A good passing current is a small wave for example.
Answer:
e. secretion, absorption and chemical protection
Explanation:
Epithelial tissues is responsible for the protection of the skin, absorption of nutrients during digestion and secretion of waste materials. These tissues form covering to all body surfaces. They also perform a variety of other functions such as excretion of waste substances, filtration of air from dirt and particles and clean the air that is inhaled, diffusion, and sensory reception.
Airborne nitrogen is one of the largest sources of pollution affecting the Chesapeake Bay and its tributaries. Excess nitrogen can fuel the growth of algae blooms, which can block sunlight from reaching underwater grasses and create low-oxygen “dead zones” that suffocate marine life.
The benefits of the biotechnological researches posses the same level of threat if they are not regulated. It is essential to set some ethical guidelines to prevent the misuse of the biotechnological researches. the genetically altered organisms posses a harm to the environment if they are mixed with the natural occurring ones. Moreover, the super pathogens and drugs can cause a catastrophe if not handled properly, and can be used in bio-terrorism. Hence, it is essential to follow the rules and take in notice the ethical concerns.
It has 3 layers
an animal cell has no cell wall but a plant cell dose
it protects,support, and gives the plants their shape
