The communities plus abiotic and biotic surroundings is called an ecosystem
A vaccine is a substance that supports the body to produce antibodies and offer immunity in contradiction of a disease. A live attenuated vaccine comprises a version of the living microbe that has been destabilized because they are still alive this is the closest thing to an actual infection and will habitually lead the body to have a lifelong immunity after only one or two doses. A killed vaccine is created by killing the illness with chemicals, heat or radiation in which these vaccines are harmless but rouse a weaker immune reaction.
Asexual reproduction im thinking
Answer:
d.The wing-assisted incline running theory postulates that wings were initially used to maintain balance while climbing up slopes.
Explanation:
Two theories were given to explain the origin of avian flight. The top-down theory suggested that the birds' ancestors were tree dwelling species. They took help of wings to glide from tree to tree in order to avoid predator or catch prey. The bottom up theory suggested that the birds' ancestors were ground dwelling species. They took help of wings to maintain a balance and provide a lift for efficient running.
Wing-assisted incline running was a mixture of both the above theories and gave a balanced view point. According to it, birds' ancestors used wings to maintain a balance while running up inclined slopes. The wings helped them to save energy while scaling slopes and eventually a flight mechanism was also developed.
Answer:
Plants are valuable since they provide our food, materials for shelter, and purify the air (photosynthesis).
Animals such like livestock, supply us with food, fiber and leather.
The Endangered species act can help a local economy because it helps to supply clean air and pure water. It also protects our natural supplies.
