organisation Flashcards
What is a cell?
The basic building block of a living organism
What is a tissue?
A group of size with a similar structure and function working together. For example, muscular tissue contracts to bring out about movement.
What is an organ?
A collection of tissues working together to perform a specific function. For example, the stomach contains gland muscular and epithelia tissues.
What is an organ system?
A group of organs working together to form specific functions for example the digestive systems contains organs such as the stomach, the small intestine and the large intestine
What is the main function of the digestive system?
To digest food and absorb the nutrients obtained from digestion
What is the role of the pancreas and the salivary gland in the digestive system?
The pancreas and the salivary gland glands which produced digestive juices containing enzymes
What is the role of the stomach in the digestive system?
Produces hydrochloric acid – which kills any bacteria present and provides the optimum acidic pH for the protease enzyme to function
What is the role of the small intestine in the digestive system?
The small intestine is the site where the soluble food molecules are observed into bloodstream
What is the role of the liver in the digestive system?
produces bile which are emulsifies lipids and allows the lipids enzymes to work more efficiently
What is the role of the large intestine in the digestive system?
Absorb water from undigested food producing faeces
what is the role of enzymes in the digestive system?
Enzymes act as a biological catalyst which speed up the rate of biological reactions without being used up
What types of metabolic reaction do enzymes catalyse?
building larger molecules from smaller molecules, e.g. glucose to starch
Changing one molecule to another e.g. glucose to fructose
Breaking down larger molecules into smaller molecules, e.g. carbohydrates to glucose
How does pH affect enzyme function?
The Optium pH for most enzymes is seven – apart from protease in the stomach
if the pH is too extreme, the shape of the active site may be altered and the enzyme may no longer work
 what is the role of bile in the digestive system?
Bowel is an alkaline substance which neutralises the hydrochloric acid secreted by the stomach. Bile emulsifies lipids to form Droplets – increases the surface area for the lipase enzymes to work on.
What is the heart?
An organ that pumps blood around the body
what is the purpose of the circulatory system?
Carries oxygen and other useful substances to bodily tissues, and remove waste substances
how does the double circulatory system work?
One pathway carries blood from the heart to the lungs – where the gaseous exchange of auction and carbon dioxide takes place
One pathway carries blood from the heart to the tissues
Where does blood pumped by the right ventricle go?
The lungs
where does blood pumped by the left ventricle go?
Bodily tissues
Why is a double circulatory system important?
It makes the circulatory system more efficient for example, oxygenated blood can be pumped around the body at higher pressure by the left ventricle
Why is the wall of the left ventricle thicker?
The left ventricle has to pump blood at high pressure around the whole body
What are the four main blood vessels associated with the heart?
aorta- Carrie auctioned blood from the heart to the body
pulmonary vein - carries auctioned blood from the lungs to the heart
Vena cava-carries deoxygenated blood from the body to the heart
pulmonary artery-curated blood from the heart to the lungs
what is the purpose of coronary arteries?
Connery artery supply the heart muscle with oxygenated blood
how is the heart rate controlled?
Heart rate is controlled by a group of cells in the right atrium which act as a pacemaker. They release waves of electrical activity which caused the heart muscle to contract.
how can an abnormal heart rhythm be treated?
Irregular heart rhythms can be treated using an artificial pacemaker, which sends out electrical signals to correct the hearts riven
How would you calculate the rate of blood flow?
Volume of blood/number of minutes
how would you calculate the breathing rate?
Number of breaths/number of minutes
What are the advantages and disadvantages of a stent?
advantages
Insertion can be carry out with general anaesthetic
Quick recovery time
Lower the risk of heart attack
Disadvantages
Risk of post operative infection
Risk of blood clot at site of stent
what are statins?
 statins are drugs which reduce the level of LDL cholesterol which contributes the development of Connery heart disease
What are the advantages and disadvantages of statins?
advantages
reduce Risk of stroke, coronary heart disease and heart attacks
Increase level of HDL cholesterol
Disadvantages
Have to be taken continuously
May have side-effects
Effect may not be immediate
what is a heart bypass surgery?
A surgery where blocked coronary arteries are replaced with sections of veins taken from other parts of the body
What are the consequence of leaky heart valves?
Blood flows in the wrong direction, causing the heart become less efficient. Patients may become breathless and dies are result.
what type of valves can replace leaky valves?
Mechanical – made of metal or polymers
Biological – taken from animals
what are the advantages and disadvantages of mechanical valves?
Advantages
Last for a very long time
Disadvantages
Need to take medication to prevent blood clotting around the valve
What are the advantages and disadvantages of biological valves?
advantages
Work very well – no medication required
Disadvantages
Only last 12 to 15 years
What is the purpose of an artificial heart?
an artificial heart are intended to support a patient’s heart while they wait for suitable donor heart
What are the advantages and disadvantages of artificial heart?
advantages
Less likely to be rejected by immune system
allows damage heart to rest to help recovery
Disadvantages
Risk of infection due to surgery
Risk of blood clots
Have to take blood thinning drugs
how do carcinogens affect the development of cancer
Ionising radiation is a type of carcinogen which can cause mutations in DNA, potential leading to cancer
how to smoking an alcohol effect on unborm babies
 carbon monoxide from tobacco smoke reduces the oxygen the fetus receives, which can lead to premature birth or still above
Alcohol passes across the person and damages the developing fetus. Once born the baby may have a number of deformities and health problems as part as foetal alcohol syndrome.
what is cancer
Cancer is the development of a tumour as a result of uncontrolled cell division
What is a benign tumour?
a tumour that is contained in one location, usually within a membrane
they are not cancerous and do not invade other parts of the body
Can grow large very quickly – may cause damage to another organ
What is a malignant tumour?
A tumour that can spread around the body via the blood and lymphatic system
Can invade other tissues
Cells divide more rapidly and have longer lifespan
Disrupts healthy tissues and may lead to death
give example of factors which can lead to cancer
Genetics
Smoking
Obesity
Ionising radiation – UV light and x-ray
Viral infections – HPV and cervical cancer
How is the epidermal tissue adapted for its function?
Epidermal tissue covers the entire plant. It has a waxy cuticle which helps reduce water loss from the leaf surface.
how is palisade mesophyll tissue adapted for its function?
Palisade mesophyll tissue contains lots of chloroplast which allow photosynthesis to progress at a rapid rate
How is spongy mesophyll tissue adapted for its function?
Spongy massive fill tissue has lots of air spaces which allow gases to diffuse in and out
how is the xylem adapted for its function?
 made up of dead cells which forms are continuous hollow tube – allows a movement of water and minimal irons from the roots to the leaves
strengthened by lignin– makes the vessel strong and waterproof
Has bordered pets – allow minerals to be transported to specific places
how is the phloem adapted for its function?
made up of elongated living cells
Cells have plates that connect them together – cell sap can move through the plates into other cells
Tube cells have few organelles to allow the efficient transport substances
how is Meristem tissue adapted for its function?
Made up a stem cell which can differentiate into many different cell types along the plant grow
What tissues does the leaf organ contain?
Epiderm
Palaside mesophyll
Spongy mesophyll
Xylem
phloem
God cells
how are root hair cells adapted for their function?
root hair cells allow the uptake of water and mineral irons from the soil
Large surface area – maximises rate of absorption
Contains lots of mitochondria – releases energy for active transport of mineral irons
What is translocation?
Translocation is the movement of dissolved sugars from the leaves to other parts of the plant
 what is transpiration?
Transpiration is the evaporation of water vapour from the surface of the plant
How does transpiration work?
water evaporates from the leaf surface via stomata
what are molecules cohere together – more water is pulled up the xylene in an unbroken column
More water is taken up from the soil – creating a continuous transpiration system
How does temperature affect the rate of transpiration?
increasing the temperature increases the rate of transpiration
Higher rate of evaporation in diffusion of water – therefore rate of transpiration is increased
How does humidity affect the rate of transpiration?
increasing relative humidity, humidity decreases the rate of transpiration
High relative humidity reduce the water vapour concentration gradient. The rate of evaporation will decrease and soil the rate of transpiration.
how does wind speed affect the rate of transpiration?
Increase wind speed/air movement increases the rate of transpiration
Increased air movement lowers water vapour concentration outside of the leaves. This increases the water vapour concentration gradient, thereby increasing the rate of evaporation and transpiration.
How does light intensity affect the rate of transpiration?
increasing the light intensity increases the rate of transpiration
The rate of photosynthesis increases, so Mark open. This last the rate of recreation to increase, increasing the rate of transpiration.
