Cells & Immunity Flashcards
What is used to make a cell more viable?
Stains like iodine are use to make the structures of a cell more visible.
What are cells
Every living organism is made up of one or more cells nothing smaller than a cell can lead to independent life and show all characteristics of a living thing.
What do onion cells look like?
What do cheek cells look like?
A brick wall.
Little blobs
Label the microscope
Coarse focus
Eyepiece
Fine focus
Arm
Objective lens
Specimen
Stage
Light/Mirror
Base
Cells are the basic units of living things.
What do cells cells normally contain?
Cytoplasm
Nucleus
Cell membrane
What do plant cells contain?
Cell wall
Cell membrane
Vacuole
Chloroplast
Nucleus
Cytoplasm
What dose the nucleus do?
It contains chromosomes that carry instructions to control all the cell activities.
What does the cytoplasm do?
The fluid filling of the cell. The process needed to keep the cell alive take place in the cytoplasm.
What does the Cell Membrane do?
Controls movement of substances in and out of cells.
What does the cell wall do?
Made of cellulose. It gives plant cells their shape, protection and prevents them from bursting.
What do Chloroplasts do ?
Site of photosynthesis. Found only in plant cells.
What does the Vacuole do?
The vacuole contains a solution of sugars and salts. It helps maintain the shape of a plant cell.
Nerve Cell
They have a long insulated fibre to carry electrical messages through the body.
Root hair Cell
Have a large surface area to allow them to absorb water and minerals easily from the soil.
Sperm Cell
Have a long tail to allow them to swim towards an egg so that fertilisation can take place.
Red blood Cells
Has a large surface area and does not contain a nucleus so there is more room for oxygen.
Carry oxygen around the body.
They are small and flexible.
Pollen Cell
They are used in plant reproduction and some have spikes to stick to animals and others have small air sacks to catch the wind.
White blood cells
Some can change shape to engulf and digest microbes. Others defend the body by producing antibodies.
Palisade Cells
They are found near the surface of leaves. They have extra chloroplasts these are need for the plant to produce its own food by the process of photosynthesis.
Muscular Cells
They are found all through your body. They can contract to move your bones and they make your heart beat. Or move food through your digestive system.
What do Micro-organisms require to grow and reproduce?
Food
Water
A suitable temperature not too hot or too cold
Suitable ph you can add acidic vinegar to change the hp
Can’t be too dry
You can add chemicals like: salt sugar
How can we incubate microbes?
By using a Petri dish and nutrient agar
Name the three types of microorganisms
Bacteria
Fungi
Viruses
What are bacteria?
They are single called organisms that can divide very fast to produce new cells.
Bacteria are found almost everywhere, some can be useful but some are harmful to humans and cause disease.
Fungi
They are varied
Some like yeast are microscopic.
Others like bread mould are made up of tiny threads do three bodies are quite large.
Some fungi are very large like mushrooms.
Some fungi are helpful, they produces antibiotics, yeast is used in brewing and baking.
Some are harmful to humans and cause diseases or can be poisonous to eat.
Viruses
They are considered the smallest type to microbe.
Viruses are really the worst microbe. They cause diseases in animals and plants.
Antibiotics
They help treat and cure bacterial infections. Penicillin is made by a fungus and was discovered by Alexander Fleming in 1928. Since then other antibiotics have been discovered there are many available now.
You can test them by using a Petri dish that is filled with bacteria. The clear area around the disc indicate no bacterial growth.
First line of defence
Lysozyme are enzymes in tears that have antiseptic properties.
The skin, it also has sweat that contains lysozymes to kill bacteria.
Blood clotting, if the skin is cut the blood clots to form a scab.
Cells in the respiratory tract produce mucus
Hydronic avid in the stomach kills bacteria
Urine flushes microbes away from the bladder.
Immunity
The ability of the body to resist infection by a pathogen or to overcome it if it succeeds in invading and infecting the body.
Pathogens can sometimes get past the first line of defence barriers.
Second line of defence
White blood cells act as the second line of defence. They move towards the bacteria, engulf the bacteria and digest the bacteria. Other types rely on the body to recognise if a cell belongs there or not.
Antigens
They are a complex molecule on a cell that is recognised my the body and the White blood cells.
The white blood cells recognise your own cells by their “self” antigens.
If they find an antigen that they do not recognise then they treat it as a pathogen and produce a an immune response.
Antigens are recognised by their shape.
Antibody
They attach to the pathogens antigen and clumping them together so they can be destroyed.
When a white blood cell meets a pathogen a make antibodies that will fit perfectly for its antigen.
Developing Immunity
When you are infected by a pathogen, it takes time for the body to start fight the infection.
Your body produces antibodies during this time you will feel ill but will recover when there are enough antibodies.
If you are infected by the same pathogen again Cells will act quickly and the pathogen is destroyed before it can make you ill.
Vaccinations
You can develop immunity artificially through a vaccine.
Vaccines contain a weaker or dead form of the microorganism. That cannot cause the disease but allows the body to learn how to produce the right antibodies.
Explain the primary and secondary response that your body’s has when you are vaccinated…
Primary antibody response m: the antibody concentration rises gradually and peaked about 2 weeks after vaccination.
Secondary antibody response: the antibody concentration rises quickly and the response is more intense. The antibody concentration remains higher for longer.
