ENCYCLOPEDIA

SCIENCE

CONTENTS




  • Nourvous system
    • Neuron
    • Synapse
  • Respiratory Organs
    • Lungs
    • Alveoli
  • Human Eye
    • The Eye
    • Image ON Retina
  • Hman Heart
    • Human Heart
    • Functions Of Human Heart

NEURON



Neuron is a Nerve Cell that is the building block of the Nervous System.They receive and transmit electrochemical signals called nerve impulses to different parts of the body

SYNAPSE



A junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter.

LUNGS

Lungs are the primary organs of respiration in humans and other vertebrates. They are located on either side of the heart, in the thoracic cavity of the chest. Anatomically, the lungs are spongy organs with an estimates total surface area between 50 to 75 sq meters. The primary function of the lungs is to facilitate the exchange of gases between the blood and the air. Interestingly, the right lung is quite bigger and heavier than the left lung.
The alveoli are single-celled sacs of air with thin walls. It facilitates the exchange of oxygen and carbon dioxide molecules into or away from the bloodstream.

HUMAN EYE

"The face is the mirror of the mind, and eyes without speaking confess the secrets of the heart." – St. Jerome

IMAGE FORMATION

ON RETINA

  • Rays from the top and bottom of the object are traced and produce an inverted real image on the retina.
  • The retina contains photoreceptors (rods and cones) that convert light into an electric signal.
  • The brain translates these nerve impulses to form the final image.

HUMAN HEART

Your muscular heart, the main organ in your cardiovascular system, is vital for life. Its parts work together to move blood through your body in a coordinated way. It constantly sends oxygen to your cells and takes away waste. Many conditions can affect this organ and keep it from working well.
The human heart has several important function
  • Pumping oxygenated blood to other body parts.

  • Pumping hormones and other vital substances to different parts of the body.

  • Receiving deoxygenated blood and carrying metabolic waste products from the body and pumping it to the lungs for oxygenation.

  • Maintaining blood pressure