Mass transport in animals Flashcards
What is plasma?
The liquid component of blood
What are the 4 components of blood?
- White blood cells
- Red blood cells
- Plasma
- platelets
Define mass transport
The bulk movement of liquids or gases in one direction, usually through a system of tubes or vessels
When centrifuged what is closest to the bottom?
Red blood cells are at the bottom with white blood cells above them and then plasma at the top. Plasma is about 55% white blood cells and platelets are less than 1% and red blood cells are around 45%
What does plasma do?
Plasma allows blood to flow and therefore has to be a large proportion of blood. This means the heart has to work less hard
The heart is a double pump, where does it pump blood to?
The left half of the heart pumps to the tissues while the right pump to the lungs
Where do veins flow?
Veins move blood towards the heart
Where do arteries flow?
Arteries (away) move blood away from the heart.
Properties of arteries:
- thick flexible walls to withstand pressure
- 3 layer walls - the middle is elastic - outside is strong
- the endothelium is smooth to reduce friction
Why are the elastic walls in arteries important?
The elastic walls can expand and contract to allow better maintenance of pressure, to make it easier for the heart to pump. It means blood flow can be kept constant.
Properties of veins:
- much thinner walls than arteries as blood pressure is lower and blood moves slower
- less elastic than arteries
- there are valves in veins to stop the backwards flow
Epic fact
The capillaries are around 100km long when stretched out
Properties of capillaries:
- expansive networks for surface area
- very thin walls for rapid diffusion
What is in capillaries?
- Lumen
- nucleus
- endothelial cell
- junction between cells
- capillary wall
What is an epithelium?
(OUTSIDE) the thin tissue forming the outer layer of a body’s surface and lining the alimentary canal and other hollow structures.
What is an endothelium?
(INSIDE) The tissue which forms a single layer of cells lining various organs and cavities of the body, especially the blood vessels, heart, and lymphatic vessels. It is formed from the embryonic mesoderm.
What do capillaries thin walls allow?
Due to capillaries, thin walls fluid may leak out between the cells. It means oxygen, carbon dioxide, glucose, amino acids and hormones can move through
What is tissue fluid?
A fluid surrounding cells that are formed from blood plasma without large proteins. It is the immediate environment of each cell. TBC
What is hydrostatic pressure?
Pressure caused by an increased volume of fluid inside a vessel.
What is a lymph capillary?
A vessel that helps to drain tissue fluid and return plasma proteins to the blood via the lymphatic system.
What is elephantiasis?
An illness when parasitic worms block lymph vessels which clear fluid. It, therefore, causes extensive swelling.
How are red blood cells adapted to transport oxygen?
- They have a small size allowing them to fit through narrow capillaries
- their flattened disk shape allows for a large surface area to volume ratio
- they are flexible so they fit through small spaces
- they lack organelles allowing maximum space for haemoglobin
- they contain plasma allowing constant movement
Haemoglobin properties:
Haemoglobin has a quarternary structure protein it consists of four polypeptides called globins which have haem in the middle of each. Haem is the key to oxygen-carrying in haemoglobin. Iron molecules can easily combine with oxygen so haem contains iron allowing it to easily pick up oxygen and drop it off.
Different kinds of haemoglobin:
There are several different types of globin chains, named alpha, beta, delta, and gamma. Normal haemoglobin types include: Hemoglobin A (Hb A): makes up about 95%-98% of haemoglobin found in adults; it contains two alpha (α) chains and two beta (β) protein chains
What is oxyhaemoglobin?
The complex formed when haemoglobin binds to oxygen.
Haemoglobin pressure
TBC p162
What is the function of the heart?
The heart pumps blood around the body, it has two halves: one half pumps blood to the lungs where its oxygenated and the other returns it to the heart where it’s pumped to the other organs
What is the average resting heartbeat?
60-70 BPM
How long can the brain go without oxygen?
5-6 minutes and then brain cells will begin to die
What are the lower chambers in the heart called?
The lower chambers are the ventricles
What are the upper chambers in the heart called?
The upper chambers are the atria
What is the job of the atria?
To collect blood and pump it into the ventricles.
what is the structure of haemoglobin
globular
how many chains are in haemoglobin
4
what are the chains
2 beta pleated sheets and two alpha helix
What is an affinity?
Specifically, the oxyhemoglobin dissociation curve relates oxygen saturation (SO2) and partial pressure of oxygen in the blood (PO2), and is determined by what is called “hemoglobin affinity for oxygen”; that is, how readily hemoglobin acquires and releases oxygen molecules into the fluid that surrounds it.
What is haemoglobin?
Haemoglobin is found in red blood cells and carries oxygen efficiently from the lungs to the tissues in body. It also aids in transporting hydrogen ions and carbon dioxide back to the lungs. Haemoglobin is capable of binding to oxygen (O2) and gaseous nitric oxide (NO).
What effect does temperature increase have on affinity of haemoglobin?
Temperature increase reduces haemoglobin affinity for O2 and so more O2 is delivered.
What effect does blood pH lowering have on affinity of haemoglobin?
Blood pH lowering causes the presence of H+ ions and reduces the affinity for Haemoglobin for O2
What effect does raising carbon dioxide have on affinity of haemoglobin?
Higher carbon dioxide concentration in tissue causes less affinity of Hb for O2 so more O2 is released.
What is pO2?
pO2 is the partial pressure of oxygen concentration.
