Animal Psychology exam 3

Ligands that bind to intracellular receptors are typically water-soluble.

False

Why might a pirate wear an eye patch over one eye when frequently moving between bright sunlight and the dark interior of a ship?

It keeps one eye dark-adapted so that photopigments (e.g., rhodopsin) remain in a functional state, allowing immediate vision in low light.

Cell signal transduction is the first messenger (ligand) binding to the second messenger (receptor).

False

Hair cells and photoreceptors both rely on the opening and closing of ion channels to generate depolarization or hyperpolarization in response to stimuli.

True

Cones and rods are ______ and ______ in the eyes.

Photoreceptors and telereceptors

Multiple graded potentials can combine to reach threshold in a neuron.

True

Which sensory receptor uses mechanically gated ion channels?

Hair cell

The resting membrane potential of neurons is usually around −70 mV.

True

Photopigments are located at:

Discs

Which of the following cannot be an efferent nerve?

Interneurons and sensory neurons

The nervous system includes the central nervous system and the peripheral nervous system. The peripheral nervous system includes the skeletal system and the autonomic nervous system.

False

Hair cells are epithelial cells.

True

After the photon is captured, the energy is utilized to activate opsin, a G-protein-coupled receptor to release ______.

G-protein subunits

Depolarization does not always lead to the generation of an action potential (AP). It must reach threshold; otherwise no AP.

True

Cell signaling pathways work independently; they never interact with each other.

False

In the procedure of phototransduction the energy of light (photon) is captured by ______.

Photopigments

Cones are responsible for color vision in humans.

True

Which ion movement is primarily responsible for the repolarization phase of an action potential?

K+ moving out of the cell

Photopigments are composed of ______.

Retinal and opsin

The major functions of glial cells in the nervous system are to conduct action potentials and connect the axons of neurons together.

False

Cell membrane facilitated diffusion requires ATP.

False

The membrane potential curve describes the voltage difference across the neuronal membrane.

True

In cell signal transduction, a receptor protein usually functions to synthesize proteins.

False

Which of the following statements about nociceptors or pain is correct?

Nociceptors are the bare nerve endings of sensory neurons that respond to intense stimuli

Find the cell signaling receptor location in the picture.

Target cell or effector cell

Cell signal transduction refers to the transfer of signals from the extracellular to the intracellular environment.

True

In cell signal transduction, the signals are ligands, which usually are nerve impulses.

False

At rest, the inside of the neuron is negatively charged relative to the outside.

True

Our eyes can distinguish colors because there are three types of cones in the retina that respond to different wavelengths of light corresponding to red, yellow, and blue.

False

Where are hair cells located? (Select all that apply)

Ampullae of the semicircular ducts; utricle and saccule; cochlear duct

Which statement is correct about cell function?

Neurons and muscle cells can respond to stimuli

Olfactory sensory neurons contain chemoreceptors that detect odorant molecules and initiate signal transduction.

True

Which description is right about neurons?

Sensory neurons are the afferent neurons

There are three auditory bones connecting the tympanic membrane and the oval window; the most important function of these bones is ______.

To amplify pressure (force per unit area) at the oval window

In the inner ear, the semicircular ducts are hollow, and air within the ducts deflects hair cells when the animal turns its head.

False

An action potential (red curve) begins when depolarization reaches threshold.

True

In phototransduction, light energy is converted into biochemical signals that regulate ion channels, causing changes in the membrane potential of photoreceptor cells.

True

Ion channels in the plasma membrane always require ATP to transport ions.

False

Cell membrane allows ______ to pass freely.

Fat soluble substances

Neurotransmitters are produced by neurons and released into ______.

Synaptic cleft

Inhibitory neurotransmitters usually make the membrane potential more negative.

True

Which structure receives neurotransmitters?

Ligand-gated Na+ channel on the postsynaptic membrane

The threshold potential in neurons refers to:

The membrane potential required to trigger an action potential

Which type of cell signaling receptor is located in the cytoplasm or the nucleus?

Intracellular receptor

The neuron voltage-gated sodium channels open during the depolarization phase of an action potential.

True

Which of the following molecules commonly acts as a ligand in cell signaling?

Insulin in blood circulation

Hair cells are ______ in the inner ear.

Mechanoreceptors

The membrane potential at rest is maintained by a voltage-gated Na+ channel.

False

Membrane depolarization is caused by Na+ channels pumping Na+ ions out of the membrane.

False