BioNinja Notes - Equilibrium

Emergent properties

New synergistic effects created from the collective actions of different structures in a biological system.

Communication networks

Mechanisms that allow multicellular organisms to function by integrating individual cell functions.

Nervous system

A rapid communication system involving electrochemical impulses.

Endocrine system

A wired distributed system that uses chemical messengers for prolonged effects.

Neurons

Specialized cells that transmit electrochemical signals within the nervous system.

Central nervous system (CNS)

The part of the nervous system including the brain and spinal cord responsible for processing information.

Peripheral nervous system (PNS)

The part of the nervous system made up of sensory and motor neurons transmitting information to/from the CNS.

Myelin sheath

A layer of fatty tissue that insulates nerve cells and improves transmission speeds.

Stimulus-response model

Basic pathway for a nerve impulse involving detection, processing, and response to a stimulus.

Reflex arc

A simple signaling pathway that allows for a rapid and involuntary response to stimuli.

Cerebral hemispheres

Two halves of the brain responsible for higher-order cognitive functions.

Gyrification

The folding of the cerebral hemispheres to increase cognitive capacity.

Frontal lobe

Part of the cerebrum involved in voluntary motor activities and speech production.

Parietal lobe

Part of the cerebrum responsible for sensory perceptions like touch, smell, and taste.

Occipital lobe

The visual processing center of the brain, used for sight perception.

Temporal lobe

Part of the cerebrum involved in auditory processing and language comprehension.

Corpus callosum

A bundle of myelinated nerve fibers that enables communication between the two cerebral hemispheres.

Cerebellum

Part of the brain responsible for coordination of complex motor actions, balance, and proprioception.

Brainstem

Connects the cerebrum to the spinal cord and controls involuntary functions such as breathing and heart rate.

Hypothalamus

Region of the brain that acts as a homeostatic control center and regulates hormonal secretion.

Pituitary gland

Master gland of the endocrine system that releases hormones regulating other glands.

Endocrine glands

Glands that secrete hormones directly into the bloodstream.

Homeostasis

The maintenance of a stable internal environment within physiological limits.

Negative feedback

A process whereby physiological responses negate changes to restore equilibrium.

Diabetes mellitus

A metabolic disorder characterized by the inability to regulate blood glucose concentrations.

Type I diabetes

An autoimmune disease resulting in the destruction of insulin-producing beta cells.

Type II diabetes

A condition where the body becomes resistant to insulin.

Thermoregulation

The process by which homeotherms maintain a stable body temperature.

Circadian rhythms

Physiological responses that follow a 24-hour cycle, regulated by melatonin.

Cardiac output

The volume of blood the heart pumps per minute, controlled by the medulla oblongata.

Chemoreceptors

Sensory receptors that detect changes in chemical concentrations in the blood.

Enteric nervous system (ENS)

A part of the nervous system that controls the gastrointestinal system.

Vasodilation

The widening of blood vessels to increase blood flow and heat loss.

Vasoconstriction

The narrowing of blood vessels to reduce blood flow and conserve heat.

Adrenaline

A hormone released during stress, enhancing 'fight or flight' responses.

Thyroxin

A hormone produced by the thyroid gland that regulates metabolism.

Melatonin

A hormone regulating sleep-wake cycles and circadian rhythms.

Hormones

Chemical messengers released by endocrine glands into the bloodstream.

Pancreas

An organ that produces insulin and glucagon to regulate blood sugar levels.

Ovaries

Female reproductive glands that synthesize sex hormones like estrogen.

Testes

Male reproductive glands that produce the male sex hormone testosterone.

Feedback loops

Systems that maintain homeostasis by regulating physiological changes.

Neuroendocrine glands

Glands that link the nervous and endocrine systems to maintain homeostasis.

Receptors

Specialized proteins that detect specific stimuli and initiate physiological responses.

Cognitive functions

Higher order processes such as learning, memory, and critical thought.

Pain receptor

Sensory neuron that detects painful stimuli.

Afferent nerves

Nerves that send signals to the CNS from sensory organs.

Efferent nerves

Nerves that carry signals from the CNS to effectors like muscles and glands.

Electrical impulses

Rapid signals transmitted along neurons in the nervous system.

Chemical messengers

Substances like hormones that carry signals through the bloodstream.

Internal equilibrium

Stability in physiological conditions necessary for survival.

Corticosteroids

Hormones synthesized in the adrenal glands that help regulate metabolism and immune response.

Eicosanoids

Locally acting signaling molecules derived from fatty acids.

Neuropeptides

Small protein-like molecules used by neurons to communicate.

Ion channels

Membrane proteins that allow ions to enter or exit cells, crucial for nerve signaling.

Synapse

The junction between two neurons where communication occurs.

Action potential

A rapid rise and fall in voltage across a cellular membrane, crucial for nerve impulse transmission.

Neurotransmitters

Chemicals released at a synapse to transmit signals between neurons.

Ganglia

Clusters of nerve cell bodies in the PNS that process information.

Meninges

Protective membranes covering the brain and spinal cord.

Cerebrospinal fluid

Fluid that cushions and protects the brain and spinal cord.

Dopamine

A neurotransmitter involved in reward and pleasure centers in the brain.

Serotonin

A neurotransmitter that contributes to feelings of well-being and happiness.

Homeostatic regulation

Adjustments to maintain internal stability in response to environmental changes.

Physiological variations

Changes in physiological states that must be monitored for homeostasis.

Blood pH levels

The acidity or alkalinity of blood measured in terms of [H+] concentration.

Circadian disruptions

Variations in sleep-wake cycles often leading to health issues.

Insulin

A hormone that lowers blood sugar levels by promoting glucose uptake.

Glucagon

A hormone that raises blood sugar levels by promoting glucose release.

B cells

Insulin-producing cells found in the pancreas.

A cells

Glucagon-producing cells found in the pancreas.

Metabolic reactions

Biochemical processes essential for maintaining life.

Physiological responses

Actions taken by the body in response to changes in internal or external conditions.

Glycogen

A storage form of glucose found in the liver and muscles.

Respiratory gases

Gases exchanged in the lungs, primarily oxygen and carbon dioxide.

Peristalsis

Involuntary contractions that move food through the digestive tract.

Adaptation

The process of changing in response to environmental changes.

Voluntary control

Conscious control over certain physiological actions, such as movement.

Involuntary control

Unconscious regulation of physiological processes, like heartbeat.

Fatigue

A state of physical or mental exhaustion resulting from exertion.

ATP

Adenosine triphosphate, the primary energy carrier in cells.

Vascular system

The system responsible for transporting blood and nutrients throughout the body.

Thermoreceptors

Sensory receptors that detect changes in temperature.