Answer:
SA node
Explanation:
The SA node (called the pacemaker of the heart) sends out an electrical impulse. The upper heart chambers (atria) contract. The AV node sends an impulse into the ventricles. The lower heart chambers (ventricles) contract or pump.
Answer:
What impact does a decrease in pH have on urchins?
Decrease in pH simply means high degree of acidity which affects every living organism. The impact of high acidity affects there food intake, development of their young ones (juvenile)
Explanation:
Answer:
- Water entered the potato strips because the potato cells contained higher concentration of solutes than its external environment.
- The solutions are hypotonic to the solution in the potato cells.
Explanation:
According to osmosis, water will move from a region where it is high in concentration to that region where it is low in concentration. However, a region with high solute concentration contains a low water concentration and vice versa.
Hence, according to this question, water is said to move into potato strips from solutions of molar concentrations like 0.0M, 0.2M etc. Water moved into the potato strips because potato cells contained higher concentration of solutes than its external environment. This means that the external solutions are HYPERTONIC i.e. low in solute concentration to the solution in the potato strips.
It's letter c i believe, because they need the DNA's instruction on how to copy the exact tissue copy.
