Download Cells Working Together Transcript

Description:
Cells Working Together: Tissues and Organs
MULTICELLULAR ORGANISMS CAN HAVE HUNDREDS
OF DIFFERENT TYPES OF SPECIALIZED CELLS,
AND YET, IT IS QUITE RARE TO FIND CELLS
THAT CARRY OUT THEIR TASKS ALONE.
THAT IS BECAUSE, IN COMPLEX ORGANISMS,
CELLS ARE ALMOST ALWAYS FOUND WORKING TOGETHER
IN ORGANIZED GROUPS.
FOR EXAMPLE...
...ARE CALLED "TISSUES."
HERE WE SEE A TISSUE OF CELLS
THAT MAKES UP THE OUTER LAYER OF A LEAF.
VERY OFTEN, SEVERAL DIFFERENT TYPES OF TISSUES
ARE FOUND GROUPED TOGETHER TO FORM ORGANS,
AS WE CAN SEE HERE IN A SLICE OF A DISEASE-FIGHTING ORGAN
CALLED A LYMPH NODE.
BEYOND THAT, CERTAIN ORGANS COMBINE TO FORM ORGAN SYSTEMS,
WHICH, WHEN TAKEN TOGETHER, CREATE A WHOLE ORGANISM.
THE HUMAN ORGANISM HAS NINE BASIC ORGAN SYSTEMS.
THE FIRST IS THE SKELETAL SYSTEM,
WHICH GIVES THE BODY SUPPORT
AND HELPS PROTECT THE DELICATE INTERNAL ORGANS.
BONES ARE THE MAIN ORGANS OF THE SKELETAL SYSTEM.
THE SECOND IS THE MUSCULAR SYSTEM,
WHICH ALLOWS THE BODY TO MOVE.
THE MUSCLES ARE THE MAIN ORGANS OF THIS ORGAN SYSTEM.
THE THIRD IS THE NERVOUS SYSTEM, WHICH SENSES THE ENVIRONMENT,
RECEIVES INFORMATION FROM THE BODY,
HELPS COORDINATE PHYSICAL ACTIVITIES,
AND MAKES IT POSSIBLE TO THINK.
THE BRAIN IS THE MAIN ORGAN OF THE NERVOUS SYSTEM.
FOURTH IS THE CIRCULATORY SYSTEM
FOR CARRYING BLOOD TO CELLS THROUGHOUT THE BODY.
THE HEART IS THE MAIN ORGAN OF THE CIRCULATORY SYSTEM.
FIFTH IS THE EXCRETORY SYSTEM,
WHICH ALLOWS THE BODY TO RID ITSELF OF LIQUID WASTE.
THE KIDNEYS ARE THE MAIN ORGAN OF THE EXCRETORY SYSTEM.
SIXTH IS THE DIGESTIVE SYSTEM,
WHICH ALLOWS THE BODY TO PROCESS AND ABSORB FOOD AND WATER.
THE STOMACH, SMALL INTESTINE,
LIVER, PANCREAS, AND LARGE INTESTINE
ARE ALL IMPORTANT DIGESTIVE ORGANS.
SEVENTH IS THE ENDOCRINE SYSTEM,
WHICH IS MADE UP OF DIFFERENT GLANDS
THAT PRODUCE THE CHEMICAL MESSENGERS CALLED "HORMONES."
AMONG THE ORGANS IN THE ENDOCRINE SYSTEM
ARE THE THYROID, ADRENAL, AND PITUITARY GLANDS.
EIGHTH IS THE RESPIRATORY SYSTEM,
WHICH PROVIDES THE BODY WITH OXYGEN
AND HELPS IT GET RID OF THE WASTE PRODUCT CARBON DIOXIDE.
THE LUNGS ARE THE MAIN RESPIRATORY ORGANS.
THE NINTH AND LAST ORGAN SYSTEM IS THE REPRODUCTIVE SYSTEM,
WHICH ALLOWS US TO HAVE CHILDREN.
THE FEMALE OVARIES AND THE MALE TESTIS
ARE THE MAIN ORGANS OF THE REPRODUCTIVE SYSTEM.
AS WE HAVE SEEN,
ALL NINE OF THESE COMPLICATED ORGAN SYSTEMS...
IN THE NEXT SECTION OF THIS PROGRAM,
WE WILL LOOK INSIDE A SPECIALIZED CELL
AND LEARN HOW IT WORKS.
Source: Ancient Lights. (1998). Cells Working Together: Tissues and Organs [Video
Segment]. Available from http://www.discoveryeducation.com/ (A Segment of:
Understanding Cells)