3a Flashcards
What causes type 1 diabetes? How is type 1 diabetes controlled?
If you have type 1 diabetes, your body can’t make insulin so your blood glucose becomes too high. This is treated with insulin injections in order to maintain the levels of it.
Describe what happens when blood glucose is too high.
When blood glucose is too high, it can cause;
Increased thirst and/or hunger, Frequent urination, Sugar in your urine, Headache, Blurred vision, Fatigue
What are the advantages and disadvantages of a kidney transplant over dialysis?
Advantages;
Available to all kidney patients (no shortage) and no need for immune-suppressant drugs
Disadvantages;
Patient must limit their salt and protein intake between dialysis sessions
Expensive for the NHS and regular dialysis sessions – impacts on the patient’s lifestyle
How does kidney dialysis work?
Blood flows through the dialysis machine where ALL the urea and SOME of the water and salts diffuse through a partially permeable membrane into the dialysis fluid. The clean blood is then transferred back to the body.
Name three things that are reabsorbed by the kidneys
- some water
- some ions
- all glucose
Explain why your urine is likely to be more concentrated on a hot day
When it is hot, we sweat more and so we lose more water from our body. This makes urine more concentrated as more fluid is lost in other ways.
Give three ways in which water is lost from the body
- urine
- sweat
- breathing
What three main jobs do the kidneys do in the body?
- to remove waste from the body
- control blood pressure
- balance the body’s fluids
Write down three main things the body can do to reduce heat loss if it gets too cold
- contract the muscles, which results in shivering
- blood vessels constrict
- hairs on the body stand up
Write down four things that the body needs to keep fairly constant
- body temperature
- glucose levels
- amount of water in the body
- salt levels
Define homeostasis
It is the maintaining of a constant internal environment
What does a stent do?
A stent expands and widens and artery in order to prevent a blockage from becoming fatal. It ensures that blood is still able to flow through.
State one part of the heart that can be replaced with artificial parts, and give one potential complication.
A pacemaker can be replaced if it is faulty but it runs the risk of being rejected by the immune system.
Explain how artificial blood products can help keep people alive.
People who cannot accept blood transfusions for religious reasons can accept artificial blood. Artificial blood delivers oxygen to the body faster than real blood which can limit bodily injury, particularly during heart attack.
What are the cell fragments called that help blood to clot? Why is it important that blood can clot?
Platelets - blood has to clot to create scabs. These scabs prevent pathogens from entering the body, meaning that the person is prevented from getting ill.
What’s the substance in red blood cells called? What is it called when it combines with oxygen?
Hemoglobin
When reacted with oxygen it becomes oxyhemoglobin.
Explain how capillaries are adapted to their function
Capillaries have very thin walls which let gases diffuse in or out quickly.
There is a huge length of capillaries which gives a large surface area.
Why do arteries need very muscular, elastic walls?
They experience thew highest blood pressure and so thick, elastic walls ensure they can withstand the pressure.
Give the function of the
1 - atria
2 - ventricles
3 - valves
1 - push blood into the ventricles
2 - force blood into the pulmonary artery and aorta
3 - make sure blood travels in the right direction
Explain why our circulatory system is called a double circulation system
One system pumps deoxygenated blood to the lungs.
The other pumps oxygenated blood to the rest of the body.
What is the transpiration stream?
Transpiration is thew loss of water from a plant. It is caused by the evaporation and diffusion of water from inside the leaves.
Describe the role of the
1 - xylem
2 - phloem
1 - take water and minerals from the roots to the stem and leaves
2 - transports food substances to the growing regions
Give the two main differences between active transport and diffusion
Active transport goes from a lower concentration to a higher concentration.
Active transport can only take place in water.
Why is a root hair cell that shape?
The hairs that grow out give the cells a bigger surface area so they can absorb the maximum amount of water and minerals.
