Answer:
The sun is important for many reasons. Even though its far away, it keeps us warm, and gives us light. Plants also need the light to survive, and we need plants to breathe and to eat. We also need the sun because it makes sure the earth goes were its supposed to in space
Explanation:
Heterocyst-forming cyanobacteria differentiate highly specialized cells to provide fixed nitrogen to the vegetative cells in a filament. In the presence of a source of combined nitrogen such as nitrate or ammonium, Anabaena PCC 7120 grows as long filaments containing hundreds of photosynthetic vegetative cells.
Virus are made with ADN or RNA only, which both of them has the information of replication. Once that the virus is in a cell, this ADN or RNA will be deposit inside the cell at the replication system that is going to make the virus reproduce unlimited times until the membranes of the cell break down. And they are useful because you can use them as a carrier or vector for treat diseases or for transgenics, bioterrorism, and so on.
Answer:
Replacing skin defects has witnessed several developments over the centuries. It started with the introduction of skin grafting by Reverdin in 1871. Since then, varieties of skin grafting techniques have been used successfully. Despite being clinically useful, skin grafts have many limitations including the availability of the donor site especially in circumstances of extensive skin loss, immune rejection in allogenic skin grafts, pain, scarring, slow healing and infection.1,2 For these reasons, scientist have worked hard to find skin substitutes to replace skin defects without the need for a "natural" skin graft. These materials which are used to cover skin defects are called "Skin substitutes". This article briefly discusses the common types of skin substitutes and their clinical uses.
Answer:
Species are adapted to their environments. By understanding the interactions within an ecosystem, scientists can develop an understand of how populations evolve (develop gradually) in response to their environment.
