Which of the following substances is not normally found in filtrate?
a. water and small solutes
b. blood cells and large particles
c. ions, such as sodium and potassium
d. nitrogenous waste particles, such as
urea

blood cells and large particles.

Explanation:

Filtrate is the fluid that is filtered from the blood which pass through the nephron. When blood flows from the nephron, it enter the Bowman's capsule of the glomerulus. The tiny walls of the glomerulus can only allow the passage of small particles or is not selectively permeable to small particles such as water, ions ,sodium, potassium, nitrogenous wastes. Larger molecules and blood cells stay in the blood vessels because they cannot pass through the tiny walls

a- all cells come from pre-existing cells

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.