B4 - Organising animals and plants Flashcards
What is the blood made of
Plasma
Red Blood Cells
White Blood Cells
Platelet’s
What is the function of Plasma
It transports all your:
Blood cells
Waste CO2 produced by cells, to the lungs
Urea formed in the liver, to the kidneys
The small soluble product of digestion, pass into plasma
What is the function of Red Blood Cells
To pick up oxygen from your lungs and carry it to the cells that need it
What is the function of White Blood Cells
They form part of the body’s defence system against harmful microorganisms
They make Lymphocytes which form antibodies
ones that make antitoxins
Phagocytes which engulf and digest the harmful microorganisms
What is the function of Platelets
They help the blood clot at the site of a wound and stop the bacteria entering the body
What are the 3 types of blood vessels
Vein
Artery
Capillary
Which direction does the blood flow in a Artery
Out of the heart
Which direction does the blood flow in a Vein
Into the heart
Which direction does the blood flow in a Capillary
Around the body
Key structures of a Capillary
Narrow lumen
Walls a cell thick
Lets substances to diffuse easily
Key structures of a Vein
Relatively thin walls
Large Lumen
Often have valves to stop backflow
Key structures of a Artery
Thick walls with lots of muscles and elastic fibres in it
Small lumen
What are stents used for
They are used to keep narrowed or blocked arteries open
What are statins used for
They reduce the cholesterol levels in the blood, reducing the risk of coronary heart disease
What is the function of heart valves
They keep the blood flowing in the right direction in the heart
What can replace damaged heart valves
Biological or Mechanical valves
What controls the resting heart rate
A group of cells in the right atrium that form a natural pacemaker
What are artificial pacemakers
They are elctrical devices that correct the irregularties in the heart rythmn
What are artifical hearts
They are machines which pump a patients blood around their body while they are waiting for a transplant
What is the purpose of the diaphragm
It contracts and relaxes to increase and decrease the volume in the lungs while breathing
What is the purpose of the alveoli
It diffuses oxygen into the blood and diffuse CO2 out
What is a lung
It is an organ where gas exchange happens
What is the purpose of the trachea
Carries air to and from the lungs
What is the purpose of the bronchus
Carries air into and out the two sides of the lungs
What is the purpose of the bronchioles
They carry air to the alveoli’s
What is the function of the waxy cuticle layer
To prevent evaporation and protect the leaf
What is the function of the Upper epidermis
To allow as much light as posssible to get through it
Lacks organelles
What is the function of the Palisade Mesophyll layer
To carry out lots of photosythesis
Lots of chloroplast
What is the function of the stoma
To allow air in for gas exchange
What is the function for the spongy mesophyll layer
Gas exchange
Lots of air spaces between the cells
What is the function of the guard cells
Opening and closing the stoma
What does the Phloem do
It transports sugar up and down the stem
The process is called translocation
It is made of living tissue
What does the Xylem do
It transports water up the stem (one direction)
Process called transpiration
Made up of dead cells
Why are Xylem’s made of dead cells
So that nothing gets in the way
What is Transpiration
The movement of water up the stem and then evaportaed out the stomata
Evaporation of some of the water causes more water to be pulled through the xylem
What causes an increase in the rate of transpiration in a plant
Windy weather
Higher temperature
When there is lots of sun
