2. Transport Systems Flashcards
What are cells?
The building blocks of any living thing.
What are tissues?
Groups of cells with a similar structure and function
What are organs?
Different tissues working together
What are organ systems?
Groups of organs that perform a particular function
What are organisms?
A whole living thing
Why do large organisms need a transport system?
- absorb nutrients and respiratory gases and to remove excretory products
- transport materials between exchange surface and the cell
When is there a greater need for a specialised transport system?
When there is a lower SA/V ratio because the organism is more active
What are adaptations of red blood cells?
They have an unusual shape and are concave to give them an increased surface area
What is haemoglobin?
A large protein molecule folded around four iron atoms
Equation for oxyhemoglobin?
Haemoglobin + Oxygen = Oxyhemoglobin
What happens to haemoglobin in a high concentration of oxygen?
It reacts with the oxygen
What happens to oxyhaemoglobin in a low concentration of oxygen?
The oxyhemoglobin splits to form oxygen and haemoglobin and the oxygen diffuses to where it’s needed
What is plasma?
The clear liquid of blood that remains after red blood cells are removed
What does plasma contain?
Water, salts, antibodies and other proteins
What is plasma for?
It’s a transporting medium for cells and a variety of substances
What does plasma help carry out?
Blood clotting, fighting diseases
What do white blood cells do?
Engulf then digest pathogens
What are pathogens?
Microbes that cause disease
What can white blood cells produce?
Antibodies and antitoxins
What are platelets?
Small fragments of cell which are important in blood clotting
What direction do arteries carry blood?
Away from the heart
What direction do veins carry blood?
Towards the heart
Which has a pulse : arteries or veins?
Arteries
What do valves do?
Prevent the back flow of blood as it moves from the body to the heart
What are capillaries?
Blood vessels that form a network between arteries and veins
What artery takes blood to the rest of the body?
Aorta
What vein takes blood from the body to the heart?
Vena cava
What blood vessel takes oxygenated blood towards the heart?
Pulmonary vein
What blood vessel takes deoxygenated blood towards the lungs?
Pulmonary artery
What blood vessel takes blood into the kidney?
Renal artery
Why are capillaries narrow?
- nutrients can reach cells of organs
* blood flow is slowed down and blood pressure is lowered
What is the job of the circulatory system?
To transport blood containing substances such as oxygen around the body
What do coronary arteries supply the heart with?
Oxygen and glucose for respiration
Why is the cardiac muscle of the left ventricle thicker than the right?
It needs to create pressure to pump the blood around the body whereas the left only has to take it to the lungs
What are artificial pacemakers?
Electrical devices that are used to correct irregularities in heart rate
Why are the alveoli good for gas exchange?
- very thin walls make diffusion easy
- moist surface makes diffusion easy as gases dissolve
- spherical shape gives relitavely large surface area for diffusion
What does the breathing system do?
Takes air in and out of the body
What pH is oxygen?
neutral , 7
What pH is CO2?
Acidic,
What are the muscles between the ribs called?
Intercostal muscles
What happens to the pressure as the volume inside the chest increases?
It decreases
What is a stent?
A metal mesh that is placed in the artery
How does a stent open up a blood vessel?
A tiny balloon is inflated to open up the blood vessel and the stent
Advantages/ disadvantages of mechanical valves?
They last for a long time but you have to take medicine
Advantages/ disadvantages of biological valves?
They work well and the patient doesn’t need medicine but they only last for about 15 years
What is coronary heart disease?
Fatty deposits in the walls of the coronary arteries reducing the supply of oxygen to heart muscle
What enzyme does the mouth contain?
Salivary amylase
What does the liver do?
Makes bike
What does the gall bladder do?
Stores bile
What does bile contain?
Bile salts and alkali
What does the stomach squirt on food?
Hydrochloric acid
What enzyme does the stomach produce?
Gastric protease (pepsin)
What enzymes does the pancreas produce?
Pancreatic protease (trypsin)
Pancreatic amylase
Pancreatic lipase
What does the pancreas produce as well as enzymes?
Alkali
What enzymes does the small intestine produce?
Lipase, protease and carbohydrases
What are the two types of carbohydrase that the small intestine produces?
Amylase and Maltese
What do protease enzymes do?
Digest proteins to amino acids
What do lipase enzymes do?
Digests fats or lipids to fatty acids and glycerol
What do amylase enzymes do?
Digests starch to sugars
Where is bile released?
On the food in the small intestine
What does bile do?
Emulsifies lipids from large fat droplets with a small surface area
What does bile NOT contain?
Enzymes
Why does bile emulsify fats?
So that they have larger surface areas so they can be digested quickly and efficiently by lipase enzymes
Why does bile contain alkali?
To provide optimum pH for the action of enzymes
What is absorbed into the blood through the walls of the small intestine?
Small, soluble products of digestion (sugars and amino acids)
What are the small intestines adaptations for absorption?
Villi
Good things about villi?
- they have a rich blood supply for a steep concentration gradient and quicker diffusion
- large surface area
- thin wall so there is a short distance for diffusion to take place
- they have microvilli
What process absorbs nutrients into the blood through the wall of the small intestine?
Active transport