Unit 1A - Human Biology Flashcards
What five things make up a balanced diet?
Carbohydrates, fats, protein, fibre and vitamins/mineral ions
Where do humans get their energy from?
Food
Why do we need to eat carbohydrates?
To release energy
Why do we need to eat fats?
To keep warm and release energy
Why do we need eat protein?
Growth, cell repair and cell replacement
Why do we need to eat fibre?
To keep everything moved smoothly through your digestive system
Why do we need to eat vitamins and mineral ions?
To keep your skin, bones, blood and everything else healthly, to prevent deficiency diseases
What is your metabolic rate?
The rate at which the chemical reactions in your body take place
Which three people are likely to have a faster metabolic rate and why?
- ) People with a higher proportion of muscle to fat in their bodies, because muscles need more energy than fatty tissue
- ) Bigger people because you have more cells which require more energy
- ) Men over women because they are larger and have more muscle
How can regular exercise boost your metabolic rate?
It builds muscle and muscles require more energy than fatty tissue and therefore increasing your metabolic rate
How does activity level affect your diet?
If you do little exercise you need less energy, so less fat and carbohydrate in your diet
You health is affected by what three things?
Unbalanced diet, not getting enough exercise and inherit tied factors
What does it mean to be malnourished?
It is people whose diet is badly out of balance
Are malnourished people thin?
No they can be fat or thin
What’s the difference between malnourishment and starvation?
Starvation is not getting enough food of any sort and malnourished is just a really unbalanced diet
Eating too much of which food group can lead to obesity?
Excess carbohydrate or fat
What is obesity defined as?
20% or more over the maximum recommended body mass
What four things can cause obesity?
Hormonal problems, bad diet, over eating and a lack of exercise
What five health problems can being obese cause?
Arthritis, type 2 diabetes, high blood pressure, heart disease and it is a risk factor of some kinds of cancer
Eating too much of what can cause an increase in your blood cholesterol level?
Saturated fats
Eating too much salt can cause what?
High blood pressure and heart problems
Malnutrition causes by a lack of food can cause?
Slow growth in children, fatigue, poor resistance to infection and irregular periods in women
What are deficiency diseases caused by?
A lack of vitamins or minerals
What is scurvy and how is it caused?
Lack of vitamin c, a deficiency disease that causes problems with skin, joints and gums
How can people be fit but not healthy?
You can be physically fit and slim but be malnourished because your diet isn’t balanced
Why does exercising mean you are less likely to suffer from health problems such as obesity?
Exercise increases the amount of energy used by the body and decreases the amount of stored fat, it also builds muscle boosting your metabolic rate
What inherited factor can affect your metabolic rate?
An under active thyroid gland is inherited and can lire the metabolic rate
What four things would tell you claims about slimming products are true?
- ) if the report is a scientific study
- ) if it was written by a qualified person not contacted to the people selling it
- ) if the sample of people asked or tested on is large enough to give reliable results
- ) if there has been other studies which found similar results
How do you lose weight?
Take in less energy than you use, eat less carbohydrate and fats (so you take in less energy) and do more exercise (so that you use more energy)
What is a pathogen?
It is microorganisms that enter the body and cause disease
Are bacteria or viruses living cells?
Bacteria are very small living cells
Viruses are not cells
What’s the difference in size of a virus compared to bacteria?
Virus is 1/100th the size of a bacterium, and so a lot smaller
How does a virus reproduce?
They replicate themselves by entering your cells and using the cell to make copies of themselves until the cell bursts releasing the new virus
How does bacteria make you feel ill?
Damaging your cell and by producing toxins
How does a virus make you feel ill?
Through cell damage
What is in the respiratory tract to help the bodies defence system?
Hairs and mucus to stop things getting into the body
How does your body try to prevent microorganism getting in through cut?
Small fragments of cells called platelets help the blood to clot quickly to seal the wound not allowing microorganisms to enter
What is the cell called that helps to clot blood?
Platelets
What are the three ways that white blood cells can kill pathogens?
Consuming them, producing antibodies, or producing antitoxins
How to white blood cells consume pathogens?
They simply engulf and foreign cells and digest them
How do antitoxins help the defence system?
They counteract toxins produced by the invading bacteria
Why can’t antitoxins work against virus’s?
Because viruses don’t produce toxins like bacteria does
How to antibodies help kill invading cells?
Every invading cell has unique antigens on its surface, when a white blood cell comes across a foreign antigen they will start go produce proteins called antibodies to lock onto and kill the invading cells
Why can’t antibodies kill any invading cell?
They are specifically to lock onto one type of antigen and so they would not able to kill any invading cell
What happens is a person is infected with the same pathogen again?
The white blood cells will recognise the antigen and rapidly produce antibodies to kill it
What does a vaccination prevent?
Any future injections
What do vaccinations involve?
Injecting small amounts of dead or inactive mircrooanisms, these carry a hyphens which cause your body to produce antibodies to attack them, even though the microorganism is harmless. This means is the live microorganism ever was to appear again then your white blood cells can rapidly mass produce antibodies to kill off the pathogen.
What does the MMR vaccine contain?
Weakened versions of the viruses that cause measles, mumps and rubella
Why do you need booster injections?
As some vaccinations wear off and so a booster may be given to increase the levels of antibodies again
What are two pros of vaccinations?
They have helped to control lots of infectious diseases that were once common in the UK and they prevent big outbreaks of the disease
What diseases were once common in the UK before vaccinations?
Polio, measles, whooping cough, rubella, mumps, tetanus and small pox
How do vaccinations help to prevent epidemics?
If a large percentage of the population is vaccinated, that means even people who aren’t vaccinated are less likely to catch the disease because there are fewer people able to pass it on
What are two cons of vaccinations?
They don’t always work and give you immunity, you can sometimes have a bad reaction to a vaccine
What type of drug relieves symptoms?
Pain killers just relieve pain they don’t tackle the cause of the disease
What type of drugs reduced symptoms?
Cold remedies reduced symptoms but don’t cure the cold
How are antibiotics different to pain killers?
Pain killers just relieve pain where as antibiotics kill or prevent yeh growth of the bacteria causing the problem
Why is it important to use the right antibiotics when treating an illness?
Different antibiotics kill different types of bacteria
Why can’t you use antibiotics to cure the flu or a cold?
They are both viruses, viruses reproduce using your own body cells which means you can’t destroy them us using antibiotics whiteout killing the body’s cells
How do you get bacteria that is resistant to antibiotics?
Bacteria can mutate, sometimes the mutations cause them to be resistant to antibiotics, so when you get an infection some of the after is may be resistant to antibiotics, this means when you treat the infection only the non resistant strains of bacteria will be killed, so the individual resistant bacteria will survive and reproduce creating more bacteria that is resistant to antibiotics
What is an example of an antibiotic resistant bacteria?
MRSA
How are doctors tying to slow down the rate of development of resistant strains of bacteria?
By not over prescribing antibiotics
What can microorganisms be grown in?
In a culture medium
What is in a culture medium?
An agar jelly plate containing the carbohydrates, minerals, proteins and vitamins bacteria needs to grow
How do you grow bacteria in a petri dish?
Inoculating loops are used to transfer microorganisms to the culture medium and the microorganisms then multiply. Paper disks are soaked in different types of antibiotics and placed on top of the culture medium. All non resistant strains of bacteria will die around the disks. The more effective an antibiotic is the bigger the circle will be
How and why do the culture medium and inoculating loops need to be sterilised before use?
They are passed through a flame so that unwanted microorganism don’t grow and affect the results
Why does the petri dish need to have a lid?
To stop any microorganism in the air contaminating the culture
Why and at what temperatures are microorganism grown in schools?
At about 25c because harmful pathogens aren’t likely to grow at this temperature
Who cut deaths by using antiseptics?
Ignaz Semmelweis
While Semmelweis was working in Vienna General Hospital in the 1840s what did he notice?
Women were dying in huge numbers after childbirth from a disease called puerperal fever
How did Semmelweis believe doctors where spreading the disease and how did he solve it?
They were spreading the disease through their unwashed hands and the bacteria and their hands, he told doctors entering to wash their hands in an antiseptic solution
How much did Semmelweis cut the death rate of the women on his ward?
From 12% to 2%
Why was Semmelweis’s idea of washing hands in an antiseptic solution stop when he left the hospital?
They didn’t know about bacteria being a part in causing disease until 20 years later so he couldn’t prove his idea and so his methods were dropped when he left
Why is it it more easy to pass on an antibiotic resistant bug?
People who have become infected can’t get rid of it easily and so there is more chance of passing the infection on
What is the biggest worry about bacteria at the moment?
It can mutate to produce new strains, which could be anti biotic resistance and so current treatments wouldn’t work, or the new strain could be completely new and so no one old be immune to it, this means the new strains can spread rapidly in the population and even cause an epidemic
What is the biggest worry about viruses at the moment?
Viruses mutate often and so it is hard to develop vaccines against the, because the change in their DNA can lead to them having different antigens and so old vaccinations wouldn’t work. The virus could spread easily and be ever more deadly and infectious after mutating
What does the nervous system allow you to do?
React to what goes on around you
What do sense organs detect?
Stimuli
What is a stimulus?
Change in your environment which you may need to react to
How many sense organs do you have?
Five
What are the five sense organs?
Eyes, ears, nose, tongue and skin
What do sense organ contain?
Receptors
What is a receptor?
A receptor is a group of cells which are sensitive to a stimulus, they change stimulus energy into electrical impulses
Name eight stimulus.
Iight, sound, touch, pressure, pain, chemical or a change in position or temperature
What receptors are in eyes?
Light receptors
What receptors are in ears?
Sound and balance receptors
What receptor is in the nose?
Smell receptors
What receptor is in the tongue?
Taste receptor
What are the receptors in the skin sensitive to?
Touch, pressure, pain and temperature change
What stimuli are smell and taste receptors sensitive to?
Chemical stimuli
What is a sensory neurone?
Nerve cells that carry signals as electrical impulses from the receptor in the sense organs to the central nervous system
What is a relay neurone?
The nerve cells that carry signals from sensory neurones to motor neurones
What is a motor neurone?
The nerve cells that carry signals from the central nervous system to the effector muscles or glands
What is an effector in the nervous system?
Muscles or glands are known as effectors and they respond in different ways, muscles contract in response to a nervous impulse whereas glands secrete hormones
What does CNS stand for?
The central nervous system