A model organisms is a species that has been widely studied, usually because it is easy to maintain and breed in a laboratory setting and has particular experimental advantages. model organisms are non-human species that are used in the laboratory to help scientists understand biological processes.
(
First part is explaining second part is explaining the uses)
Answer:
they have thin membranes to allow diffusion of substance for short distance
they are numerous to increase the surface area of absorption
hope this helps
It's called your Petella, although I don't know if that's how it's spelled.
Answer:
producers
Explanation:
All the energy comes from the sun. a small amount of sunlight energy is trapped by green plants and used in photosynthesis to form organic materials in plants that are sources of food to the rest of the animals. Animals get this energy when they feed on plants directly like the herbivores or indirectly like the carnivores.
Answer:
The platypus serves as a 'bridge' animal between nonmammals like birds and reptiles, which maintain their testicles in their body cavity, and placental and marsupial mammals, which hold their testes in an external scrotum."
