IGCSE Biology: Co-ordination & Response

These flashcards cover essential vocabulary related to the topics of co-ordination and response in IGCSE Biology, focusing on homeostasis, nervous and hormonal control, and plant responses.

Homeostasis

The control or regulation of the internal conditions of a cell or organism.

Stimulus

A change in the environment that causes a response.

Receptor

Cells or structures that detect stimuli.

Effector

A muscle or gland that brings about a response to restore optimum levels.

Phototropism

A plant's growth response towards or away from light.

Geotropism

A plant's growth response towards or away from gravity.

Auxin

A plant hormone that controls directional growth responses and cell elongation.

Neurone

A nerve cell that transmits electrical impulses through the nervous system.

Synapse

The junction between two neurones where neurotransmitters cross.

Neurotransmitter

Chemicals that transmit signals across the synapse from one neurone to another.

Reflex Arc

The pathway taken by electrical impulses during a reflex response.

ADH (Antidiuretic Hormone)

A hormone that helps control the water content of the blood by increasing kidney reabsorption.

Insulin

A hormone produced by the pancreas that lowers blood glucose levels by facilitating glucose uptake.

Ciliary Muscles

Muscles that control the shape of the lens in the eye for focusing.

Vasodilation

The process by which blood vessels widen to increase blood flow and heat loss.

Vasoconstriction

The process by which blood vessels narrow to reduce blood flow and heat loss.

Pupil Reflex

A reflex action that regulates the size of the pupil in response to light intensity.

Gland

A group of cells that produces and releases one or more substances (secretion).

Hormone

A chemical substance produced by a gland that alters the activity of target organs.