Biology Unit 3 Flashcards
What effect does a greater difference in concentration do to diffusion?
When there is a larger concentration difference (Concentration Gradient) there is a faster rate of diffusion.
What is diffusion?
The movement of a particles of a liquid or gas from an area of high concentration to low concentration.
What is the difference in concentration called in diffusion?
Concentration Gradient.
Give an example of diffusion.
Diffusion of CO2 and O2 out and in cells.
What is the difference between Osmosis and Diffusion?
Diffusion is any gas or liquid while Osmosis is specifically Water
What does water need to go through in osmosis?
A partially permeable membrane
Where does water go to in Osmosis?
From a dilute to a higher concentrated liquid
What happens if cells are put in a solution with a higher solute concentration?
The water moves out through osmosis
It then shrivels up and dies
Why would an animal cell burst?
Because it is in a dilute solution, causing osmosis into the cell and it eventually bursts.
What happens to a plant when placed in a high solute concentration of liquid?
The water will leave the cells through osmosis. It will then wilt.
What happens to plants in dilute liquids?
Water enters the cell through osmosis.
This fills it up and makes it turgid.
Why don’t plant cells burst when filling with water?
Because they have cell walls
What do sports drinks contain?
- Sugars
- water
- ions
Why do sports drinks contain water and ions?
To keep the bods at homeostasis. If the concentration is disturbed cells do not work as we’ll.
Why do energy drinks contain the same concentration of ions as the body?
To not disturb the balance of concentration
What do energy drinks contain a lot of?
Glucose
What sort of concentration of ions does a rehydrating drink have in comparison to the body?
It has a lower concentration
What is active transport?
Where cells absorb substances against a concentration
What around the cell membrane allows active transport to happen?
Large protein molecules
Why does active transport require respiration?
Because it requires energy
How is energy used in Active Transport?
Energy is used to change the shape of the protein
How do proteins push an ion to the more concentrated liquid?
They change shape and this pushes them through the cell membranes
Give an example of Active Transport.
Absorption of mineral ions by root hair cells in plants
Name two ways a surface can be more effective at exchanging.
Being thin
Having a blood supply (Animals)
Ventilation (for gas exchange)
Having a large surface area
You need to do page 5-10
5-10
What is the circulatory system for?
Transporting chemicals around the body
What is the heart for?
It is mainly muscle and pumps blood around the body.
What directions do arteries go in?
Away from the heart.
What direction do veins go in?
Towards the heart
Where do pulmonary arteries and veins go?
The heart and lungs
Which goes on the top, the atria it ventricle?
The atria on top, the ventricle below
Which side of the heart has a thicker ventricle and why?
The left ventricle is large because the muscle needs to push the blood furthest
Why does blood go from the atria to the ventricle?
Because the valves open and atria contract
What do valves do?
They stop blood flowing in the wrong direction.
Describe the route of blood from the vena Cava round and back again.
Vena Cava Right atrium Right ventricle Pulmonary artery Lungs Pulmonary Vein Left atrium Left ventricle Aorta Body Vena cava
Where does the aorta pump to?
The body
Where does the pulmonary vein lead?
Left atrium
Where does the vena cava lead?
Right atrium
Which has a thinner wall- Artery or Vein?
Arteries are thicker
Why are artery walls thicker?
Higher blood pressure
Do arteries have valves?
No
Why do veins have valves?
Because veins have less pressure and need to work back up to the heart. This means that they get pushed around at each heartbeat but blood is pulled down each time by gravity. The valves close and stops this.
Why do veins have lower pressures?
Because they have spread out into capillaries where the pressure is reduced, before coming together.
Are veins or arteries closer to the surface?
Arteries are hidden mostly and veins are closer to the surface.
What are capillaries?
Very narrow and thin blood vessels covering organs
Why do arteries have muscular walls?
To create a pulse
And to maintain blood pressure
Why are arteries elastic?
To withstand high blood pressure.
What four things are blood made of?
Plasma
Red blood cells
White blood cells
Platelets
What purpose does plasma serve?
It transports CO2 to the lungs
It carries soluble products of digestion
It carries Urea
What do red blood cells have as adaptations?
No nucleus
Contain haemoglobin
They are biconcave, increasing the surface area
What is the purpose of red blood cells?
O2 binds to it at the lungs and they carry it to body parts, unwinding at various places in the body.
What is the most plentiful substance in blood?
Plasma
Do white blood cells have a nucleus?
Yes
What other system are white blood cells in other than the circulatory?
Immune System
What type ingests pathogens?
Phagocytes
What do White blood cells produce to kill pathogens?
Antibodies
What are platelets made of?
Fragments of cells
What purpose do platelets serve in protecting the blood?
They clot and stop pathogens entering
How do platelets block a wound?
They come out and coat other, along with the other cells in the blood.
They release fibrin, which makes a net like structure and clot the wound
When is artificial blood used?
When a patient has lost a lot of blood
What is the disadvantage of using plasma to replace lost blood?
Oxygen is carried less efficiently
Where can haemoglobin in artificial blood come from?
Blood of humans and cows
Gm bacteria that produce it
Placentas
What is a stent?
Tubes that can be placed in blood vessels to widen narrow vessels
What are stents made of?
Metal mesh that does not corrode
What is an artificial heart?
Devices that replace the ventricles and valves.
They pump blood
When are artificial hearts used?
When there are no donors
What do artificial valves do?
They replace diseased valves.
What limits an artificial valves life?
They eventually corrode away.
