Co-ordination and Response

Co-ordination and Response

Coordination and Response

  • Coordination refers to how our bodies link the information from different parts of the body and respond accordingly.
  • The nervous system and the endocrine system are the primary systems responsible for this.
  • Coordination in the body helps to maintain stability in varying environments, a concept known as homeostasis.

The Nervous System

  • Involves detecting changes in the environment (stimuli) and responding to them.
  • Consists of the central nervous system (the brain and spinal cord) and the peripheral nervous system (nerves connecting the central nervous system to the entire body).
  • When a stimulus is detected, nerves carry electrical signals, or nerve impulses, to and from the brain and spinal cord.

The Endocrine System

  • Comprises glands that secrete hormones into the blood; hormones travel to specific target cells in the body.
  • Endocrine glands include the pituitary, thyroid, adrenal glands, ovaries in women and testes in men.
  • Hormones regulate body functions like metabolism, growth, and reproduction.
  • An example is insulin, a hormone produced by the pancreas that controls blood glucose levels.

Homeostasis

  • The body needs to maintain a stable internal environment, despite changes in the external environment; this is homeostasis.
  • Examples of homeostasis include regulation of body temperature, water balance, and blood sugar levels.
  • Both the nervous and endocrine systems play crucial roles in homeostasis by detecting changes and triggering responses.

Nervous Responses and Reflex Arcs

  • A reflex is a rapid, automatic response to a stimulus.
  • Reflexes often involve a simple nerve pathway called a reflex arc, bypassing the brain to protect from harm.
  • Reflex actions ensure immediate response to potentially harmful stimuli, like touching something hot.
  • In a reflex arc, the pathway involves sensory, relay, and motor neurons.

Plant Responses to Stimuli

  • Plants respond to stimuli too, a process known as tropism.
  • Two main types of tropism are phototropism (response to light direction) and geotropism or gravitropism (response to gravity).
  • Phototropism causes shoots to grow towards the light and roots to grow away from it.
  • Gravitropism ensures roots grow downwards into the soil and shoots grow upwards against gravity.