There are two types of polymers which are natural and synthetic polymers. Natural polymers do not affect the environment but synthetic polymers do. This type of polymers are produced by humans. These release reactants which are considered hazardous to humans and the environment. Synthetic polymers include rubbers, plastics, and adhesives, and these are considered non-biodegradable and non environmental friendly. As these build up in the environment, in causes problems such as chemical poisoning to all the living things around it.
Answer:
a. different shape (e.g. flat or ribbon shaped).
d. larger internal surface area of the lungs.
Explanation:
Amphibians are cold blooded animals. They have a low rate of metabolism . Amphibians are located most where there is water or in moist environment because of their skin and how important it is to keep their skin moist.
Amphibians breathe through their skin and this can be called cutaneous respiration. Their lungs are not well developed therefore they undergo a very slow diffusion of oxygen through their blood.
For Amphibians that are larger than bull frogs, they obtain a very sufficient rate of diffusion of gases due to the following reasons:
a. Internal surface area of the lungs: Amphibians that are larger than bull frogs tend to have a more developed respiratory organs which means there lungs have a larger surface area and they are well developed.
b. They have a different body shape: Amphibians larger than bull frogs could have a flat or ribbon shape and their body shapes make it easier for respiratory gases like oxygen to permeate or enter their skin easily.
The correct answer is: a. the agar and air in the petri dish are providing all of the resources needed by the bacteria.
There are four phases of bacterial growth:
1. Lag phase-bacteria prepare for reproduction
2. Log phase- cell doubling
3. Stationary phase- due to a growth-limiting factor
4. Death phase.