Download How do cells work together? Chapter 1 lesson 2

Specialized cells and tissues
• Single-celled organisms have only one cell
• Multicellular organisms are made up of many
kinds of cells that have different functions.
• Tissues are specialized cells with similar
structures and functions
– There are four tissue types in the human body
• Epithelial tissue
• Connective tissue
• Muscle tissue
• Nerve tissue
Epithelial tissue
• Epithelial tissue contains
cells that are packed
tightly together.
– Examples: outer layer of
skin, lining of air passages,
lining of internal organs
Connective tissue
• Connective tissue adds support and structure
to the body, fills spaces, and stores fat.
– Examples: blood, bone, cartilage, and fat cells
Muscle tissue
• Muscle tissue is like elastic. Its job is to
contract and relax. There are three types of
muscle tissue:
– Skeletal muscle- moves the bones of the skeleton
when directed by the brain
– Smooth muscle does involuntary movements- like
breathing
– Cardiac muscle contracts to move blood around
the body
Here are a few organs…
– The brain is often compared to a computer
– The heart works like a pump to send blood
through your body
– Blood vessels are like pipelines that transport
blood
– Lungs enable you to breathe to take oxygen your
cells need. They supply oxygen and remove
carbon dioxide from the blood
– Sense organs help you react to your
surroundings: ears, eyes, nose, tongue, and skin
• The liver produces chemicals that flow into the small intestine to
help in digestion. It also helps remove toxins from the blood
• The pancreas contains tissues that produce enzymes that aid
digestion
• The stomach has smooth muscle tissue that contracts, squeezing
the food to break it into smaller pieces.
Organ Systems
• A system is a group of organs that work
together to perform a specific function.
• Many of these systems are easily recognized
by their names…can you guess what they do?
Plants organ systems
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