Microorganisms: information sheet

Microorganisms are very small living things.
You need a microscope to see most of them.
micro = very small
organism = something alive
Sometimes they are called microbes. /
microscope
Bacteria are very small.
  • They are single-celled organisms.
  • They have a cell wall.
  • They do not have a nucleus.
  • Some bacteria are useful.
  • Some bacteria cause disease.
/ /
bacteria
Viruses are extremely small.
  • They are much smaller than bacteria.
  • They are not made of cells.
  • They have a protein coat round their genetic material.
  • Viruses cause disease.
/ /
viruses
You can see some fungiwithout a microscope.
  • Some fungi are single-celled organisms.
  • Some are made of long threads.
  • Some fungi are useful.
  • Some fungi cause disease.
/ /
fungi
Microorganisms: question sheet
List the threetypes of microorganism.
Smallest
Biggest /


Tick  true or false. / True / False / Correct the false sentences.
Viruses are made of cells.
All bacteria cause disease.
Bacteria are single-celled organisms.
Viruses are larger than bacteria.
Some fungi are useful.
Choose a word. / Write the correct word in the space.
  • cells
  • viruses
  • protein
  • single-celled
  • fungi
  • genetic
  • bacteria
  • microorganisms
/ ______are very small living things. ______, ______and fungi are examples of these. Bacteria are ______. Viruses are not made of ______. They have a ______coat round their ______material. Some bacteria and ______are useful.
Pathogens: information sheet
Microorganisms that cause disease are called pathogens (microbes).
Microorganisms cause diseases in different ways:
Influenza (flu) is caused by a virus. / Salmonella (food poisoning) is caused by bacteria. /
Athlete’s foot is caused by a fungus.
Microorganisms need three things to help them reproduce:
warmth / moisture / nutrients (food for growth)
Diseases are caused by:
Viruses attack and invade our body cells and damage them. /

Bacteria produce toxins(poisonous chemicals) which make us ill. /
Fungal infections are spread through direct contact (by sharing towels). /
Microorganisms can enter our body in many different places:

genitals /
nose /
ears

mouth /
eyes

cut /
skin
Pathogens: question sheet
List the threetypes of pathogens.
1. / 2. / 3.
Choose a word. / Write the correct word in the space.
  • damage
  • invade
  • virus
  • toxins
  • microorganisms
  • diseases
/ Pathogens are ______that cause disease. Different pathogens cause different ______. For example, influenza is caused by a ______.
Bacteria produce ______which make us ill. Viruses attack and______our body cells and ______them.
Microorganisms can enter our body in different places. Find the 7 places in the wordsearch. The first one has been done for you.
Find the words here. / Write the words here.
B / C / F / G / T / U / S / eyes
______
______
______
______
______
S / E / Y / E / P / Y / F
N / K / O / N / L / E / M
T / S / K / I / N / S / G
C / R / H / T / U / O / M
S / U / V / A / W / N / H
A / E / T / L / I / L / O
S / G / E / S / R / A / E
P / W / Z / F / N / P / Q
Transmission of microorganisms: information sheet
Some diseases are infectious. That means you can catch them from someone else.
Pathogens are transmitted (passed on) from one person to another in a number of ways.
By breathing droplets /
By eating or drinking contaminatedfood or liquid /
By touch (physical contact) /
By insects or animals /
By blood /
From mother to child /
  • Salmonella is a bacteria. It is passed on by eating contaminated food.
  • Influenza (flu) is a virus. It is passed on by droplets in the air from an infected person, or by physical contact.
  • Athlete’s foot is a fungus. It is passed on by physical contact.
It is very important to wash your hands after you use the toilet and before you eat.
Transmission of microorganisms: question sheet
Write the following sentence out correctly:
you can catch/is a disease that/from someone else./An infectious disease
______
______
The pictures below show the ways in which diseases can betransmitted(passed from one person to another).
Match each picture to its correct description.
/ by insects or animals
/ by blood
/ from mother to child
/ by touch (physical contact)
/ by breathing droplets
/ by eating or drinking contaminatedfood or liquid
By animals
The body’s defences, 1: information sheet
The human body has a number of ‘barriers’ which form the first line of defence against pathogens.
They help to prevent many pathogens from entering the body.
The skinprevents microbes from getting into the blood. If you cut yourself, platelets in the blood stick together to form a clot. They seal the cut with a scab to stop microbes getting in. / /
skin / scab
Tears and sweat contain chemicals which destroy bacteria. / /
tears / sweat
Stomach acid destroys bacteria in food. / stomach
Sticky mucus in your nose and airways helps to trap microorganisms. Tiny hairs called cilia then move the mucus on. / /
mucus / cilia (tiny hairs in the nose)
The body’s defences, 1: question sheet
Complete the names of the 5 ‘barriers’ which the body uses to prevent microbes from entering the body.
  1. s ______a _ _ _ 4. m _ _ _ _
  1. t _ _ _ _ 5.s _ _ _ _
  1. s _ _ _

Match the “barrier” to the part(s) of the body where it is found.
tear / / all over the body
acid / nose and airways
skin / stomach
mucus / eyes
Write out 4 correct sentences about the body’s ‘barriers’.
Use a word or phrase from each column.
Mucus
Skin
Stomach acid
A scab / seals
destroys
traps
prevents / bacteria in food.
a cut.
microbes from entering the body.
microorganisms.
1.
2.
3.
4.
The body’s defences, 2: information sheet
If pathogens get past the first line of defence and enter your body, there is a second line of defence: the immunesystem. The white blood cells are a vital part of the immune system.They fight infections in our bodies.Phagocytes are one type of white blood cell. They destroy pathogens by engulfing them. /
Yellow phagocyte engulfs the pathogen
B-cells and T-cells are another type of white blood cell (lymphocytes).Each pathogen leaves an antigen on the surface of cells it infects.T-cells recognise the pathogens by receptors on their surface. B-cells produce antibodies. They are Y-shaped.These antibodies lock onto the antigens.The antigens can then be destroyed in different ways.Each antibody is specific to one antigen. This means that each antibody can only lock onto just one type of antigen.

Different B-cells with antigen receptors
After the immune system has produced antibodies for one illness, some of the antibodies remain as ‘memory cells’. This means that your body will react more quickly to fight off that illness if you meet it again.
The body’s defences, 2: question sheet
The sentences below all contain a mistake. Write each sentence out with the CORRECT facts.
  1. Phagocytes are a type of pathogen.
______
  1. T-cells produce antibodies.
______
  1. Antibodies are many different shapes.
______
  1. Antibodies can lock onto any antigen.
______
The sentences below describe what happens when pathogens attack a person’s body and the immune system fights them. They are in the wrong order.
The antibodies help to destroy the pathogens.
T-cells recognise the pathogens.
Pathogens enter the body.
The person begins to feel well again.
B-cells make antibodies.
The pathogens reproduce and make toxins.
Write them out in the CORRECT order here.
1.
2.
3.
4.
5.
6.
Antibiotics and vaccines: information sheet
Antibiotics are medicines that are prescribed by doctors. They do not affect viruses, so are not prescribed for colds or flu.


Antibiotics kill bacteria Antibiotics stop bacteria from growing.
Some types of bacteria are no longer affected by certain antibiotics.
This is called antibiotic resistance.This can be a problem, as some people might not be able to fight infections themselves, without the help of effective antibiotics.

There are lots of Antibiotics kill the illness The antibiotic
germs. A few are as well as the good bacteria resistant bacteria
antibiotic resistant. protecting the body. grow.
Vaccines are another way of helping your immune system to fight some diseases.The process is called vaccination or immunisation. /
Dead or inactivemicrobes are injected into your body.You do not become ill, because the microbes are not active, but your immune system produces antibodies to fight the microbes. This means that if this disease ever infects your body, you already have the antibodies there to fight it off. /
Antibiotics and vaccines: question sheet
Read the paragraph below. Cross out the wrong word in each pair of boldand italic words. The first one has been done for you.
Antibiotics and fungi / vaccines can help your immune / digestive system to fight diseases. Antibiotics are medicines / pathogens which can kill viruses / bacteria but not viruses / bacteria. Unfortunately, some bacteria have become natural / resistant to certain antibiotics, so they can no longer be killed by them. Vaccines contain dead or inactive / live microbes which make your immune system react to them and produce antigens / antibodies. If the real, active disease tries to infect you after that, the pathogens / antibodies will fight it off.
/ Across
2. Bacteria which are not affected by a particular antibiotic.
6. These can be killed by antibiotics.
7. A microorganism which is not affected by antibiotics.
Down
1. A form of a pathogen which will not give you the disease it causes.
3. Drugs which kill or weaken bacteria.
4. White blood cells make these to destroy microorganisms.
5. Contain inactive or dead microbes.