Answer:
Bicarbonate ion, HCO3- (which has a similar charge to chloride ions) also follow sodium ions into the blood. Also, potassium ions, K+ are transported into the nephron so some chloride ions and bicarbonate ions remains in the nephron to balance the charge.
Explanation:
Sodium is the primary positively charged electrolyte in extracellular fluid. Most of the solute reabsorbed in the proximal tubule is in the form of sodium bicarbonate and sodium chloride. Water is also reabsorbed in order to balance osmotic pressure
When sodium ions are reabsorbed into the blood, few of the substances that are transported with Na+ on the membrane facing the lumen of the tubules include Cl- ions, Ca2+ ions, amino acids, and glucose. Sodium is actively exchanged for K+ using ATP on the basal membrane.
In the distal convoluted tubule, K+ and H+ ions are selectively secreted into the filtrate, while Na+, Cl-, and HCO3- ions are reabsorbed to maintain pH and electrolyte balance in the blood.
Some chloride ions remains in the nephron to balance the charge of the secreted K+ ions and also due to the bicarbonate ions that are removed.
Answer:
tertiary; quaternary
Explanation:
The orientation of all the atoms of a protein in three dimensions represents its tertiary structure. It includes the folding of the polypeptide chains in a way that brings are far apart amino acids of its secondary structure close together. Various segments of a polypeptide chain interact to form tertiary structures and these segments are held together by different kinds of weak interactions.
However, disulfide cross-links between the segments of polypeptide chains also stabilize the tertiary structure of some proteins. Likewise, disulfide bonds also hold the protein subunits of some proteins together and thereby, contribute to the quaternary structure. For example, two light chains of an antibody are joined together by disulfide bonds.
Answer:
1. Radiometric dating
2. Relative dating is used to determine the age of fossils or rock layers by by comparing it to similar rocks and fossils of known ages.
3. The youngest rock layers are at the top and the oldest are at the bottom, which is according to the law of superposition.
4. Tribolite and Pecten fossils
Fossils are used to determine the ages of rock layers. Index fossils are the most useful in determining relative aging. Index fossils are of organisms that lived for a short period of time. An index fossil allows a scientist to determine the age of the rock it is in. So if they are found in a particular age, it means they belong in that age.
5. Scientists commonly use radioactive dating methods by using radioactive decay cloak of certain elements such as potassium or carbon to date fossils or rocks.
6. Law of superposition because in terms of finding the age of the rock as an object, all that needs to be identified are the layers of the rock.
7. The nuclear decay of radioactive elements are a process that behaves in a clock-like fashion which makes it a useful tool for determining the exact age of fossils or rocks.
The probability that a homozygous recessive individual would be producing a dominant allele would be 0%. If expressed as a percentage, this is because the individual does not even have the possible allele in its genotype for whatever trait or feature that the protein codes for.
