Science SOL 5.5 Living Systems Mrs. Scott

Cells An organism is a living thing made up of cells. A cell is made of atoms and is the smallest unit of an organism that is capable of life. Cells are too small to be seen with the eye alone. Many parts of a cell can be seen using a microscope. Cells do different jobs and form tissues in your body.

Life Processes Cells carry out life processes. New cells come from existing cells. A life process is a function that living things must perform in order to stay alive. There are 6 life processes: Getting energy and nutrients (nutrients are substances needed for growth and survival) Using energy Reproduction (to make more of the same kind) Growing Some cells reproduce by dividing (skin, bone, blood) Some cells only grow larger (muscle) Getting rid of wastes Reacting to outside changes

Cell Parts & Functions Cell wall: the thick covering of a plant cell made of nonliving fibers. It makes up a kind of skeleton for the plant and allows water and gases to pass through tiny gaps (only found in plant cells.) Cell membrane: a thin, living cell covering that lets water, food, and gases in and out of the cell. Nucleus: the cell part that controls the activities of the other cell parts. The “brain” of the cell. Vacuole: storage sacs in the cell. Most of the space in a plant cell is filled with these tiny sacs of water. Cytoplasm: the jelly-like fluid between the cell membrane and the nucleus. All the other cell parts are located in the cytoplasm. Chloroplasts: tiny cell parts that contain chlorophyll. Chlorophyll is a green- colored material that gives plants their color and is used in the process of photosynthesis to make food for the plant. (Only found in plant cells.)

Animal and Plant Cell Parts The table below shows the cell parts of an animal & plant cell. You can see the parts that both have in common and the 2 more that a plant cell have.   Plant Cell Animal Cell Cell Membrane  Cytoplasm Nucleus Vacuole Cell Wall Chloroplast

Plant Cells Plant cells contain a nucleus, cytoplasm, cell wall, vacuoles, chloroplasts, & cell membrane. Plant cells tend to be rectangular in shape.

Animal Cells Animal cells contain a nucleus, cytoplasm, cell membrane, and vacuoles. Animal cells tend to be spherical or at times irregular in shape.

Classification Classify: to put objects into groups by a system.

Animal Classification Animals are classified into 2 groups: Invertebrates & Vertebrates Invertebrate- animal without a backbone Examples of invertebrates: octopus, worms, crabs, oysters, starfish, jellyfish Vertebrate- an animal with a backbone Examples of vertebrates: fish, amphibians, reptiles, birds, and mammals. (Snakes are vertebrates!!! They have backbones!)

Plant Classification Plants can be categorized as vascular & nonvascular. Most plants are vascular. Vascular plants- have special tissues to transport food and water. Examples: trees and flowering plants Nonvascular plants- do not have tissues to transport food and water. Examples: moss, liverworts, and hornworts

Plant Classification Vascular Plants Nonvascular Plants

Plant Classification