Answer:
The Laura tried to grow micro-organisms in culture broth medium in Petri-plates but the microbial growth was not observed even on the fourth day of culture which could be due to:
1. Laura could have not provided the correct broth medium maintaining the with pH and salt concentrations.
2. Microorganisms did not get optimal growth conditions.
3. The bacterial source could have died after the collection which could have lysed after their death and thus no longer visible.
Answer:
<h2>2. Peter's maternal grandfather has PKU.</h2>
Explanation:
- Such type of the genetic disorder in which two copies of a gene must be mutated at a time is called autosomal recessive disorder such as sickle cell anemia, phenylketonuria, and some other diseases.
- When a sing copy of a gene is mutated in a person then this disorder is not appeared and the person is called a carrier.
- So when a child is born by two carrier parents then there is a chance that a child will be affected if both the parents donate mutated genes.
- In the case of Peter, since peter does not show this defect this means his maternal grandfather was affected by this disorder.
The genetic fault that usually causes colour vision deficiency is passed on in what's known as an X-linked inheritance pattern.
This means:
1) it mainly affects boys, but can affect girls in some cases
2) girls are usually carriers of the genetic fault – this means they can pass it on to their children, but do not have a colour vision deficiency themselves
3) it's usually passed on by a mother to her son – the mother will often be unaffected as she'll normally just be a carrier of the genetic fault
4) fathers with a colour vision deficiency will not have children with the problem unless their partner is a carrier of the genetic fault
5) it can often skip a generation – for example, it may affect a grandfather and their grandson
6) girls are only affected if their father has a colour vision deficiency and their mother is a carrier of the genetic fault
The normal blood pH for adult humans is 7.40, and this pH value is vigorously defended at normal body temperature
Acid base Homeostasis is the method by which body keeps a constant ph
pH is kept under check via different systems
1. Chemical system :bicarbonate buffer system(explained below )
Respiratory component :
2. Respiratory Component: The second line of dense is rapid consisting of the control the carbonic acid concentration in the ECF by changing the rate and depth of breathing by hyperventilation or hypoventilation. This blows off or retains carbon dioxide (and thus carbonic acid) in the blood plasma as required
3.Metabolic component : third line of defense is slow, best measured by the base excess,eand mostly depends on the renal system which can add or remove bicarbonate ions to or from the ECF.Bicarbonate ions are derived from metabolic carbon dioxide which is enzymatically converted to carbonic acid in the renal tubular cells.There, carbonic acid spontaneously dissociates into hydrogen ions and bicarbonate ions.When the pH in the ECF falls, hydrogen ions are excreted into urine, while bicarbonate ions are secreted into blood plasma, causing the plasma pH to rise.The converse happens if the pH in the ECF tends to rise: bicarbonate ions are then excreted into the urine and hydrogen ions into the blood plasma.
Buffers usually consist of a weak acid and its conjugate base; this enables them to readily absorb excess H+ or OH–, keeping the system’s pH within a narrow range.
Maintaining a constant blood pH is critical to a person’s well-being. The buffer that maintains the pH of human blood involves carbonic acid (H2CO3), bicarbonate ion (HCO3–), and carbon dioxide (CO2). When bicarbonate ions combine with free hydrogen ions and become carbonic acid, hydrogen ions are removed, moderating pH changes. Similarly, excess carbonic acid can be converted into carbon dioxide gas and exhaled through the lungs; this prevents too many free hydrogen ions from building up in the blood and dangerously reducing its pH; likewise, if too much OH– is introduced into the system, carbonic acid will combine with it to create bicarbonate, lowering the pH.
Example: Antacids, which combat excess stomach acid, are another example of buffers.
ECF =Extra cellular fluid