body’s tiny blood vessels.
• The inside of the cells is very rich in haemoglobin, an iron-containing compound that can hold oxygen and makes the cells look red.

• Myoglobin (Mb) is a protein in the skeletal muscles of most mammals that binds oxygen and contains iron (Fe).
• It is similar to haemoglobin, but it binds to oxygen more tightly and does not bind to oxygen cooperatively like haemoglobin.

• Myoglobin (Mb) is a protein in the skeletal muscles of most mammals that binds oxygen and contains iron (Fe).
• It is similar to haemoglobin, but it binds to oxygen more tightly and does not bind to oxygen cooperatively like haemoglobin.

• Earthworms are animals that belong to the Annelida phylum. The blood inside an earthworm contains the molecule haemoglobin and is kept inside special blood vessels.
• This is called a closed circulatory system, which ensures that the blood is kept re-circulating to get the most out of it.

• Red blood cells, or erythrocytes, found in the blood of vertebrates have a red color because of the combination of a protein called hemoglobin and oxygen. These cells don’t have a nucleus.

• Red blood cells, or erythrocytes, found in the blood of vertebrates have a red color because of the combination of a protein called hemoglobin and oxygen. These cells don’t have a nucleus.

• Blood is important in the body for many reasons. It carries oxygen to the cells in the body (attached to a protein called haemoglobin, stored in red cells).
• It also carries nutrients such as glucose, amino acids and fatty acids (either dissolved in the blood or held by proteins in the plasma).

• The typical blood pressure for a person is 120/80 mm Hg. This means the systolic pressure should be about 120 mm Hg and the diastolic pressure should be around 80 mm Hg.

• The typical blood pressure for a person is 120/80 mm Hg. This means the systolic pressure should be about 120 mm Hg and the diastolic pressure should be around 80 mm Hg.

• A Sphygmomanometer is a tool used to measure a person’s blood pressure. It includes an inflatable cuff and a mercury or mechanical manometer.
• It is used together with something that can tell when the blood flow starts and when it flows freely. When using a manual Sphygmomanometer, a stethoscope must also be used.

• A Sphygmomanometer is a tool used to measure a person’s blood pressure. It includes an inflatable cuff and a mercury or mechanical manometer.
• It is used together with something that can tell when the blood flow starts and when it flows freely. When using a manual Sphygmomanometer, a stethoscope must also be used.

• The symbol ‘Hg’ stands for Mercury, a chemical element. This element is used in various items such as thermometers, barometers, and sphygmomanometers.
• A sphygmomanometer is a device that is used to measure blood pressure in millimeters of Mercury (mmHg). Generally, a healthy person’s blood pressure should be 120/80

• The exact source of high blood pressure is unknown, but there are several things that can contribute to it, such as smoking, being overweight, not being active, eating too much salt, drinking too much alcohol (more than 1-2 drinks per day), stress, increasing age, genetics, family history of high blood pressure, chronic kidney disease, and adrenal and thyroid issues.

• Mr. Y’s blood pressure is normal since normal blood pressure in people is usually 120/80, which means the systolic pressure is 120 and the diastolic pressure is 80.
• Mrs. X’s blood pressure is lower than normal, but the other people have higher than normal blood pressure.

• The regular air pressure is 760 mm of mercury. However, the typical human blood pressure is usually around 120/80 mmHg.
• When a doctor measures our blood pressure, it is in relation to the atmospheric pressure.
• This means our blood pressure is 120mm Hg higher than the atmospheric pressure.
• On the other hand, atmospheric pressure is measured in comparison to a vacuum, so our actual blood pressure is 880 mm Hg when compared to a vacuum.

• Karl Landsteiner was a scientist and doctor from Austria. He is remembered for discovering the main blood types in 1900, and creating a way to organize them.
• He also helped figure out the Rhesus Factor, a type of antigen found in monkeys, with Alexander Wiener in 1937. This made it safer to give blood transfusions to people.

• Karl Landsteiner was a scientist and doctor from Austria. He is remembered for discovering the main blood types in 1900, and creating a way to organize them.
• He also helped figure out the Rhesus Factor, a type of antigen found in monkeys, with Alexander Wiener in 1937. This made it safer to give blood transfusions to people.

• People with blood type O can donate to anyone because their red blood cells don’t have either A or B antigens on them.
• This means that their blood can be used for people with any blood type.

• People with blood type O can donate to anyone because their red blood cells don’t have either A or B antigens on them.
• This means that their blood can be used for people with any blood type.

• People with blood type O can donate to anyone because their red blood cells don’t have either A or B antigens on them.
• This means that their blood can be used for people with any blood type.

• People with blood type AB have both A and B antigens on their red blood cells. Their blood does not have any antibodies.
• This means that they can get blood from any group (with AB being the best option), but they can only donate blood to group AB. They are called universal recipients.

• People with blood type AB have both A and B antigens on their red blood cells. Their blood does not have any antibodies.
• This means that they can get blood from any group (with AB being the best option), but they can only donate blood to group AB. They are called universal recipients.

• People with blood type AB have both A and B antigens on their red blood cells. Their blood does not have any antibodies.
• This means that they can get blood from any group (with AB being the best option), but they can only donate blood to group AB. They are called universal recipients.

• People with blood type A have A antigens on their red blood cells and IgM antibodies in their blood that are against the B antigen.
• This means that people with type A can only receive blood from people with type A or O (A is preferable) and can donate blood to people with type A or AB.

• There are four main blood groups defined by ABO system.

1. Blood group A – has A antigens on the RBC with anti-B antibodies in the plasma.
2. Blood group B – has B antigens with anti-A antibodies in the plasma.
3. Blood group AB – has both A and B antigens, but no antibodies.
4. Blood group O – has no antigens, but both anti-A and anti-B antibodies in the plasma.

Red blood cells sometimes have another antigen, a protein known as RhD antigen. If this is present, the blood group is RhD-positive. If it is absent, the blood group is RhD-negative. In most cases, ORhD-negative blood (O–) can safely be given to anyone. It is often used in medical emergencies when the
blood type isn’t immediately known. It’s safe for most users because it doesn’t have any A, B or RhD antigens on the surface of the blood cells, and is compatible with every other A,B,O and RhD blood group.

• There are four main blood groups defined by ABO system.

1. Blood group A – has A antigens on the RBC with anti-B antibodies in the plasma.
2. Blood group B – has B antigens with anti-A antibodies in the plasma.
3. Blood group AB – has both A and B antigens, but no antibodies.
4. Blood group O – has no antigens, but both anti-A and anti-B antibodies in the plasma.

Red blood cells sometimes have another antigen, a protein known as RhD antigen. If this is present, the blood group is RhD-positive. If it is absent, the blood group is RhD-negative. In most cases, ORhD-negative blood (O–) can safely be given to anyone. It is often used in medical emergencies when the
blood type isn’t immediately known. It’s safe for most users because it doesn’t have any A, B or RhD antigens on the surface of the blood cells, and is compatible with every other A,B,O and RhD blood group.

• The couple, who have blood groups AB+ and O–, had twin boys with blood groups A+ and B+. The adopted son has a blood group of O+.

• Bernstein discovered in 1924 that humans have three different blood groups – A, B and O – which are passed down from parents in a pattern following Mendel’s laws.
• If the father has blood group A and the mother has blood group O, the son’s blood group will be either O or A.

• Erythroblastosis fetalis, also called hemolytic anemia, is a severe health problem that often happens when the mother and father have different Rh blood types.
• If the mother is Rh-negative and the father is Rh-positive, the baby can be Rh-positive too.
• This can result in Rh incompatibility and pregnancy problems, and may cause the infant to have serious anemia and other issues.

• The pH level of human blood is usually around 7.4. It is important for the pH level to stay between 7.35 and 7.45, which is slightly basic or alkaline.
• If the pH is lower than 7, the blood is considered acidic. If it is above 7.45, it is too basic.

• The pH level of human blood is usually around 7.4. It is important for the pH level to stay between 7.35 and 7.45, which is slightly basic or alkaline.
• If the pH is lower than 7, the blood is considered acidic. If it is above 7.45, it is too basic.

• The pH level of human blood is usually around 7.4. It is important for the pH level to stay between 7.35 and 7.45, which is slightly basic or alkaline.
• If the pH is lower than 7, the blood is considered acidic. If it is above 7.45, it is too basic.

• Antigens are usually foreign protein molecules, or sometimes polysaccharides, that enter an animal’s body fluids from an infection.
• Antibodies, which are protein molecules in the blood, are created by the animal in response to the antigen.
• This response is called the immune response and can make the animal immune to the foreign antigen.

• Antigens are usually foreign protein molecules, or sometimes polysaccharides, that enter an animal’s body fluids from an infection.
• Antibodies, which are protein molecules in the blood, are created by the animal in response to the antigen.
• This response is called the immune response and can make the animal immune to the foreign antigen.

• Antigens are usually foreign protein molecules, or sometimes polysaccharides, that enter an animal’s body fluids from an infection.
• Antibodies, which are protein molecules in the blood, are created by the animal in response to the antigen.
• This response is called the immune response and can make the animal immune to the foreign antigen.

• White blood cells are cells found in the blood that help fight off disease. If there is any bacteria or virus in the blood, these cells will go to that area and get rid of the bad things.

• White blood cells are cells found in the blood that help fight off disease. If there is any bacteria or virus in the blood, these cells will go to that area and get rid of the bad things.

• Lymphocytes are tiny white blood cells with big nuclei. They make up around 20-25% of all white blood cells, and act like an army to protect the body by working together with other parts of the immune system.
• The three main kinds of lymphocytes are natural killer cells, T cells, and B cells, which play a major role in defending the body against harmful substances.
• They produce antibodies in the blood plasma to help inactivate poisonous substances.

• Lymphocytes are tiny white blood cells with big nuclei. They make up around 20-25% of all white blood cells, and act like an army to protect the body by working together with other parts of the immune system.
• The three main kinds of lymphocytes are natural killer cells, T cells, and B cells, which play a major role in defending the body against harmful substances.
• They produce antibodies in the blood plasma to help inactivate poisonous substances.

• Blood viscosity is mainly determined by the amount of red blood cells (hematocrit) and the thickness of the plasma.
• The thickness of the plasma is affected by how much water it contains and what types of proteins are in it.
• This means that the protein concentration and types of proteins in the plasma affect blood

• The amount of white blood cells (WBCs) in your blood can show if you have a sickness.
• In a healthy adult, the normal amount of WBCs is between 4,000-11,000 per tiny amount of blood.
• This makes up around 1% of the total amount of blood. If the amount of WBCs is higher than the normal range, it is called leukocytosis.
• If it is lower than the normal range, it is called leukopenia. The size of a WBC in a human

• Leukemia is a type of cancer that typically starts in the bones and causes too many strange white blood cells.
• These white blood cells are not mature and are called “blasts” or “leukemia cells”. Signs may be seen, like bleeding and bruising.

• Erythropoiesis is the process in which new red blood cells are made. It usually takes about a week.
• In adults, these cells are produced in the red bone marrow of big bones, about two million per second.
• A hormone called erythropoietin from the kidney can help increase the production.
• Just before and after coming out of the bone marrow, the developing cells are known as reticulocytes; these make up 1% of all the red blood cells in the body.

• Erythrocytes (red blood cells) exist in the body for around 100-120 days and are pushed and pulled through blood vessels like the arteries and veins as well as capillaries.
• The spleen is an organ found in many vertebrates and functions as a blood filter.
• It gets rid of old red blood cells, stores blood in case of an emergency, and recycles iron.
• In adults, the bone marrow produces all red blood cells, some white blood cells and all the platelets.
• The bone marrow and lymphatic tissues such as the spleen, thymus, and lymph nodes produce the rest of the white blood cells.

• Erythrocytes (red blood cells) exist in the body for around 100-120 days and are pushed and pulled through blood vessels like the arteries and veins as well as capillaries.
• The spleen is an organ found in many vertebrates and functions as a blood filter.
• It gets rid of old red blood cells, stores blood in case of an emergency, and recycles iron.
• In adults, the bone marrow produces all red blood cells, some white blood cells and all the platelets.
• The bone marrow and lymphatic tissues such as the spleen, thymus, and lymph nodes produce the rest of the white blood cells.

• Erythrocytes (red blood cells) exist in the body for around 100-120 days and are pushed and pulled through blood vessels like the arteries and veins as well as capillaries.
• The spleen is an organ found in many vertebrates and functions as a blood filter.
• It gets rid of old red blood cells, stores blood in case of an emergency, and recycles iron.
• In adults, the bone marrow produces all red blood cells, some white blood cells and all the platelets.
• The bone marrow and lymphatic tissues such as the spleen, thymus, and lymph nodes produce the rest of the white blood cells.

• The blood vessels that bring oxygen-rich blood to the heart are called coronary arteries.
• The blood vessels that take away deoxygenated blood from the heart are called cardiac veins.

• Thrombin is an enzyme in humans that helps the body form blood clots. It is made from a protein called prothrombin, and it changes fibrinogen (a substance in the blood) into fibrin, which is what helps the body stop bleeding.
• Thrombin also helps start other reactions that help the blood clot.

• Thrombin is an enzyme in humans that helps the body form blood clots. It is made from a protein called prothrombin, and it changes fibrinogen (a substance in the blood) into fibrin, which is what helps the body stop bleeding.
• Thrombin also helps start other reactions that help the blood clot.

• Plasma is the fluid part of blood made up of proteins, salts and 90-92% water, making up around 55% of all the blood. It contains albumin, fibrinogen and globulins (including antibodies

• Platelets are tiny cells in the blood that help with the clotting process by gathering around an injury and sticking to the walls of the blood vessel.
• In a healthy adult, there are typically 150,000-350,000 platelets per microlitre of blood, which is only around 20% of the size of a red blood cell.
• Red blood cells make up the most of our total blood volume, and there are usually 5,000,000 per microlitre.
• White blood cells are the biggest type of cell but the least plentiful, with only 4,000-11,000 per microlitre. The other three statements about blood in a normal person are incorrect.

• Alum is a crystal that contains aluminium ions which can help with clotting. Therefore, it is very effective for stopping the bleeding from a wound.

• Scientists from the University of Sheffield are creating a fake substitute for blood, called ‘plastic blood’.
• It could be very useful in emergency situations, especially in war zones. It is made of plastic, so it’s lightweight, doesn’t need to be refrigerated, can be stored for a long time, and can be transported easily.
• Doctors can keep it as a paste and then dissolve it in water just before giving it to the patients.