combined science - bio Flashcards
What is a stem cell ?
A stem cell is an undifferentiated cell. This means that it has not yet specialised,
Mitochondria
Mitochondria are where most of the reactions for aerobic respiration take place
explain how a nerve cell is adapted to carry out it’s specialized function.
- a nerve cell is long to cover more distance.
- has branched connections at its ends to connect to other nerve cells.
what the role of a nucleus
The nucleus contains the genetic material that controls the activities of the cell
what’s a tissue
A collection of similar cells that work together.
where is bile produced and stored
- A Bile is produced in the liver
- stored in the gall bladder.
Benign meaning
Benign means that something is not harmful or not cancerous.
which type of tumour is cancerous
Malignant because it means that something is cancerous or harmful.
what colour is iodine solution in the presence of starch ?
Iodine solution turns blue-black in the presence of starch.
what’s the function of palisade mesophyll tissue ?
The function of palisade mesophyll tissue is where photosynthesis happens.
what is the role of protease enzymes ?
Protease enzymes catalyse the breakdown of proteins into amino acids
Describe the function of phloem tissue.
Phloem tissue transports (dissolved) sugars from the leaves to the rest of the plant
Give three components of blood that are carried in the blood plasma.
red blood cells / white blood cells / platelets
Protease enzymes catalyse the breakdown of proteins into amino acids describe what happens to an enzyme if the temperature is too high
Some of the bonds holding the enzyme together break /1 mark]. This changes the shape of the enzyme’s active site [1 mark]. As the enzyme’s active site is essential to its function, it won’t work anymore
when breathing in, which structure(s) does air enter first ?
trachea
why is the shape of an enzyme important for its function ?
So that it fits the substance involved in the reaction it is catalysing
What artificial device can be used to keep arteries open and blood flowing?
A stent can be used to keep arteries open and blood flowing.
what is the function of a white blood cell ?
White blood cells fight infections by attacking and destroying harmful bacteria, viruses
what is the name of the cell that controls the opening and closing of stomata ?
guard cell.
what would you use to test for the presence of protein
Biuret reagent
give one advantage of using an artificial heart rather than transplanting a natural one.
An artificial heart can reduce the risk of organ rejection and the need for immunosuppressants.
give one risk factor that can increase a persons chance of developing liver disease.
Heavy alcohol consumption can increase the risk of developing liver disease.
describe what a benign tumour is
A benign tumor is a type of abnormal growth that does not spread to other parts of the body.
explain how increasing air movement around a plant’s leaves would affect the rate of transpiration
Increasing air movement around a plant’s leaves would increase the rate of transpiration.
what is the first stage of testing a new medicinal drug ?
The first stage of testing a new medicinal drug is preclinical testing in a laboratory.
what’s a microorganism that causes disease called ?
A microorganism that causes disease is called a pathogen.
what drug was developed by Alexander Fleming
Alexander Fleming developed the drug penicillin.
can antibiotics kill viruses?
No, antibiotics cannot kill viruses.
how does the body help defend the body against pathogens ?
The body helps defend itself against pathogens by using immune cells and antibodies.
which type of pathogens causes rose black spot on leaves ?
Gonorrhoea is a disease caused by
The pathogen that causes rose black spot on leaves is a fungus.
which type of drug are used to control HIV and how?
- antiretroviral medicines
- stops virus replicating in body
- allows the immune system to repair itself and prevent further damage.
what is HIV
a virus that can spread through sexual contact
explain why the tobacco mosaic virus (TMV) affects the growth of plants
TMV affects plant growth by causing cells to lose their shape and stunting plant growth.
Explain how mosquito nets help to prevent the spread of malaria
Mosquito nets prevent the spread of malaria by keeping mosquitoes away from people while they sleep.
explain how vaccination can protect against against a disease
Vaccines can protect against diseases by helping the body develop immunity to the disease.
what is penicillin
Penicillin is an antibiotic that is used to treat bacterial infections.
which disease in humans can be partially controlled by vaccinating poultry against the pathogen.
salmonella food poisoning
what do white blood cells produce to help defend against pathogens ?
White blood cells produce antibodies to help defend against pathogens.
how do viruses make you feel ill
the viruses live inside your cell and replicate themselves
the cell then bursts releasing all the viruses
this cell damage is what make you sock
how does the nose help to defend the body against disease ?
The nose hair (mucus) helps defend the body by trapping pathogens in particles and filtering the air.
what is the double-bind trial and why is it used in clinical trials ?
