Biology 30 Live Homework Help Board

Tactile acuity refers to the minimum separation required between two points for the brain to perceive them as two separate points.

When comparing the tactile acuity of various body parts, what have you concluded about the number of receptors in the palm of your hand relative to the number of receptors on your shoulder?

Select one:

. The tactile acuity for the palm is larger than for the shoulders. Therefore, more receptors are found on the shoulders than on the palm.

The tactile acuity for the shoulders is larger than for the palm. Therefore, more receptors are found on the palm than on the shoulders.

The tactile acuity for the shoulders is larger than for the palm. Therefore, more receptors are found on the shoulders than on the palm.

. The tactile acuity for the palm is larger than for the shoulders. Therefore, more receptors are found on the palm than on the shoulders.

Posted 5 years ago by miyaomar in Biology 30 | 2 answers
#receptors

Potassium channels opens, allowing potassium ions to move out. Some sodium channels open in the dendrite. All ion channels close and the Na+/K+ exchange pump starts working. Sodium ions diffuse toward the first node of Ranvier in the axon Lights hit the retina. The threshold level is reached at the first node of Ranvier in the axon Sodium channels open in the neural membrane of the axon, allowing the remaining sodium ions to move in.

Posted 5 years ago by miyaaa in Biology 30 | 0 answers
#eye

Which of the following statements about the intensity of a nerve response is true?

Select one:

. All stimuli, regardless of the strength, will always generate a nerve impulse.

. A small voltage shift and a large voltage shift will yield the same nerve impulse as long as the stimulus reaches the threshold level.

. A stimulus resulting in a greater voltage shift will result in a stronger nerve impulse and increased sense of perception in the brain.

A stimulus reaching the threshold level may or may not propagate a nerve impulse.

Posted 5 years ago by miyaomar in Biology 30 | 2 answers
#action potential #tactileacuity #eye

Neurotransmitters are released into the synaptic cleft. Neurotransmitters bind to ion channels. Sodium ions enter into the dendrites. Neurotransmitters are returned to the axon terminal, broken down by the enzymes or diffused away from the synapse. Action potential arrives in axon terminal. Synaptic vesicles containing the neurotransmitters fuse with the presynaptic membrane. Ion channels open.

The sequence in which the events numbered above are involved in the signal transmission across the synapse is

Posted 5 years ago by miyaomar in Biology 30 | 1 answers
#action potential #receptors #sensory pathway

Which of the following choices correctly describes the sensory pathway?

Sensory neuron → brain → motor neuron

Sensory receptors → sensory pathway → parietal lobe → motor pathway → muscles

Sensory neuron → spinal cord → motor neuron

. Sensory receptors → sensory pathway → spinal cord → motor pathway → muscles

Posted 5 years ago by miyaomar in Biology 30 | 1 answers
#sensory pathway #reflex arc #and sensory pathways #membrane

Which of the following toxins can counteract the activity of diisopropyl fluorophosphate by preventing the binding of acetylcholine to the protein receptor?

Select one:

Female black widow spider venom

. Botulinum toxin

Reserpine

Curare

Posted 5 years ago by miyaomar in Biology 30 | 1 answers
#insects #receptors

Select the statements that correctly describe positive feedback pathways.

A sensor/receptor is required to monitor and limit levels. A sensor/receptor is unnecessary to monitor and limit levels. Feedback prevents homeostasis. Feedback contributes to homeostasis. Feedback stimulates the effector to continue to do the same thing. Feedback stops the effector from doing one thing and stimulates it to do the opposite. When the target level for a hormone is reached, feedback results in a reduction of that hormone being released. When a target level for a hormone is reached, feedback results in an increase of that hormone being released.

Posted 5 years ago by miyaomar in Biology 30 | 2 answers
#positive feedback #sensory pathway #receptors

ADH is produced by the hypothalamus and stored in the posterior pituitary. It increases the reabsorption of water by the kidneys. ADH secretion is suppressed by diuretics such as alcohol and caffeine. Which of the following would be exhibited in someone after excessive alcohol intake?

Select one:

. Decreased urination