Describe the phototransduction process
What will be an ideal response?
When a photopigment molecule absorbs light it dissociates into its retinene and opsin components. This light-induced breakdown and subsequent activation of the photopigment bring about a hyperpolarizing receptor potential that influences transmitter release from synaptic terminal of the photoreceptor. The light-induced biochemical change in the photopigment leads to closing of chemical messenger-gated sodium channels in the outer segment's membrane. This hyperpolarization, which is the receptor potential, passively spreads from the outer segment to the synaptic terminal of the photoreceptor. The photoreceptors synapse with bipolar cells.?These cells terminate on the ganglion cells, whose axons form the optic nerve for transmission of signals to the brain. The transmitter released from the photoreceptors synaptic terminal has an inhibitory action on the bipolar cells. The reduction in transmitter release that accompanies light-induced receptor hyperpolarization decreases this inhibitory action on the bipolar cells.
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A. secreting renin B. contributing to calcium homeostasis C. secreting erythropoietin D. deaminating amino acids E. producing uric acid
LH is also referred to as a gonadotropin
Indicate whether the statement is true or false
A urine test reveals a positive result for human chorionic gonadotropin (hCG). This indicates ________ was successful
A) gastrulation B) fertilization C) ovulation D) implantation
Which joint is a synchondrosis?
A) Sternocostal B) Interphalangeal C) Intertarsal D) Intervertebral