Question

12. A plant has a dominant phenotype but an unknown genotype. The proper experiment to determine its correct genotype would be a/an: a. heterozygotic cross. b. testcross. c. homozytic cross. d. F1 cross. e. back cross. 13. The correct model of the structure of a DNA molecule was first elucidated/proposed by: a. Franklin and Wilkins. b. Linus Pauling. c. Hershey and Chase. d. Erwin Chargaff. e. Watson and Crick. 14. Steroid hormones (like testosterone) are somewhat unusual in that their receptors are: a. located on the outside of the plasma membrane. b. not involved in signaling pathways. c. intracellular and commonly found in the cytoplasm. d. hydrophobic and located inside the plasma membrane. e. located in the nuclear membrane. 15. Quorum sensing is a process associated with: a. the fight or flight response. b. yeast mating. c. muscle contraction in mammals. d. cAMP-associated responses by a range of higher eukaryotic cells. e. certain

Answer 1

the correct answers are as follows

12:

b. Testcross- an organism with dominant phenotype but unknown genotype is crossed with homozygous recessive organism for the same trait. Based on the results obtained, if all offsprings have the same phenotype, then the parent is homozygous, but when a 1:1 ratio is observed in the offsprings, then the parent is heterozygous.

13.

e. Watson and Crick- they both used the crystallographic images from Franklin, analyzed them to first elucidate the 3D structure of the DNA and propose it to the world.

14.

c. Intracellular and commonly found in the cytoplasm- the receptors of steroid hormones are generally present within the target cell either in the cytoplasm or nucleus, since they alter gene expression.

15

e. Certain prokaryotes/bacteria- this is a process that will enable disease-causing pathogens to communicate and cooperate with their group, by the release of autoinducers that increase their cell density.