BIO225+Practice+Exam+2_W25_KEY

Transduction

The process of converting incoming sensory stimuli into changes in membrane potential.

Receptor Potential

The change in membrane potential in a sensory receptor cell.

Polymodal Receptors

Sensory receptors that respond to more than one class of stimulus.

Dynamic Range

The range of stimuli intensities to which a receptor can respond.

Stereocilia

Hair-like structures in hair cells that detect mechanical changes.

Hyperpolarization

An increase in membrane potential difference, making the inside of the cell more negative.

Photoreceptor

A cell that captures light energy and converts it to electrical signals.

Ionic Channels

Proteins that allow ions to move across membranes, important in transducing signals.

Ciliary Photoreceptors

Photoreceptors that utilize a different mechanism for responding to light as compared to rhabdomeric photoreceptors.

Hormone Action

The specific effect a hormone has on target cells based on receptor binding.

Negative Feedback Loop

A process in which a system responds in a way that reduces the effect of the input signal.

G Protein-Coupled Receptors

A large family of receptors that sense molecules outside the cell and activate internal signal transduction pathways.

Thyroid-Releasing Hormone (TRH)

A hormone released from the hypothalamus that stimulates the release of thyroid-stimulating hormone (TSH).

Endocrine Regulation

Control of physiological functions through hormones released into the bloodstream.

Acromegaly

A disorder caused by excessive growth hormone, leading to enlarged bones and tissues.

Glycogenesis

The metabolic pathway in which glucose is converted to glycogen for storage.

Fovea Centralis

The part of the retina where visual acuity is highest due to a high concentration of cone photoreceptors.

Ligand-Gated Ion Channels

Ion channels that open in response to the binding of a ligand.

Anatomic Targeting

The direct delivery of hormones to specific tissues based on their proximity.

Photoreceptors

Cells sensitive to light, including rods and cones in the retina.

Corticotropin-Releasing Hormone (CRH)

A hormone that stimulates the anterior pituitary to release ACTH.

Oxytocin

A hormone that plays a key role in childbirth and lactation.

Insulin-like Growth Factor-I (IGF-I)

A hormone that plays an important role in growth and development.

Spermatogenesis

The process of sperm cell development.

Oogenesis

The process of egg cell development.

Homeostasis

The maintenance of stable internal physiological conditions.

Cyclic AMP (cAMP)

A secondary messenger involved in signal transduction pathways.

Steroid Hormones

Hormones that are lipophilic and can pass through cell membranes to bind to intracellular receptors.

Hormone Clearance

The process by which hormones are removed from circulation.

Receptor Dimerization

The process where two receptor molecules bind together, often in response to a ligand.

Neurohormones

Hormones released from neurons into the blood circulation.

Signal Transduction Pathways

Methods by which a cell responds to molecules outside of it and converts the signal into a functional response.

Mammalian Eye

The complex structure that includes various components involved in vision.

G-protein linked receptors

A type of receptor that transmits signals through the activation of G-proteins.

Endocrine Organs

Glands that secrete hormones into the bloodstream.

Prohormones

Inactive precursors to hormones that require cleavage to become active.

Insulin Receptors

Cell surface receptors that bind insulin and help regulate glucose uptake.

Adenylate Cyclase

An enzyme that converts ATP to cAMP upon stimulation by G protein-coupled receptors.

Mechanoreceptors

Sensory receptors that respond to mechanical pressure or distortion.

Chemoreceptors

Sensory receptors that respond to chemical stimuli.

Phototransduction

The process by which light is converted into electrical signals in the retina.

Neural Signal

An electrochemical signal transmitted by neurons.

Target Tissue

Specific tissues that respond to the hormone due to the presence of specific receptors.

Positive Feedback Mechanism

A process where the output enhances the input signal.

Ciliary Body

Part of the eye that controls the shape of the lens.

Posterior Pituitary

The part of the pituitary gland that releases hormones, including ADH and oxytocin, produced in the hypothalamus.

Gonadotropins

Hormones that stimulate the gonads, such as FSH and LH.

Pituitary Gland

An endocrine gland that controls various hormonal functions in the body.

Nuclear Hormone Receptors

Intracellular receptors that directly influence gene expression upon binding with their respective hormones.

Diabetes Mellitus Type 1

A chronic condition in which the pancreas produces little or no insulin due to autoimmune destruction of beta cells.