Answer:
True. You can get vitamin A as "preformed vitamin A" which is already active and/or you can get vitamin A as carotenoids which the body can turn into active vitamin A.
Explanation:
There are two different types of vitamin A that can be obtained from food:
1. Preformed vitamin A, which is already active, is found in animal products such as beef, fish, poultry and dairy products.
2. Provitamin A, which is the inactive form, is found in plant-based foods, such as fruits and vegetables. The most common type of provitamin A is β-carotene, which is a carotenoid that the body can turn into active vitamin A via an enzyme named β-carotene 15,15'-monooxygenase.
Mitochondria - The mitochondria is referred to as the power house of the cell. Its main function if to produceenergy for cell by the process of cellular respiration. The energyproduced is ATP. Endoplasmic Reticulum - It is a network for transportation of certain substances in and out of the nucleus.
DNA replication needs to occur because existing cells divide to produce new cells. Each cell needs a full instruction manual to operate properly. So the DNA needs to be copied before cell division so that each new cell receives a full set of instructions!
