Answer:
El proceso de la fotosíntesis se divide en dos etapas, la primera llamada "Lumínica" o fotodependiente y la segunda "Oscura" o fotoindependiente.
Explanation:
A closed system is a system that makes no physical or chemical exchanges with its environment. Of these systems provided as choices (tree, human, clock, car), only a clock does not make exchanges with the environment, except for energy.
Therefore, of that list, only a clock would be a closed system.
Hope that helped! =)
The answer is; D
Carbon dioxide and methane are potent greenhouse gases. They cause heating of the lower atmosphere, by trapping sunlight, that results to climate change. Due to the higher melting and boiling temperatures of phosphorus, it is rare that it occurs as gas in room temperatures. Phosphorus, therefore, does not pose a great threat of climate change.
Cell has cell membrane<span> (also known as the </span>plasma membrane<span> or </span>cytoplasmic membrane<span>) it is a </span>biological membrane<span> that separates the </span>interior<span> of all </span>cells<span> from the </span>outside environment.<span> The cell membrane is </span>selectively permeable<span> to </span>ions<span> and </span>organic molecules<span>and </span>controls the movement of substances<span> in and out of cells.</span><span>The basic function of the cell membrane is to protect the cell from its surroundings.</span>
Answer:
c. If the double helix were unwound, each nucleotide along the two parent strands would form a hydrogen bond with its complementary nucleotide.
Explanation:
According to the Watson-Crick model, two DNA strands are held together by complementary base pairing wherein each nucleotide of one DNA strand forms hydrogen bonds with its complementary nucleotide present in the other strand. During DNA replication, two DNA strands are separated by the action of helicases enzymes.
The separated DNA strands serve as a template for DNA replication. Here, each nucleotide of the template DNA strand binds to its complementary nucleotide by hydrogen bonds. For example, adenine of the template strand forms two hydrogen bonds with thymine while guanine forms three hydrogen bonds with cytosine.