B1: Flashcards
Why don’t antibiotics target virues?
They have no metabolic reactions to be prevented.
What causes bacteria and fungi to become resistant to antibiotics?
Doctor prescribing incorrect drug.
Not finishing the course.
Explain the Incidence of disease.
Rate of new cases of disease in a population.
Given in 10,000 or 100,000.
Heavily influenced on climate and socio-economic factors
What causes high blood pressure?
Smoking Too much salt Being overweight Stress Too much alcohol and saturated fat
How does Smoking affect blood pressure?
Nicotine causes high blood pressure and carbon monoxide combines with haemoglobin instead of oxygen. Consequently the heart pumps harder.
Explain the key features of saturated fat?
From eggs, red meat and cream.
These food causes the liver to create cholesterol.
Cholesterol is deposited on artery walls and can cause thrombosis.
Define health and fitness
Heath= Mental, physical, social and emotional wellbeing and not merely the absence of disease.
Fitness= the ability to do physical activity
Define the uses of Iron, vitamin C, fibre and water
Iron= to make haemoglobin C= make scurvy Fibre= prevent constipation Water= prevent dehydration & replaces water
Too little protein leads to …..
Kwashikor
Reasons for lack of food in some areas of the world are as followed
Overpopulation,
Little investment in agriculture,
Explain key features regarding BMI
Mass (kg) divided by height (m sqared)
Explain the key features of the different types of proteins.
First class proteins> meat ( contains essential amino acids which the body can not produce)
Second class proteins > plants
What does BMI stand for and what is its purpose?
Body Mass Index
Tells you if you have a healthy body weight.
Explain everything on EAR
Estimated amount required > only applies for protein
EAR= 0.6 x body mass (kg)
Name 5 barriers which is used by your body to prevent pathogens from entering the body.
Skin Stomach acid Mucus in airways Tears Blood cutting when you cut yourself.
Name and explain the 2 types of white blood cells.
1) Phagocytes: they engulf the pathogens
2) Lymphocytes: they produce antibodies and antitoxin
Explain how an antibody kills a bacteria.
They all have different shaped antigens (proteins) on their surface.
Antibodies (proteins) also have a shape which fits into the shape of the antigen.
Immune system make the correct type of antibody to combat it.
Once coated with antibodies. White blood cells ingest it.
Explain immunisation.
1) Dead or inactive pathogen injected in body carrying antigens
2) The antigen trigger a response and cause the white blood cells to produce antibodies
3) A memory cells is created providing long-lasting immunity. The next time pathogens enter; they are killed before the symptoms show.
What is Malaria caused by?
a protozoan called Plasmodium
What does the Plasmodium do?
Feeds on human red blood cells.
What is the name given to the Plasmodium, mosquito and human?
Parasite, vector & host
Give four ways of controlling Malaria.
Draining stagnant water; putting oil on water surface and spraying insecticide.
What waste product do pathogens produce?
Toxins
Give the difference between active and passive immunity.
Active= slow process but long lasting effect Passive= quick process but short lasting effect
What does the antiviral drug do?
Slows down the pathogen’s development.
Explain briefly the stages of a new drug.
Tested on animals, human tissue, computer models before human trials.
What are the reasons for using blind trials to test new drugs?
Neither the doctor or the patient know which is the real drug therefore the “feel-good factor” and a biased opinion is avoided.
Define alleles.
Different version of the same gene.
Name 3 ways genetic variation is caused by.
Mutations = random changes in the genes or chromosomes.
Rearrangement of genes during the formation of gametes.
Fertilisation.
What is a mutation?
Random changes in the genes.
Define zygote.
A fertilised egg.
Name 3 inherited disorders.
Red green colour blindness;
Cystic Fibrosis;
Sickle celled anemia;
What is genotype and phenotype?
Genotype: genetic make up
Phenotype: alleles expressed
What are inherited disorders caused by?
Faulty genes.
What does a positive reaction mean ?
Root or shoot grows towards the stimulus.
What does a positive reaction mean ?
Root or shoot grows towards the stimulus.
Where is auxin made?
In the roots and shoot tip.
Give 4 commercial uses of plant hormones.
Used as selective weed weed killers and to increase crop yield.
Rooting powder to increase root growth of cuttings
To delay or accelerate fruit marketing to meet demand.
To control dormancy in seeds.
Define homeostasis
Keeping a constant internal environment.
Homeostasis involves controlling your body’s inputs and outputs.
Homeostasis involves controlling your body’s inputs and outputs.
Why is it important to keep levels of temp, water and carbon dioxide steady.
To keep cells and enzymes working at an optimum level.
How is blood temperature monitored ?
Hypothalamus gland
What is reaction to temperature extremes controlled by ?
Nervous and hormonal systems
Why are hormone reactions slow?
The hormones travel in the blood.
How do depressants block transmission of nerve impulses across the synapses?
By binding with the receptor molecules in the membrane of the receiving neurone.
What is it called when the liver is damaged by toxic chemicals such as alcohol?
Cirrhosis
What is accommodation?
When the eye focuses light from distant or near objects by altering the shape of the lens.
If convex is to correct long sight, what is concave lens for?
Short sight.
Red green colour blindness is due to
A lack of specialised cells in the retina
How are neurons adapted?
They have long branched endings to pick up impulses and they have an insulator sheath.
What happens to the excess glucose?
Turns it in to glycogen which is stored in then liver.
Difference between type 1 and 2 diabetes?
Type 1 = Caused by pancreas not producing any insulin
Type 2 = body producing too little or the body not responding to it
Describe the functions of the main parts of the eye
• cornea – refracts light
• iris – controls how much light enters pupil
• lens – focuses light on to retina
• retina – contains light receptors, some sensitive
to light of different colours
• optic nerve – carries impulses to the brain.
