Homeostasis notes #1 (copy)

Homeostasis

The maintenance of a relatively constant internal state, regardless of external changes.

Negative Feedback System

A process that counteracts a detected change to restore the body's set point.

Thermoreceptors

Sensitive receptors that detect temperature changes in the skin and hypothalamus.

Vasodilation

The dilation of blood vessels to release heat through increased blood flow to the skin's surface.

Vasoconstriction

The constriction of blood vessels to conserve heat by reducing blood flow to the skin's surface.

Action potential

A rapid change in electric potential of the cell membrane that allows for signal transmission.

Synapse

The gap between neurons where impulses are transferred via neurotransmitters.

Endocrine System

The system that regulates body activity via hormones, which have slower but longer-lasting effects.

Adaptations in Endotherms

Mechanisms that allow endotherms to maintain body temperature within a narrow range, independent of external temperatures.

Behavioural Adaptations

Actions taken by organisms to regulate their temperature, such as seeking shade or changing body position.

Structural Adaptations

Physical features that aid in temperature regulation, such as insulation provided by fur or blubber.

Physiological Adaptations

Internal processes that adjust metabolic activity to maintain body temperature.

Osmoreceptors

Receptors that detect osmotic pressure changes, important for maintaining fluid balance.

Chemoreceptors

Receptors that detect chemical concentrations, such as blood glucose or oxygen levels.

Neuron

A nerve cell that transmits impulses, consisting of a cell body, dendrites, and an axon.

CNS (Central Nervous System)

The part of the nervous system comprised of the brain and spinal cord.

PNS (Peripheral Nervous System)

Nerves that connect the CNS to limbs and organs throughout the body.

Hypothalamus

A critical control center that links the nervous and endocrine systems to maintain homeostasis.

Neurotransmitters

Chemicals that transfer signals across the synapse from one neuron to another.

Pituitary Gland

A gland that regulates other glands and hormones within the endocrine system.

Receptors

Sensors that detect internal or external stimuli to trigger homeostatic responses.

Tolerance Limits

The narrow range within which variables like body temperature and pH are maintained.

Myelin

A fatty substance that insulates axons, speeding up signal transmission.

Islets of Langerhans

Clusters of cells in the pancreas responsible for regulating blood glucose levels.