Cell Organization

• Many-celled organisms are not just mixed-up collections of different types of cells.

• Cells are organized into systems that, together, perform functions that keep the organism healthy and alive.

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organelle

• Parts of a cell that have a special job found inside in the cytoplasm

• Ex. nucleus

• vacuole

• mitochondria

• chloroplast

cell• Smallest unit of life

• Ex. Bone cell, muscle cell, nerve cell, etc.

Tissues and Organs

• Cells that are alike are organized into tissue (TIH shewz).

• Tissues are groups of similar cells that all do the same sort of work.

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Blood is a Tissue

Tissues

• Ex.

• Blood made of blood cells

• Bone tissue made of bone cells

Tissues and Organs

• Different types of tissues working together can form a structure called an organ (OR gun).

• The stomach is an organ that includes muscle tissue, nerve tissue, and blood tissue.

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• Other human organs include the heart and the kidneys.

Organs Systems• A group of organs that work together to do

a certain job is called an organ system. • Organ systems found

in your body include the respiratory system, the circulatory system, the reproductive system, and the nervous system.

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Organ systems

• Nervous system includes the brain, nerves and spinal cord

• Respiratory system is the nose, trachea, and lungs

Organs Systems

• Organ systems also work together.

• For example, the muscular system has more than 600 muscles that are attached to bones.

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• The contracting cells of muscle tissue cause your bones, which are part of the skeletal system, to move.

organism

• A living thing

• Ex. Humans, trees, grass animals

Smallest to largest-order from top to bottom

tissue, organ system, cell, organism, organ, organelle (cell part)

Smallest to largest

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Question 2

Which is the correct order of cell organization?

A. cell, tissue, organ system, organB. cell, organ, tissue, organ systemC. cell, tissue, organ, organ systemD. tissue, cell, organ, organ system

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Answer

The answer is C. Cells are organized into systems that, together, perform functions that keep the organism alive.