If I’m not mistaking it’s the 2nd one plant cell
Answer: Layer a is 500 million years old.
Explanation:
Trilobite is a member of the group of extinct arthropods found as fossils and they can be identified by the three-lobed as well as three segmented forms. These were the marine animals. These were appeared initially in the Cambrian Period. They used to live 542 million years ago so the fossils can be estimated to be aged of 500 above years old. These animals used to dominate in the sea area.
Answer: option D
The sodium potassium ion exchange move sodium and potassium in opposite direction in electrochemical gradients.
Explanation:
The sodium potassium pump is found in many animals plasma membranes and its moves the sodium and potassium ion in opposite direction across the plasma membrane with the hydrolysis of ATP(adenosine triphosphate) to supply the needed energy. It is an active transport process.
