Question

1.a)

Suppose that a genetic alteration resulted in the synthesis of cyclin-dependent kinases that no longer provided the "go" signal at the cellular checkpoint. Predict the immediate outcome if this were to alter the normal cell life-cycle processes at the G₂ checkpoint. The cells involved would

A. grow and otherwise function undergoing mitosis

B. exit the cell cycle completely and enter a nondividing cellular state

C. most likely remain in suspended metaphase, unable to enter anaphase

D. proceed as normal, enter the G₁, S, G₂, and M phases and divide

b)

Damage to the thalamus would not interrupt

A. information traveling to the occipital lobe about light detection

B. signals being integrated in the temporal lobe that indicate the intensity of noise

C. signals traveling to the cerebral cortex about pressure being applied to the skin

D. signals coming into the central nervous system meant to initiate a reflexive motion

c) A group of scientists determine that a single gene is responsible for controlling the height of a plant species. The height of the plants may be tall, medium, or short. The scientists perform several crosses of the plants. The results are shown in the table below:

Number of tall Number of medium Number of short offspring offspring offspring Tall x Tall 550 0 0 Total number of offspring 550 Tall x Medium 261 267 0 528 Tall x Short 0 492 0 492 Medium x Medium 132 277 135 544 Medium x Short 0 263 257 520 Short x Short 0 0 507 507

Based on the data in the table, which pattern of inheritance most likely determines height in this plant species?

A. codominance

B. complete dominance

C. incomplete dominance

D. multiple alleles

Answer 1

1. a) otion A is correct.

cells having altererd G2 (G/M) checkpoints enter into mitosis but after cytokinesis leading to death because these cells enter mitosis without DNA repairing.

b) option D is correct. Damage to the thalamus would not interrupt signals coming into the central nervous system meant to initiate a reflexive motion.

c) option A is correct i.e., codominance