Nucleotides are the building blocks of nucleic acids. In DNA, there are four types of nucleotides each containing one of four nitrogenous bases: guanine (G), cytosine (C), adenine (A), thymine (T).
- The monomer exhibited in the figure is a NUCLEOTIDE, i.e., a purine (Adenine) nucleotide.
- A nucleotide is a molecule composed of a nitrogenous base, a pentose sugar (deoxyribose in DNA) and a phosphate group.
- Purine bases consist of a double‐ring structure having four nitrogen (N) atoms and five carbons (C) atoms.
Learn more in:
brainly.com/question/919868?referrer=searchResults
Photosynthesis<span> makes the glucose that is used in </span>cellular respiration<span> to make ATP. The glucose is then turned back </span>into <span>carbon dioxide, which is used in </span>photosynthesis<span>. While water is broken down to form oxygen </span>during photosynthesis, in cellular respiration<span> oxygen is combined </span>with<span> hydrogen to form water.
</span><span>
</span>
B=the same , but a different charger
The four important characteristics of respiratory surface are:
1. Thin walls
2. Moisture
3. Large surface area
4. Blood supply
Respiratory system or respiratory tract is divided into upper and lower tract. Upper respiratory tract includes nose and its cavities, sinuses, pharynx and the part of the larynx. Lower respiratory tract consists of the trachea, bronchi, bronchioles and the alveoli.
Alveoli are the ends of the respiratory tract the smallest units in it. Alveoli are small folded air sacs that are branching off from alveolar ducts and providing an extremely large surface area for the gas exchange. Gas exchange occurs thanks to small blood vessels – capillaries that surround alveoli and it occurs via the process of diffusion.
So, respiratory surface is thin membrane also known as the blood–air barrier that consists of the alveolar epithelial cells, their basement membranes and the endothelial cells of the alveolar capillaries.
This doesn’t give enough information
