Transcript Grade 8 Science Unit 4:“Cells, Tissues, Organs & Systems”

Chapter 11: “Human body cells are
organized as tissues, organs and systems.”
• All systems have the following
characteristics:
1. Made up of individual parts that work
together as a whole
2. Often connected to one or more
systems
3. If one part of a system is missing or
damaged, the system will not function
well or may not function at all.
•Groups of similar cells
•Found in all multicellular
organisms
•Ex. Muscle tissue, nerve tissue,
epithelial tissue, etc.
•Groups of tissues. Made up of two or more types of
tissues. Ex:
•They are distinct structures that perform specific
functions.
•Ex. Lungs, kidneys, heart, etc.
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3, 4, 7, 8
•A group of organs that perform activities that
help the body as a whole.
•6 examples of organ systems are...
1. Digestive System
2. Circulatory System
3. Nervous System
4. Respiratory System
5. Excretory System
6. Muscular System
Consists of:
•Mouth
•Gall Bladder
•Small Intestine
•Liver
•Stomach
•Large Intestine
•Oesophagus
•Pancreas
•To take in and break down food, absorb nutrients, and
eliminate solid waste.
Consists of:
•Heart
•Arteries
•Veins
•Capillaries
Function:
•To transport blood, nutrients
(chemicals needed for survival), gases
and wastes.
Consists of:
•Brain
•Spinal cord
•Sense organs (eyes, ears, nose,
tongue, skin)
•Nerves
Function:
•To detect changes in the environment and to signal
these changes to the body which then carries out a
response.
Consists of:
•Nasal cavity
•Trachea
•Lungs
Function:
•To control breathing, and exchange gases in
lungs and tissues.
Consists of:
•Lungs
•Kidneys
•Urinary bladder
Function:
•To remove liquid and gas wastes from
the body
Consists of:
•Muscle tissue connected to bones
throughout the body.
Function:
•To work with the bones to move
body parts
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1. The parts of a system must work together and be able
to interact with other systems. If part of the system
operates incorrectly, the system may operate
incorrectly or fail.
3. A (c) (muscle tissue)
B (b) (nerve tissue)
4. Tissues are composed of cells that have the same
structure and function. Organs are made up of
different types of tissues working together.
7. – muscle tissue: elastic bands or other stretchy material that is
able to expand and contract
– epithelial tissue: some smooth fabric or material that could be
used to line a cavity. The smooth surface faces out into the cavity.
– connective tissue: some hard, solid material that holds its shape,
such as clay or Plasticine.
– nerve tissue: a webbed material or cotton that is pulled apart. The
tissue should be able to hold the shape of a web or a net.
8. B, D, C, E, A. The heart cell (B) is organized into cardiac tissue
(D), then into an organ (the heart) (C), then into an organ
system (the circulatory system) (E), then finally into a human
(A).
1. digestive system; circulatory system; nervous system;
respiratory system; excretory system; muscular system;
skeletal system; immune system; endocrine system;
integumentary system; and reproductive system.
2. (a) circulatory system (b) digestive system (c) excretory
system (d) respiratory system (e) respiratory
system/digestive system
3. The digestive system provides the body with all the matter
and energy it needs to live.
4. From left to right: circulatory system; muscular system;
nervous system.
5. The excretory system filters wastes from the blood and
flushes it from the body. The circulatory system carries
gaseous wastes from the cells and takes them to the lungs
where they are exchanged for nutrients and oxygen.
6. (a) the digestive system
(b) No, the respiratory system also connects the internal
and external environment. It is responsible for
exchanging gases and wastes from cells inside the body
with oxygen from outside the body.
(c) The digestive system fits inside the body because the
intestines (particularly the small intestine) are tightly
folded many times into a small area.
Tissues
Organism
2.
Cells
Organs
Organs
Systems
6. The cell needs to move materials,
into and out of the cell, just as an organism needs to move
materials into and out of the body. Body systems such as
the digestive system and the circulatory system act to carry
waste away from cells and to bring nutrients and oxygen to
the cells.