Bio - circulatory system 1.5-1.6 Flashcards
What substances are carried by your circulatory system?
- Oxygen is carried from your lungs to your cells.
- Carbon dioxide is carried from your cells to your lungs to be breathed out.
- Nutrients are carried from your intestines to your cells.
- Waste is carried from your cells to your kidneys to be removed.
What does your blood also transport and why?
Heat to keep your body temperature at a constant 37 degrees c
What happens to your body temp if it is cold outside
When you go outside, it’s cold and you play with snow your body temp lowers but as soon as your done your heart makes sure to warm you up again so you wont freeze.
What happens to your body temp when its hot outsude?
If you get warm from running around outside then your blood transports heat away form your muscles and towards areas such as your skin and you will sweat and cool down before you overheat.
What happens with a blood sample before and after it gets left out on a desk
before it is all red and warm but, afterwards it separates into 2 large parts with 1 small part in between like an oreo
Where are blood cells formed and how do they exit
95% is formed in the bone marrow, they exit through a dense network of capillaries
What is plasma
It is the yellow-ish liquid component of blood that mainly consist of water.
How much space does plasma take in your blood
Around 55%
What is suspended in the plasma?
Nutrients, waste products like carbon dioxide, hormones and a fraction of the oxygen are suspended in the plasma.
How many layers does your blood have?
3
What are the 2 layers under the plasma contain?
They all contain blood cells and they make up 45% of your blood. They are denser than water and thus are under plasma
How many blood cells are there
There’s 2 main types, red and white blood cells but there are also platelets
What are white blood cells + what is their function
They protect you against illness and disease.
What are red blood cells + what is their function
carry oxygen from the lungs and deliver it throughout our body. Red blood cells also transport waste such as carbon dioxide back to our lungs to be exhaled.
What are platelets
They are not really cells but tiny fragments of cells. They form a thin layer with the white blood cells
How do red blood cells look like and why are they different
Red blood cells are disc shaped, and are different from all other body cells because they lack a cell nucleus.
What do red blood cells carry
They contain a red
substance called haemoglobin, which binds oxygen and that’s how it transports it. Since there’s more red blood cells than white it makes your blood look red
How do red blood cells function without a nucleus?
Losing the nucleus enables the red blood cell to contain more oxygen-carrying hemoglobin, thus enabling more oxygen to be transported in the blood and boosting our metabolism
Do white blood cells have nuclei
Yes, white blood cells do have buclei
How does your body react to having invaders?
Your body reacts to invaders by making more white blood
cells. White blood cells can change their shape and squeeze themselves through capillary
walls. This allows them to enter tissues that have been invaded by harmful germs
How many types of white blood cells are there
There are 5 main types. Phagocytes and Lymphocytes are the ones we will learn about
What do Phagocytes do?
They can change shape and stretch themselves to engulf and
‘swallow up’ bacteria. Then they digest the bacteria into small pieces that are no longer
harmful.
What do Lymphocytes do?
Lymphocytes make substances called antibodies, which are specially produced
to assist the phagocytes in destroying invaders such as bacteria (antigens).
Why do you get ill?
It takes a while before your lymphocytes have made enough antibodies. This is why you get ill.
What happens each time a new invader enters/gets into your body
Each time a new invader gets into your body, a new antibody is produced, specifi c for the
invader
What do they antibodies do?
They surround and stick to the invaders so that the phagocytes can engulf them.
The next time an invader enters the body, the lymphocytes will remember how to make
the specifi c antibodies even faster than before. Which makes you immune.
What is immune?
you will not get ill from a specific type of illness
WHat happens when your organs/tissues get damaged or malfunction?
In such cases a tissue or organ transplant could be a solution.
What should hopefully happen after you get a transplant
If the organ/tissue is taken from
another part of the victim’s body, then the ‘new’ organ/tissue grows and joins together with the
organ/tissue surrounding the burn.
What happens if your body rejects a transplant
if an organ/tissue is taken from another person (a donor
who is not the victim’s identical twin), tissue rejection sets in after a few days and the
‘new’ organ/tissue dies.
If tissue from a random donor is transplanted to a random patient, the patient’s lymphocytes are activated: they will make antibodies against the ‘new’ tissue and this tissue will then be rejected and eventually die.
What are some methods to reduce the chances of rejection
- Tissue typing where doctors try to find a very close ‘match’ between the cells of a
patient and those of a donor. For instance: the closer you are related to the donor,
the smaller the chance of rejection. - Immunosuppressive drugs are given to the patient to suppress the activation of
lymphocytes so that no antibodies are made. However, this also means that the
patient will now be much more sensitive to infections by bacteria and visures.
Doctors will try to find a delicate balance between tissue rejection and preventing
infections by giving more or less of the drugs.
Why are platelets involved in blood clotting (like when skin is cut)?
It is important, to prevent the entry of invaders through the open wound. Also, a clot can prevent blood from flowing out of a punctured blood vessel for too long.
How do platelets make a blood clot to make your body heal (list the process of healing)?
- the platelets are activated by chemicals that are released when a blood vessel is
damaged. They stick to the walls around the wound and to each other. At the same time
they change shape to form a cover that fi lls the opening in the blood vessel wall to stop
blood from leaking out. However, the cover of platelets is still very weak and can easily tear - the platelets send out chemical signals to a substance in your plasma called
fi brinogen. These signals cause fi brinogen to change into sticky thread-like fi bers called
fi brin. Fibrin forms a net across the wound site, so that the platelets stay in place. The net
also traps blood cells and plasma, thus preventing more blood loss. At the same time, it
prevents bacteria and other germs to enter the wound. This network of platelets, plasma
and blood cells is called a clot. - Finally, after the clot is fi rmly in place, it will harden. Now the wound can slowly heal. Below
the hardened clot, which is called a scab, your skin cells are being repaired. As more new
skin cells grow, they push the scab upwards and eventually the scab falls off . Your skin has
healed!
What happens if oyu get a wound under your skin
If this happens, a clot forms in a similar way to prevent your broken blood
vessels from leaking blood. You can clearly see the scab which forms a blue mark below
your skin.
What is haemophilia?
It is an inherited disease that causes their blood to not clot properly, which means they bleed out more than a nprmal person
How is haemophilia caused?
It is caused by a change in DNA that was either passed from
parent to child or happened while the baby was developing in the womb.
Why do people with haemophilia cannot make proper blood clots?
People with haemophilia do not make enough of certain chemicals in their blood
called clotting factors which causes them to not clot properly
What are clotting factors?
Clotting factors help platelets to turn fibrinogen into fibrin
threads.
How many clotting factors are there?
Your blood contains 13 clotting factors, numbered using Roman numerals from I (1) through XIII (13).
What happens when you have too little of clotting factors VII or IX?
Having too little of factors VIII (8) or IX (9) stops the body
from making fibrin threads and this is what causes haemophilia. A person with haemophilia will only lack one factor, either factor VIII or factor IX, but not both.
What are the 2 major kinds of haemophilia?
- Haemophilia A, which accounts for about 80% of cases, is when factor VIII is lacking.
- Haemophilia B is when factor IX is lacking.
How is haemophilia classified?
mild, moderate or severe based on the amount of the clotting factor in the person’s blood.
When is it severe?
If someone produces only 1% or less of the affected factor
When is it moderate?
Someone who produces 2% to 5% has a moderate case,
When is it mild?
someone who produces 6% to 50% of the affected factor level is considered to have a mild case of haemophilia.
What happens when you have a mild case?
a person with milder haemophilia may bleed excessively only once in a while,
whereas severe haemophilia puts someone at risk for having bleeding problems much more
often.
When do people find out they have haemophilia and is it treatable?
Most people with haemophilia discover they have the condition when they are babies or young kids. Today, there are medicines to treat patients with haemophilia.