Answer:
The tail and the caudal fin are the chief locomotory organs of fish and are used for rapid swimming during which tail is lashed from side to side by "alternate contraction and relaxation" of the myomeres on the two sides of the vertebral column.
Explanation:
The nucleus is the right answer BOOOF
Answer:
The hydrophobic core of the membrane does not allow the charged particles to pass through it.
Explanation:
The inner core of the membrane is made up of hydrophobic fatty acid tails of phospholipids. Due to this, some substances such as large, charged and polar particles cannot cross the membrane. This is why Na+ with a positive charge cross the membrane with the help of transport proteins only. On the other hand, molecular oxygen (O2) has a small structure and does not carry any charge. Therefore, it can cross the membrane without any help of transport proteins.
A is the corect answer ! I hope this helped !