Control and Coordination Practice Flashcards

Comprehensive question-and-answer flashcards covering control and coordination in animals and plants, including human nervous system structures, reflex actions, brain anatomy, endocrine glands and hormones, and plant tropisms.

What is defined as any change in the environment that evokes a response in an organism?

Stimuli

Which sensory receptor in the skin is responsible for detecting heat and cold?

Thermo receptor

Which receptor in the skin is responsible for detecting pain?

Nociceptor

What type of receptors are located on the tongue and what do they detect?

Gustatory receptors, which detect taste.

Where are photoreceptors located and what stimulus do they detect?

Photoreceptors are located in the eyes and detect light.

What type of receptor is located in the nose and what stimulus does it detect?

Olfactory receptor, which detects smell.

What receptor in the ear is responsible for detecting sound?

Phono receptor

What are effectors in the nervous system and how do they act?

Effectors are muscle tissue and glands that act in response to stimuli.

What is the structural and fundamental unit of the nervous system?

Neuron (nerve cell)

Which cell is identified as the longest cell in the human body?

Neuron

What part of a neuron collects information in the form of a signal?

Dendrite

Along which part of the neuron does an electrical impulse or signal travel?

Axon (tail)

What is released at the nerve ending when an electrical signal arrives?

Chemicals (which are released due to a chemical reaction triggered by the electrical impulse)

What is a synapse?

A microscopic gap between two neurons.

What is a nerve?

A bundle of fibers that carries signals between the brain and other parts of the body, enabling sensation, movement, and other functions.

What components form the Central Nervous System (CNS)?

The brain and the spinal cord.

What are cranial nerves and spinal nerves?

Cranial nerves are nerves originating from the brain, while spinal nerves are nerves originating from the spinal cord.

What is the Neuromuscular Junction (NMJ)?

The point of touch between a motor neuron and an effector.

How do muscle cells alter their shape to cause movement in response to nervous electrical impulses?

Muscle cells contain specialized proteins that change their shape in response to nervous electrical impulses.

What neuron connects sensory neurons and motor neurons in a reflex arc?

Relay neuron (or Interneuron)

What is a reflex action?

A quick, sudden, and involuntary movement in response to a stimulus that is uncontrolled by will and does not involve thinking or brain involvement.

What is the evolutionary importance of the reflex arc in animals?

It allows an instant reaction via the spinal cord, bypasses the brain's complex processing, and reduces response/thinking time.

How do voluntary actions differ from involuntary actions regarding conscious control and thinking?

Voluntary actions are controlled by will, involve thinking, and involve the brain; involuntary actions are uncontrolled by will, do not involve thinking, but still involve the brain.

Give examples of voluntary actions and involuntary actions listed in the notes.

Voluntary actions include walking and talking; involuntary actions include blood pumping and digestion.

What specific functions are controlled by the Hypothalamus?

Hunger and thirst control.

Which part of the brain is the largest and serves as the primary thinking center?

Cerebrum (part of the Fore Brain)

What bundle of nerve fibers connects the left and right hemispheres of the brain?

Corpus callosum

What is the main function of the Mid Brain?

It connects the fore brain and hind brain, and works together with the hind brain to control involuntary actions.

Which three distinct structures make up the Hind Brain?

Pons, Cerebellum, and Medulla (PCM).

What are the primary functions of the Pons?

Regulating breathing rate and the sleep cycle.

What functions are controlled by the Cerebellum?

Precision of voluntary actions (e.g., holding a pencil), balance, and posture.

What involuntary actions are controlled by the Medulla?

Blood pressure (BP), salivation, heartbeat, and vomiting.

What three components provide protection to the brain?

Cranium (skull), meninges (3 thin membranes), and CSF (cerebrospinal fluid).

What structure provides physical protection for the spinal cord?

Vertebral column (backbone).

Which endocrine gland is referred to as the Master Gland?

Pituitary gland

What conditions result from a deficiency or an excess of growth hormone?

Deficiency causes dwarfism, while excess causes gigantism.

Which hormone is secreted by the thyroid gland, and what element is required for its production?

Thyroxine hormone, which requires iodine.

What biological processes are regulated by thyroxine hormone?

Carbohydrate, protein, and fat metabolism.

Where is the thyroid gland located in the body?

In the front of the neck, just below the larynx.

What is hypothyroidism and how can it be managed?

It is a medical condition where the thyroid gland does not produce enough thyroid hormone due to iodine deficiency (causing neck swelling), managed by taking iodized salt.

What hormone is secreted by the pancreas and what is its main function?

Insulin, which controls blood sugar levels.

What hormone is secreted by the adrenal gland in emergency situations, and what is its nickname?

Adrenaline, which is nicknamed the flight or fight or emergency hormone.

What physiological changes occur in the body when adrenaline is released?

Heartbeat increases, breathing rate increases, blood flow to skeletal muscles increases, and blood supply to the digestive system decreases.

What hormones are secreted by the male and female sex organs, respectively?

Testes in males secrete testosterone; ovaries in females secrete oestrogen.

What is the feedback mechanism in the endocrine system?

A mechanism where the timing and amount of hormone released are regulated based on body conditions (e.g., blood sugar levels increasing causes more insulin secretion).

In what form is food stored in animals?

Glycogen

What are two major limitations of electrical impulses in the nervous system?

1. Limited range (signals cannot reach every cell in the body). 2. Reset time (neurons need a period to reset before transmitting another signal).

Why is chemical communication via the endocrine system advantageous over electrical signaling?

Chemical signals reach all cells through the bloodstream (wider range) and produce slower, longer-lasting effects essential for growth and metabolism.

How is coordination achieved in plants despite the absence of a nervous system?

Stimuli are communicated through a combination of electrical and chemical signals traveling cell to cell.

What is the difference between positive tropism and negative tropism in plant growth movements?

Positive tropism is plant growth towards a stimulus (e.g., stem growing towards light), whereas negative tropism is plant growth away from a stimulus (e.g., roots growing away from light).