Organising Animals and Plants Flashcards
What are the 4 components of the blood?
Plasma, red blood cells, white blood cells and platelets
Describe the function of blood plasma, and give an example
To transport substances around the body
e.g. waste CO2 being carried to the lungs
What is the function of a red blood cell?
Transport O2 around the body and deliver to where it’s needed
Give 3 adaptations of red blood cells
- Bioconcave disc shaped, allowing for a larger surface area to volume ratio for diffusion
- Packed with a red pigment called haemoglobin which
binds to O2 - Have no nucleus to provide more space for
haemoglobin
Give the word equation for the bonding of oxygen and haemoglobin
Haemoglobin + Oxygen —– Oxyhaemoglobin
Describe the function of white blood cells
Form part of the body’s immune system to destroy pathogens
Describe the function of platelets
They help blood to clot around a wound and form scabs so that bacteria cannot enter the wound.
What are the pros and cons of donating blood?
Pros:
- Can replace blood lost in injury
- Some people are given platelets extracted from blood
to assist clotting
- Proteins extracted from blood can be used to make
antibodies
Cons:
- In a blood transfusion, the donor’s blood must be the
same type as the patient’s, or the patient’s immune
system will reject the donated blood and could possibly
die
- Many diseases can be transmitted through blood
Do arteries carry blood to or away from the heart?
Arteries carry blood away from the heart to the organs in the body ( art sounds like OUT)
Describe and explain the properties of arteries
They have a small lumen, and thick muscular walls to withstand the high pressure of the oxygenated blood that they’re transporting
Where is blood transported to after the arteries?
The capillaries
Describe what happens to blood at the capillaries
Substances such as glucose and oxygen diffuse from the blood into body cells, while CO2 diffuses from the body cells into the blood inside the capillaries
Describe and explain the properties of capillaries
They have thin walls that are one cell thick so that the diffusion pathway is short and quick, allowing substances to diffuse rapidly between the blood and body cells
Where does blood go after it’s travelled through the capillaries and body cells?
The veins
Do veins carry blood away or back towards the heart?
Back towards the heart ( ve-IN)
Describe the properties of Veins
They have thin walls and a large lumen because the blood is at a lower pressure
Describe the blood flow once the blood is in the veins
Blood is deoxygenated and at low pressure
What mechanism is in place to stop the backflow of blood once inside the veins?
Valves
What is the function of valves?
To prevent the backflow of blood
What is the benefit of a double circulatory system rather than a single one?
Blood travels through the heart twice, meaning it can travel faster around the body and to the body cells
What are the top chambers of the heart called?
The atria
What blood vessel brings deoxygenated blood from the body to the heart?
The Vena Cava
What blood vessel pumps deoxygenated blood to the lungs?
The Pulmonary artery
What blood vessel brings oxygenated blood from the lungs back to the heart?
The Pulmonary vein
What blood vessel pumps out oxygenated blood to the organs and body cells?
The aorta
Describe the pathway of blood in the human body
-Deoxygenated blood is brought into the heart via the Vena Cava, through the right atrium and down the right ventricle. The ventricle contracts and blood is pumped through the Pulmonary artery to the lungs. The blood collects oxygen and returns to the heart through the Pulmonary Vein. The blood then goes through the left atrium and ventricle, then is pumped out through the Aorta to the organs and body cells.
What are the purposes of valves in the heart?
They prevent backflow of the blood from the atria into the ventricles when the ventricles contract
Why does the left side of the heart have a thicker muscular wall than the right?
The left side of the heart pumps blood around the whole body, and therefore needs to provide more force, while the right side only pumps blood to the lungs
What are the Coronary arteries?
An important type of blood vessel that branch out of the aorta and spread into the heart muscle
- they supply the heart with oxygenated blood
What is the purpose of the Coronary Arteries?
To provide O2 to the muscle cells of the heart, which is used to provide energy for the heart to contract
What is the resting heart rate controlled by?
A pacemaker
What is an artificial pacemaker?
A small electrical device that corrects irregularities in the heart rate