Anatomy and Physiology
Every individual living thing is made of smaller parts. The smaller parts have different functions, but all of the parts work together to enable the individual to live and survive in its environment. The smaller parts are made of even smaller parts, which are made of smaller parts, and smaller parts, until you reach the smallest part of all: the cell. The cell is the basic building block of all living things.
Cells Alive
Cell Structure and Functions
Some tiny organisms, called protists, are made of only one cell. Since the single cell must work alone, it has to do everything to make sure that the organism survives. Protists can not be seen with the human eye. To observe tiny organisms in their microworlds, you can use a microscope.
Microworlds
Extremophiles
Multi-celled organisms are more complex. Different parts have different functions, each part sharing the work and cooperating to make sure that the organism survives.
In a plant, for example, the cells working together in the roots make sure that the plant gets the water and nutrients from the soil that the plant needs to survive. The cells working together in the leaves make sure that the plant exchanges oxygen for the carbon dioxide that the plant needs to survive. The roots and the leaves work together as a system for the plant to survive.
Virtual Plant Cell
Plant Cell Structure
Leaf Structure
Plant Sciences Institute
Plant Galls
The World of Trees
TreeGuide
In Search of Green Life
Parts and Pieces
Identify pieces of mushrooms and mealworms.
The parts of an animal also work together to make sure that the animal is able to survive in its environment. An animal's anatomy must be adapted for its survival. Monkeys have strong arms and legs and hand-like feet so that they can climb trees easily to get food. Chameleons are well-known for their ability to change skin color to blend in with their environment, hiding from their enemies. The anatomy of the chameleon also features two eyes that can move independently, enabling the side of the body facing an enemy to remain perfectly still while the other side keeps watch.
Skull Collection
Animal Omnibus
Worm World
Watch worms at work in their world. Observe how they adapt to and behave in their environment.
Different parts have different functions, but all of the parts work together to help the animal survive. Some parts are responsible for allowing the animal to reproduce. The reproductive organs on an animal also determine its gender. Often, male and female animal anatomy varies. Were the earthworms male or female? Actually, neither. Earthworms are hermaphrodites, which means that they have both male and female reproductive organs. Their eggs and sperm are released in a protective mucus sheath which slips over the worm's head and is deposited in the soil.
Earthworms
Worms
--------------------------------------------------------------------------------
Questions?
If you didn't find the answers to your life science questions, try searching Ask A Scientist.
Career Connections:
If you're interested in "Anatomy and Physiology," consider one of these career possibilities: Botanist, Veterinarian, Health-Related Careers, Field Biologist
Keywords and Cross-References:
adaptation (eating), adaptation (climate), adaptation (environment), anatomy, cells, earthworms, hermaphrodite, mealworms, microscope, organisms, physiology, protists, reproduction (flowering plants), reproduction (classification), skulls, structures (plant classification), systems
--------------------------------------------------------------------------------
Curriculum Connections:
Macmillan/McGraw-Hill:
Unit 10, Lesson 3
Unit 17, Lesson 4
National Science Education Standards:
K-4 Life Science Content Standard C
5-8 Life Science Content Standard C
K-4 Science as Inquiry Content Standard A
5-8 Science as Inquiry Content Standard A
Earthworms
--------------------------------------------------------------------------------