Catégories : Tous - signals - muscles - brain - neurons

par Enaya Alaa Il y a 8 années

336

organ systems

The nervous system plays a crucial role in transmitting information throughout the body via electrical signals. Composed of neurons encased in connective tissues and covered in fatty material to prevent miscommunication, it facilitates communication and coordination of bodily activities.

organ systems

made up of bundle of neurons surrounded by connective tissues

are covered by fatty material, prevents electric impulses from passing to wrong neurons

does not easily repair

sends information around the body by conducting electrical signals from one area to another

organ systems

circulatory system

blood

type of connective tissues that circulates throughout the body and consists of

platelets

they help the blood clotting

white blood cells

they recognize and destroy invading bacteria

make less than 1% of the blood's volume

plasma

protein-rich liquid that carries the blood cells along

red blood cells

make up half of the blood's volume

contains hemoglobin which makes it look red and allows them transport oxygen

blood vessels

capillaries

exchanges gases, wastes and nutrients between the blood and body tissues

veins

walls are not as thick because it takes blood to the heart, low pressure level

arteries

thick walls because it is pumped from the heart with high pressure

heart

pumps the blood to the blood vessels

connective tissues

nerve tissues

covered by a smooth layer of epithelial tissues from outer and inner surface of the heart

outer:  reduces damage caused by friction when the lungs expand

inner : to help the blood flow freely

cardiac muscle tissues

they all contract, at the same time in each part of the heart, moving the blood around

transports enzymes to the kidney
regulate body temperature and transport white-blood cells to disease areas
carry away wastes through the blood streams
move nutrients and gases to the cells

digestive system

the accesory organs

they help in the digestion process by supplying digestive enzymes

pancreas

produces insulin, which helps regulate the concentration of glucose in blood

liver

produces bile, which is delivered into the digestive tract, where it helps in digesting fats in food

the digestive tract

anus

its the end of the tract. From there, the remaining solid matter is secreted as feces

intestine

its the part of the digestive tract that's between stomach and anus

contains smooth muscles

has many blood vessels

its liningcells, goblet cells, produces mucus

its parts

large intestine

its lining absorbs water from indigestible food

1.5 m long and larger in diameter than small intestine

small intestine

most digestion occurs

then nutrients diffuse through its wall to the blood stream to be delivered to the cells

6 m long and narrow

stomach

it holds food and churns it by

nerves that signal when we have enough food

smooth muscle tissues that contract to mix the contents

enzymes produced by tissues lining it

esophagus

it's made up of smooth muscle tissues, which are controlled by nerve tissues

contract and relax to move food down to the stomach

food is then swallowed to it, it connects the mouth to your stomach

mouth

starts the process of breaking food

chemically

with enzymes (saliva ) that break down the particles of food, which are made by epithelial tissues lining the mouth

mechanically

with the teeth and tongue

is the organ system that takes food in, digests it and gets rid of the remaining wastes

nervous system

nerves

made up of neurons, it sends information around the body by conducting electrical signals from one area to another

peripheral nervous system

are ended by sensory reseptors

it receives input from environment and sends it through the nerves to the brain.

nerves that carry signals between the central one and the rest of the body

nerves that control the voluntary muscles

nerves that carry information from the sensory organs to the brain

nerves that control the involuntary function

central nervous system

its supported by bones to protect it

spinal cord

protected by the spine

brain

protected by the skull

surrounded by fluids, it helps protect from injury, transport chemicals and removes wastes produced

communication and coordination of the body activities


senses the environment and carries messages of the appropriate response

musculoskeletal system

made up of
skeleton

cartilage

provides a strong, flexible and low-friction support for bones

dense connective tissues, made of special cells

ligaents

are tough and elastic, hold bones together

bones

are hard and dense, have canals inside them that contain nerves and blood vessels

muscles

movement

the two ends of the muscle are attached into two different bones by tendons

when muscles contract they exert a force and pull on or both the bones its attached to

they work in opposite pairs, muscles can pull but not push

are consisted of many long cells called muscle fibers that contain specialized proteins

these proteins cause muscles contract when signaled by the nerves from the brain

when it contracts, it becomes shorter and thicker

skeletal (involuntary)

smooth (voluntary)

supports the body, protects delicate organs, and moves the body

respiratory sytem

function in the body
exchanges gases between the body and the environment, oxygen into the body and carbon dioxide out of it in the process of diffusion

gas exchange

its the process of gases exchange between the alveoli and the blood stream

after the air is in the alveoli it has to be delivered to all body parts, it has to go to the circulatory system by entering the blood stream

the alveoli has thin walls, so gases diffuse only through to thin walls, alveoli and blood vessel

breathing

you can control your breathing but for a short period of time, soon the involuntary system takes over again

it is controlled by parts of the brain that send signals if the carbon dioxide concentration is high in the blood to the diaphragm

the breathing rate increases an heart beats faster which decreases the CO2 in the blood

muscles between the ribs, that move it, and the diaphragm change the lungs volume which changes pressure inside the lung and allows fresh air into and out the alveoli

inhaling

volume increases

muscles contract

diaphragm flattens

air into the lungs

exhaling

volume decreases

muscles relax

diaphragm dome-shaped

air out of the lungs

parts
lungs

its the muscle that has the alveoli, its increasing and decreasing volume changes the pressure inside them, in this way fresh air flows into ad out the alveoli

alveoli

tiny sacs of air in the lungs that are surrounded by capillaries, gas exchange happens there

bronchi

its the part of the trachea when it splits into to parts

trachea

air goes down it, it is supported by rings of cartilage, special type of connective tissues, that keeps it open and allows the air to flow

pharynx

air passes through it

mouth and nose

the air enters through them