A peptide bond is a chemical bond<span> formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water (H2O).
Source; </span>https://www.sciencedaily.com/terms/peptide_bond<span>.htm</span>
Tears and mucous membrane are part of the General defense
system. The General defense system of the body consists of the skin, clotting,
sweat glands, lysozyme, mucous membranes, nasal hairs, cilia, hydrolic acids,
and the vagina. General defense systems have a vital role in giving barriers to
stop bacteria in entering our body which will make us sick.
Answer: Glial cells called ASTROCYTES help maintain the blood-brain barrier, whereas SCHWANN CELLS create the myelin that envelopes axons
Explanation: Glial cells are specialized cell that are found in both central and peripheral nervous systems, that surrounds the neurones, providing them with support and insulation. There are different types of Glial cells these includes:
- Astrocytes: they maintain the blood brain barrier.
- Schwann cells: create the myelin that envelopes axons of the peripheral nervous system neurones.
- satellite cells: These cells help regulate the external chemical environment of neurones.
- Microglia: they clean up cellular debris through phagocytosis.
- Oligodendrocytes: create the myelin that envelopes axons of the central nervous system
<span>9 kilocal per gram of fat 21 grams of fat*9 kilocal per gram of fat = 189</span>
The question is incomplete. The complete question is attached below.
Answer:
1. DNA is the polymer of deoxyribonucleotides that contain the nitrogenous base, pentose sugar and phosphate group. The phosphate is attached with the 3 C position of the deoxyribose sugar. This leads to teh formation of phosphodiester bond.
2. The DNA backbone consists of phosphate and sugar. The nitrogenous bases are inserted inside the DNA molecule. These nitrogenous bases are linked together by the hydrogen bonds.
3. The adenine binds requires two hydrogen bonds to bind with thymine. This provide complementary nature to the DNA molecule. Uracil is present instead of thymine in RNA .
4. The guanine binds requires three hydrogen bonds to bind with cytosine. More amount of energy is required to break their bonds.