Biomedical Engineering Reference
In-Depth Information
Lymph Capillaries in the Tissue Spaces
Cells
Lymph capillary
Tissue spaces
Arteriole
Venule
Tissue fluid
Lymphatic vessel
FIGURE 14.14
Lymphatic vessels embedded within the systemic capillary bed.
responsible for mass transfer of gases in one dimension and one direction. Mass transfer in
the nephron includes the movement of ions, water, and metabolic waste products, such as
urea, uric acid, and creatinine. Furthermore, the nephron initially removes more fluid and
ions than the body can safely lose. It is the mechanism by which much of this fluid and ions
are reabsorbed into the bloodstream that makes the nephron and the kidneys a unique mass
transfer system. There are millions of nephrons in both kidneys (Figure 14.15).
The nephron consists of several segments. The initial filter is the glomerulus, which is
embedded inside Bowman's capsule (Figure 14.16).
Bowman's
capsule
H
2
O
H
2
O
Na
+
Na
+
Aldosterone
Proximal
tubule
Glomerulus
Distal
tubule
Na
+
Na
+
ADH
Amino
acids
H
2
O
H
2
O
Glucose
Collecting
tubule
Loop of Henle
FIGURE 14.15
A nephron in the human kidneys.
