Answer:
Due to presence at early days of the planet.
Explanation:
We only find the remains of single celled organisms in the oldest fossils because the single celled organisms are the organisms that were present in the early days of this planet. These single celled microbes were present about 3.7 billion years ago while on the other hand, the oldest rocks are only a little older i. e. 3.8 billion years so these single celled organisms are considered as oldest fossils on this planet.
Answer:
Increase aldosterone and decrease ADH
Explanation:
Aldosterone causes reabsorption of sodium ions while Antidiuretic hormone (ADH) causes reabsorption of water. Aldosterone also causes water reabsorption due to increased osmotic pressure by reabsorbing sodium ions. But for water reabsorption, Aldosterone has to work along with ADH to increase permeability for water. If we increase Aldosterone and decrease ADH, the sodium ions will be reabsorbed while water cannot be reabsorbed due to decreased permeability of DCT and collecting tubules for water.
The doctor is higher class, kino's lower class, kino became scared because he had to trust the doctor to sure his son.
Answer:
E. that area of the membrane is in the absolutely refractory period.
Explanation:
Refractory period is a period during which neuron cell cannot be stimulated (depolarized). This is why the action potential can only travel in one direction from the neuron body towards axon.
Refractory period occurs because of the inactivation of voltage-gated sodium channels (while action potential is at its peak) which cannot be open for a certain period of time. and membrane cannot be depolarized.