Transcript Tissue - WHCI10Science

From Cells to Organisms
Cells Working Together
• Single Celled Organisms –
These include organisms such
as bacteria and yeast, and
they can survive on their own
without depending on other
cells.
• Animal Cells – These cells live
and work as part of a much
larger group of cells, and
quickly die if separated.
Levels of Organization
• All animals (incl humans) have bodies made up of
cells organized in a hierarchy (levels of organization
of increasing or decreasing complexity).
• The Hierarchy:
– Cells- the most basic unit of living things.
– Tissue- any group of similar cells that performs the
same specific function (eg. Muscle, bone, blood,
skin, nerve tissue).
– Organ- A structure made up of two or more types of
tissue that work together to complete a specific task.
– Organ System – One or more organs and other
structures that work together to perform a body
function.
– Organism – A complex individual that can perform
functions such as eat, breathe, move and reproduce.
Covering Tissue: Epithelium
•
Epithelial Tissue (epithelium): made up of tightly packed
cells that cover body surfaces and line the body’s internal
organs and cavities. This can be a single layer or many
layers of cells.
– Single Layer: A thin layer of epithelial tissue allows some materials
to pass though the layer (eg. Air sacs in the lungs have a single
layer which allows oxygen to be exchanged between sacs and
blood).
– Multiple Layers: A thick layer of epithelial tissue protects areas
that can suffer from injury (eg. Skin has many layers).
Connective Tissue
• Connective Tissue: Made up of both
specialized cells and non-living
substances.
– Blood – connects body systems by
bringing in oxygen and nutrients and
removing waste.
– Bone – made up of living bone cells
surrounded by hard non-living material.
– Ligaments- strong elastic tissue that
connects bones together.
– Tendons- tough, inelastic tissue that
attaches muscles to bones.
– Cartilage- a softer, cushioning pad like
tissue found at bone joints, as well as
other parts such as ears and nose.
Connective Tissue Injuries
• Achilles Tendon Injury
• Tennis Elbow
• Torn ACL (anterior cruciate ligament) – key
ligament holding the bones in the knee
together that can be harmed by
overstretching or suddenly twisting the knee.
Sensory Tissue
• Light-sensitive cells (retina) – tissue in the eye that responds to light in
the environment to transmit imagery information to the brain.
• Hair cells (in the cochlea) - tissue in the ear that senses sound vibrations.
• Nerve tissue - one of the most complex body tissues fund in the brain,
spinal chord, and making up the nerves.
– Sensory Neurons- tissue in the skin and other sensory organs that receives
information about the outside environment.
– Motor neurons- carry instructions from the brain or the spinal chord to the
another body part usually the muscles.
– Interneurons- The tissue that connects sensory and motor neurons (make up
the brain and spinal chord).
Responding: Muscle Tissue
• Muscle Tissue: Specialized tissue made up of cells
that shorten or contract to allow movement.
– Striated Muscle Tissue - muscle tissue that can be
voluntarily controlled to contract allow someone
to through a ball, walk or run (eg. Skeletal muscle)
– Smooth Muscle Tissue – the muscle tissue that
lines the walls of arteries, veins and body organs
and contacts involuntarily (eg. contractions in
stomach to assist digestion, or diaphragm
movement in lungs to allow breathing).
– Cardiac Muscle Tissue - A type of striated muscle
tissue that lines the walls of the heart and
contracts involuntarily.