Blood

The correct answer is:

Option 2: decrease the affinity of hemoglobin with oxygen

Explanation:

The pH of blood plays a crucial role in the ability of hemoglobin to bind to oxygen. This is governed by the Bohr effect, which describes how changes in blood pH affect oxygen binding to hemoglobin.

Bohr Effect: When the pH of blood decreases (i.e., becomes more acidic), it causes a decrease in the affinity of hemoglobin for oxygen. This means that hemoglobin will release oxygen more readily to tissues that are actively metabolizing and producing more CO2 (which lowers the pH).

Why the Other Options Are Incorrect:

Option 1: While a decrease in pH can affect oxygen delivery, it does not directly reduce the blood supply to the brain. The body adjusts by increasing respiratory rate to remove CO2, which helps regulate blood pH.

Option 3: The release of bicarbonate ions by the liver is not directly related to blood pH reduction in this context. Bicarbonate ions act as a buffer in the blood to maintain pH, but the liver is not the primary regulator for the release of bicarbonate in response to pH.

Option 4: A decrease in pH does not directly reduce the rate of the heartbeat. However, extreme changes in blood pH (such as during severe acidosis) can affect the cardiovascular system.

Thus, decreased pH causes hemoglobin to release oxygen more readily to tissues, which is a key physiological response under certain conditions, like exercise or tissue inflammation.

The correct answer is:

Option 3: lacking clotting factors

Explanation:

Option 1: lacking globulins: This is incorrect. Serum still contains globulins. Serum is essentially blood plasma without the clotting factors (such as fibrinogen), but it still contains globulins, which include antibodies.

Option 2: lacking albumins: This is incorrect. Serum contains albumins, which are the most abundant proteins in plasma and are important for maintaining osmotic pressure.

Option 3: lacking clotting factors: This is correct. The key difference between serum and plasma is that serum lacks the clotting factors (like fibrinogen), which are used up during the process of blood clotting. Plasma, on the other hand, contains these clotting factors.

Option 4: lacking antibodies: This is incorrect. Serum contains antibodies, which are a type of globulin protein. These antibodies are important for immune responses.

Summary:

The main difference between serum and blood (plasma) is that serum lacks clotting factors, making Option 3 the correct answer.

The question asks why persons with the 'AB' blood group are called "universal recipients." Understanding the concept of blood grouping and antibodies is essential to answering this.

Blood group classification is based on the presence or absence of antigens and antibodies:

• Antigens are present on the surface of red blood cells (RBCs).
• Antibodies are present in the plasma.

Different blood groups are categorized as follows:

Individuals with the 'AB' blood group can receive blood from any other blood group due to the absence of anti-A and anti-B antibodies in their plasma. This lack of antibodies means their immune system does not attack foreign A or B antigens introduced through transfusion from other blood groups.

Explanation of Options:

• Absence of antigens A and B on the surface of RBCs: This is incorrect for the AB group because both A and B antigens are present.
• Absence of antigens A and B in plasma: Antigens are not present in plasma, hence irrelevant to the compatibility for transfusion.
• Presence of antibodies, anti-A and anti-B, on RBCs: RBCs do not have antibodies; they carry antigens.
• Absence of antibodies, anti-A and anti-B, in plasma: This is correct. The absence of these antibodies allows AB individuals to accept blood from any donor type without risk of an immune response against A or B antigens.

Thus, the correct answer is: Absence of antibodies, anti-A and anti-B, in plasma.

• Father's blood group : Possible genotypes are or .
• Mother's blood group : Possible genotypes are or .
• Child's blood group : Genotype must be , as blood group requires two recessive alleles.

• Option A:
  • Father:
  • Mother:
  • Child:
  • This combination is possible, as both and can produce an offspring.
• Option B:
  • Father:
  • Mother:
  • Child:
  • This option is not possible. Two homozygous dominant parents ( and ) cannot have an child.
• Option C:
  • Incompatible genotypes and results. Skipping explanation as it doesn't relate meaningfully to provided parent-offspring relationship.
• Option D:
  • Incompatible genotypes since no for child.
• Option E:
  • Incompatible genotypes as child cannot be .