The injection would be to keep him from getting infections
The first living things on Earth, single-celled micro-organisms or microbes lacking a cell nucleus or cell membrane known as prokaryotes, seem to have first appeared on Earth almost four billion years ago, just a few hundred million years after the formation of the Earth itself.
1. courtship rituals 2. attract a mate 3. internal fertalisation occurs inside the feamales body whereas external fertalisation occurs outside the feamales body 4. <span>Gametes may get washed away 5. the devoloping zygote is protected</span>
Answer:
It means that the cell membrane allows certain substances to pass through and not others. As the cell membrane consists of a phospholipid bilayer with a hydrophobic core, only small uncharged hydrophobic molecules can pass through the cell membrane e.g. glucocorticoid and other larger charged particles require transporters or channel proteins to pass through the cell membrane, e.g. glucose.
Answer:
Due to less steps and requires less energy.
Explanation:
The bacterial cell is able to use glucose first as an energy source then switch to lactose because glucose requires less steps and less amount of energy for the break down as compared to lactose. If lactose is the only sugar available to the bacterial cells, then bacterial cells will use it as energy source for the production of energy. In order to use lactose, the bacteria must express the lac operon genes, which encode the main enzymes for lactose uptake and metabolism.
