Topic 8: Transport in Mammals Flashcards
Basophil
A white blood cell which produces histamine to stimulate the repair of damaged tissue through inflammation.
Esinophil
A white blood cell which combats allergic reactions.
Hydrostatic Pressure
Pressure which is due to a liquid. When blood is under high hydrostatic pressure some of the liquid part of the blood, plasma, is pushed through the epithelium and into the tissue fluid.
Lymph
An Almost colorless fluid, very similar in composition to blood plasma but with fewer plasma proteins, that is present in lymph vessels
The part of the tissue fluid which drains into the lymphatic vessels. It has the same composition as tissue fluid but it also contains fat droplets.
Neutrophil
A white blood cell which is phagocytic on pathogens. Comprises 70% of total white blood cells.
Oedema
A swelling condition in humans which results when there is an imbalance in the rate of production of tissue fluid and the rate of water reabsorbtion into the blood
Osmotic Pressure
Osmotic pressure is the minimum pressure which needs to be applied to a solution to prevent the inward flow of water across a semipermeable membrane. It is also define as the measure of tendency of a solution to take in water by osmosis. Water moves from a region of high water potential (low solute concentration) to a region of low water potential (high solute concentration)
Subclavian Vein
The vein in the neck which the lymph drains into and joins the circulatory system.
Tissue Fluid
The almost colorless liquid that fills the spaces between body cells; tissue fluid forms from the fluid that leaks from the blood capillaries, and most of it eventually collects into lymph vessels where it forms lymph.
This is the fluid that bathes the body cells. It is formed from ultrafiltration of the blood plasma in the arteriole end of the capillary bed.Tissue fluid provides cell essential materials such as glucose and removes waste such as CO2. It also keeps the temperature and the composition of cells fairly constant to maintain a constant environment through homeostasis. The Moisture that tissue fluid provides around cells allows gas exchange into and out of the cells.
Tunica Externa
The ‘outer coat of an artery or vein - Contains collagen and some elastic fibres.
Tunica Intima
The ‘inner coat of an artery or vein - A single layer of squamous epithelium cells
Tunica Media
The ‘middle coat’ of an artery or vein - Contains elastic fibres, collagen, smooth muscle.
Ultrafiltration
Filtration on a molecular scale e.g. the filtration that occurs as blood flows through capillaries, especially those in glomeruli in the kidney.
The process of filtration under high pressure. It occurs when small molecules in the blood pass through the squamous epithelium into the tissue fluid.
Water Potential
This is the measure of the kinetic energy of water molecules. water molecules are constantly moving in a random fashion. Some water molecules collide with the cell membrane, creating a pressure on it known as the water potential. Water moves from a region of higher water potential to a region of lower water potential.
