Organisation Flashcards
What is the organisational hierarchy
Cells
Tissues
Organs
Organ systems
What is a cell
A basic building block that makes up all living organisms
What is a tissue
A group of cells that work together to carry out a particular function
Examples of tissues and their functions
Muscular tissue - contracts to move whatever it’s attached to
Glandular tissue - makes and secretes chemicals such as enzymes or hormones
What is an organ
A group different tissues that work together to form a specific function
eg glandular tissue which makes digestive juices
What is an organ system
A group of organs that work together to perform a specific function
eg liver producing bile
What are enzymes
enzymes are catalysts produced by living things
What happens to the enzyme if the temperature gets too hot
The bonds holding the enzyme together can break and change the shape of the active site - this is called denaturing
What do enzymes do to big molecules
Break down big molecules which make the it easier for the smaller molecules to pass through the walls of the digestive system and therefore absorbed
Enzyme for carbohydrates
Carbohydrase
eg Amylase
Made in salivary glands, pancreas, small intestine
Enzyme for proteins
Protease
eg Pepsin
made in stomach, pancreas, small intestine
Enzyme for lipids
Lipase
made in pancreas, small intestine
What does an enzyme need to work optimally
Temperature and pH
What do carbs break down into
simple sugars e.g glucose
What do proteins break down into
amino acids
What do lipids break down into
glycerol and fatty acids
What does bile do
emulsifies fats into tiny droplets
neutralises stomach pH
Where is bile made and stored
Made in liver
Stored in gall bladder
What is bile’s pH
7-8
Describe gas exchange in the alveoli
Oxygen diffuses out of the alveolus and Carbon Dioxide diffuses out of the blood into the alveolus to be breathed out
What is a double circulatory system
Where the blood passes through the heart twice before being distributed
How does the heart pump blood around the heart
Into RA via Vena Cava
Into RV past Atrioventricular valves
Past Semi-lunar valves into pulmonary artery into lungs
OXIDISED
Into LA via pulmonary vein
Into LV past vale
Into aorta past valve
DISTRIBUTED
How is your resting heart rate controlled
It’s controlled by a group of cells in the RA wall that produce small electrical impulses causing the muscle to contract
What does an artificial pacemaker do
Control heartrate by sending electrical current to keep the heart beating
What do arteries do
Take blood away from the heart
What do veins do
Take blood to the heart
What do capillaries do
Are involved with the exchange of materials at tissues
How are arteries adapted
small lumen to maintain high pressure
Elastic fibres to stretch
How are capillaries adapted
Permeable walls for diffusion
1 cell thick walls
How are veins adapted
bigger lumen to help blood flow
valves to keep blood flowing in the right direction
How are red blood cells adapted
Biconcave - Large SA
No nulceus - more room to carry O2
haemaglobin that helps to carry O2
How are white blood cells adapted
Can produce antitoxins
How are platelets useful
Chemical reactions involving them cause clotting of a wound
What does blood plasma carry
Red and white blood cells and platelets
Nutrients eg glucose
CO2
Urea
Hormones
Proteins
Antibodies and antitoxins
What are stents
They are tubes that are inserted into arteries keeping them open
Advantages and disadvantages of stents
+ lower risk of HA
+ recovery time is quick and relatively riskless surgery
- can have complications from surgery such as a blood clot
What do statins do
Reduce the amount of LDL cholesterol in blood stream
Advantages and disadvantages of statins
+ reduce the risk of strokes and HAs
+ can increase the amount of HDL cholesterol
+ may help prevent other diseases
- long term drug that must be taken regularly
- sometimes negative side effects such as headaches
- effect isn’t instant
What is health
The state of complete physical and mental wellbeing
What do artificial hearts do
They pump blood for someone who’s heart has failed
+ less likely to be rejected
- the patient has to take blood-thinning drugs as there is a risk of clotting
What do biological and mechanical valves do
Fixes a damaged or leaky valve
Can be biological
+ less risk of clots forming
- don’t last as long
Mechanical
+ last longer
- more risk of clots
What are non-communicable diseases
Diseases that cannot spread between humans or between animals and humans
What are communicable diseases
Diseases that can spread between humans or between animals and humans
What is one way depression can be triggered
When someone is suffering from severe physical health problems
What can immune system reactions caused by infection trigger
Allergic reactions or worsen the symptoms of asthma
What are risk factors
Things that are linked to an increase in likelihood that a person will develop a disease
What is smoking linked to
Cardiovascular disease, lung disease, and lung cancer, damaged foetuses
What is obesity linked to
Type 2 diabetes
What is alcohol linked to
Liver disease and brain function
How is non-communicable diseases be costly
Cost on NHS to research and treat millions of patients
May also put someone out of work and affect economy
What is cancer caused by
Uncontrolled cell growth and division
What is a benign tumour
Where the tumour isn’t cancerous and stays in the same place
What is a malignant tumour
Where the tumour is cancerous and can spread through the bloodstream
Risk factors for cancer
Smoking
Obesity
UV exposure
Viral infection
Genetic factors - BRCA mutations have been linked to breast cancer
Epidermal tissue
Covers the plant and is covered in a waxy cuticle to reduce water loss by evaporation
The upper epidermis is also transparent to allow light in
Palisade mesophyll tissue
Where photosynthesis occurs - lots of chloroplasts
Spongy mesophyll
Air spaces to allow gases in diffuse in and out
Xylem and phloem
Form a network of vascular bundles
Meristem
Undifferentiated cells to help the plant grow
What does phloem do
Transport food substances made in the leaves to the rest of the plant for use
How is phloem adapted
Elongated and have small pores in end walls to allow cell sap to flow through
Transport goes in both directions (called translocation)
Factors that affect the rate of transpiration
Light intensity
Temperature
Air flow
Humidity
How are guard cells adapted to open/close stomata
Kidney shape
Thin outer walls and thick inner walls
Sensitive to light and close at night
On the underside