Answer: Subsistence agriculture.
Explanation: Subsistence agriculture is a type of farming in which farmers cultivate and grow food crops and livestocks to meet their needs and that of their family.
In this type of agriculture, farm products is aimed to survival and it doesn't involve use of large-scale irrigation, chemical fertilizer, or machinery and technology.
Answer:Action potentials result from the depolarization of the cell membrane (the sarcolemma), which opens voltage-sensitive sodium channels; these become inactivated and the membrane is repolarized through the outward current of potassium ions.
its 'b'
Explanation:
Mutation is the primary cause of all genetic variation. Mutation is important as the first step in evolution, as it produces a new sequence of DNA for a particular gene, producing a new allele. Recombination, through intragenic recombination, may also generate a new DNA sequence (a new allele) for a particular gene.
Nephron helps the urinary system to rid off metabolic waste in our system.
