The first organisms to inhabit Earth were prokaryotes that
lived 3.5 billion years ago. prokaryotes are well organised, achieving all of an organism’s life functions
within a single cell. These were the precursors to eukaryotic cells
Answer:
The correct answer will be option D (they are complementary).
Explanation:
Complementary DNA or cDNA is an edited DNA molecule synthesized from a single-stranded RNA called mRNA. The reaction of cDNA formation from mRNA is catalyzed by an enzyme called "reverse transcriptase".
The cDNA strands formed is also known as a complementary copy of mRNA as it contains no introns or non-coding sequence in its sequence similar to mRNA. cDNA is used in recombinant DNA technology to clone eukaryotic genes in prokaryotes.
Thus, option D (they are complementary) is the correct answer.
Answer:
The <u>PCO₂</u> -carbon dioxide partial pressure- in the alveoli is 40 mm Hg and that of the blood entering the pulmonary capillaries is <u>45 mmHg</u>. This causes <u>carbon dioxide</u> to diffuse down its partial pressure gradient from the blood into the alveoli.
Explanation:
Gas exchange is a physiological process that involves the entry of oxygen into the body and tissues and the exit of carbon dioxide, a product of metabolic reactions.
At the pulmonary level, gas exchange occurs between the alveoli and the alveolar capillary, and the diffusion of gases across the alveolar-capillary barrier is dependent on a pressure gradient due to the partial pressure of gases.
In the case of CO₂ the diffusion goes from where the partial pressure is higher to where it is lower, i.e. <u>from the alveolar capillary, where the PCO₂ is 45 mmHg, to the pulmonary alveolus, where the PCO₂ is 40 mmHg</u>.
Learn more:
Gas exchange brainly.com/question/4469204