Biology: From Stimulus to Reaction

Flashcards reviewing the biological concepts of stimuli, receptors, conductors, effectors, and reactions from the 'Van Prikkel tot Reactie' topic.

What is the correct sequential order of components in the biological pathway from a stimulus to a reaction?

The pathway is: Stimulus -> Receptor -> Conductor -> Effector -> Reaction.

What is the definition of a stimulus (prikkel)?

A stimulus is an observable change in an organism or in its environment that is capable of triggering a reaction.

What is meant by the stimulus threshold (prikkeldrempel)?

The stimulus threshold is the minimum strength a stimulus must have to be perceptible and trigger an impulse.

What occurs during stimulus habituation (prikkelgewenning)?

During stimulus habituation, an organism ceases to perceive a continuous environmental change after the same stimulus persists over a period of time.

What is the function of the stimulus filter (prikkelfilter)?

The stimulus filter acts as a processing station that determines whether and how strongly electrical signals (impulses) are transmitted to the brain via neural pathways.

How do chemical stimuli differ from physical stimuli?

Chemical stimuli consist of chemical molecules (such as smell, taste, and hormones), whereas physical stimuli consist of energy (such as light, sound, temperature) or force (such as pressure, touch, gravity).

What distinguishes external stimuli from internal stimuli?

External stimuli originate outside the body from the environment, while internal stimuli originate inside the body.

What primary function do receptors perform in an organism?

Receptors recognize and capture stimuli, allowing the organism to gather information about its internal or external environment.

Which specific receptor types detect temperature, light, and chemical molecules respectively?

Thermoreceptors detect temperature, photoreceptors detect light, and chemoreceptors detect chemical molecules (taste, smell, and acidity).

In which organisms are electroreceptors and magnetoreceptors found?

Electroreceptors are found only in fish (detecting electric currents), whereas magnetoreceptors are found only in sharks, bees, birds, and eels (detecting magnetic fields).

What specific stimuli are perceived by mechanoreceptors?

Mechanoreceptors detect mechanical forces including sound, blood pressure, proprioception (body position in space), balance, vibrations, and gravity (in plants).

What is a conductor, and what two systems serve as conductors in animals?

A conductor transmits information from a receptor to an effector. In animals, the nervous system (using impulses) and the hormonal/endocrine system (using hormones) function as conductors.

How do the nervous system and hormonal system differ as conductors in terms of regulation?

The nervous system controls both internal and external responses to regulate muscles and glands, whereas the hormonal system always provides internal regulation via hormones.

What serves as the conductor in plant organisms?

Hormones serve as the conductors in plants.

What is an effector, and what are the two main effectors in animals?

An effector carries out the reaction to a stimulus. In animals, the primary effectors are muscles and glands.

What structures act as effectors in plants, and what responses do they produce?

Plant cells act as effectors in plants, producing movements (tropism or nastic movement) or gland actions.

How do voluntary muscles differ from involuntary muscles in animals?

Voluntary muscles (e.g., skeletal muscles) are under conscious control and made of striated muscle tissue. Involuntary muscles (e.g., esophageal peristalsis, stomach contractions, pupil movement) act automatically and consist of smooth muscle tissue.

What type of muscle tissue composes the heart muscle?

The heart consists of cardiac muscle tissue (hartspierweefsel), which is striated muscle tissue operating involuntarily.

What three skin effectors react to cold temperatures, and what are their actions?

The effectors are sweat glands (sweating decreases), arrector pili muscles (contract, causing hair to stand upright), and blood vessel muscles (constrict to conserve heat).

How do the skin's sweat glands, arrector pili muscles, and blood vessel muscles respond to warm temperatures?

Sweat glands are stimulated to produce sweat, arrector pili muscles relax (allowing hairs to lie flat), and blood vessel muscles dilate blood vessels to release heat.