Answer:
Growth factors
Explanation:
Growth factors, unlike hormone, have an influence on most cells on the body. They promote cell division and differentiation. Therefore, they are significant in promoting the cell cycle. Therefore, they should be able to be recognized by checkpoint proteins that regulate the cell cycle by either promoting progression or arresting the cell cycle.
Answer;
Semi-permeability means that only certain molecules are allowed to pass through.
Explanation;
-Semi-permeability is one of the features of a cell membrane, which means that the membrane allows selective movement of materials in and out of the cell; that is only certain molecules can enter or leave the cell.
-For example smaller molecules such water and ions such as potassium and sodium ions are able to leave and enter the cell, while other molecules that are large such as protein molecules can not enter or leave the cell.
Answer:
Pteridophytes are vascular plants but they do not produce flowers and seeds which mean their source of reproduction is unknown or hidden.
On the contrary, Spermatophytes as the name indicates, are seed bearing plants. They produced seeds and flowers. Examples are flowering plants, cactus, leather flower, buttercup and may more.
Explanation:
