11) The cell membrane is relatively impermeable to a) Polar molecules&ions; b) N

Question

11) The cell membrane is relatively impermeable to a) Polar molecules&ions; b) Non-polar molecules&cations; c) Lipid soluble substances d) Neutral chemicals e) High molecular weight biomolecules 12) In Living cells the weakest bond of two or more atoms is: a) lonic bond b) Covalent bond c) Sulfa hydric bond d) .Hydrogen bond e) None 13) The disease sickle cell anemia is a good example of what may happen a) When there is not enough iron in the diet b) When there is not sufficient heme in the hemoglobin c) Ared blood cell doesn't bind enough oxygen d) RBC's clump cause hemolysis e) When an amino acid residue is altered in the protein molecule 14) The sickle disease is: a) Sex-linked genetic disorder b) Dominant trait c) Recessive trait d) Do-dominant e) None of the above 15) Recessive X-linked traits are: a) Passed from fathers to their sons b) More likely to be expressed in males c)Always express in females Not be able t0 pass from mothers to their daughters

Explanation / Answer

12. In living system weakest bond is ionic bond. Gives 3-7 kcal/mole energy.

13. In sickle cell anemia a point mutation occurs in 6th position of beta chain and converts glutamic acid(GAG) to valine (GUG). As valine is hydrophobic It decrease elasticity resulting improper folding of haemoglobin. Hb no more bind with oxygen as before so RBC looks like sickle shaped (e).

14. The sickle disease is autosomal and recessive disease (c).

15. Recessive X linked traits are more likely to express in males. As males have only one x chromosome so chances of being carrier is 0. Mutation in one x chromosome leads to expression of disease.

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.