Question

1. What are the two types of nutritional transport and describe the similarities and differences between them.

2. What is tonicity and what impact does it have on microbial survival.

3. What are four associated with the utilization of oxygen for microbial growth.

4. What are the metabolic pathways involved in the Metabolism of glucose and what are the energetic associated with each pathway.

5. What are the five types of eukaryotic cell after terminal evolution.

6. Identify the unique features of the five eukaryotic cell types that can be used to distinguish each one from the other.

Answer 1

1. Nutrient transport is a process by which nutrients gets tranported within the body of an organism. There are usually two types of nutrient transport process available: Active transport and Passive transport.

Similarities:

• Both involve ion movement
• Both use ion channels to move ions across the cell membrane

Differences:

Active transport	Passive Transport
Active Transport uses ATP to pump molecules against the concentration gradient.	Movement of molecules down the concentration gradient.
Transport occurs from a low concentration of solute to high concentration of solute	It goes from high to low concentration, in order to maintain equilibrium in the cells
Example: phagocytosis, pinocytosis, sodium/potassium pump,	Example: diffusion, osmosis, and facilitated diffusion.

2. Tonicity is defined as the ability of an extracellular solution to make water move into or out of a cell by osmosis. The tonicity of a solution is related to its osmolarity, which is the total concentration of all solutes in the solution. A solution with low osmolarity has fewer solute particles per liter of solution, while a solution with high osmolarity has more solute particles per liter of solution.

According to tonicity, three type sof solutions exist: Hypertonic, Isotonic and hypotonic. If a cell is placed in a hypertonic solution, water will leave the cell, and the cell will shrink. In an isotonic environment, the relative concentrations of solute and water are equal on both sides of the membrane. There is no net water movement, so there is no change in the size of the cell. When a cell is placed in a hypotonic environment, water will enter the cell, and the cell will swell.