L6: the body's defences Flashcards
What is the role of the heart
Pumps blood around the body
What two substances does the blood transportation to cells that are needed for respiration
Oxygen and glucose
What force slows a plane down
Air resistance
If a substance turns UI orange what is it
Acid
What are the smallest blood vessels called
Capillaries
What are elements that have properties of metals and non metals called
Metalloids
What orgam does the cranium protect
Brain
What do we call the pairs that muscles work in
Antagonistic pairs
What type of joint is the shoulder joint
Ball and socket joint
An element has 3 protons and 4 neutrons how many electrons will it have
3
Name two examples of pathogens
Bacteria and viruses
When bacteria invade the body, what do they release and what does it do
Toxins, making us fell unwell
Where do viruses reproduce
In cells
How do viruses make us feel sick
By damaging and killing cels
What are the defences that protect us from diseases called
Immune system
How many lines of defence does our immune system have
3
What is the first line of defence
Barriers to prevent infection
What is the second line of defence
General response to infection
What is the third line of defence
Immunity against specific pathogens
What does the first line of defence do
Tries to stop any pathogen getting in the body
What two types of barriers are in the first line of defence
Physical barriers and chemical barriers
Name four examples of our first line of defence
Skin
Mucous membranes in our breathing system
Chemical in tears
Stomach acid
How does our skin help our bodies against microbes
Prevents them from entering
How does our mucous membranes help our bodies against microbes
It catches and removes them
How does the chemicals in our tears help our bodies against microbes
It kills them
How does stomach acid help our bodies against microbes
Kills them
What does the second line of defence in our bodies do
The white blood cells move in to destroy the pathogens
Are all white blood cells the same
No
Do all white blood cells have the same job
No
What two white blood cells do we need to know about for our test
Phagocytes and lymphocytes
Is the second line of defence specific about which pathogen it targets
No
What do phagocytes do
It targets foreign cells and then surrounds and engulfs them
What is the phagocyte’s process called
Phagocytosis
What does the third line of defence in our bodies do
Special white blood cells destroy the pathogens
What are these special white blood cells called
Lymphocytes
What do the lymphocytes do
- they recognise markers on the pathogens
- they make antibodies specific for the pathogen
What are the markers on pathogens called
Antigens
How do the lymphocytes increase how many lymphocytes there are
Reproduces to make a clone army which can make millions of antibodies very quickly
What happens after the lymphocytes make the antibodies
The phagocytes join in and help get rid of the pathogen
What happens after our immune system has come across a pathogen’s antigen
It will remember it and will be able to fight it off quickly next time
What is immunity
Once our bodies have fought off an infection we become immune
What are memory cells
A special type of lymphocyte
Where do the memory cells remain
In the blood
If you get infected by the same pathogen again, what will the memory cells do
They will reproduce quickly and produce lots of antibodies
How quickly do memory cells remove the pathogen from the body
Before it even has time to make you ill
What do vaccines contain
Dead or weakened pathogens
What do vaccines have which is important
They still have the antigen of the pathogen on
How does our immune system respond to the antigen in a vaccine
As if it were the actual pathogen
What is the effect of the vaccine
It leaves behind memory cells - you’re immune to this particular pathogen
If you were vaccinated and got the pathogen you took a vaccines against, what happens
The memory cells reproduce and make antibodies very quickly
After taking a vaccine, how fast would the response to the pathogen you took a vaccine against be
Destroys the pathogen before you get ill
What is herd immunity
When a large population are immune to a pathogen making it harder for the pathogen to spread
Finish the sentence, the more infectious the pathogen
The larger the immune population needs to be
Name two ways herd immunity can be developed
- Using vaccines
- people catching and recovering from a patogen
How do antibiotics work
They are chemicals that kill bacteria inside the body
Do antibiotics work on viruses
No
Why do we have to use antibiotics with care
More and more bacteria are becoming resistant to them
Name one type of antibiotic
Penicillin
