Download Classifying Living Things A2-A11

Notes for Unit A Characteristics of Living Things
Chapter 1 Classifying Living Things p. A2-A11
What is the basic unit of life? (p. A6)
-organism= any living thing
-cell= smallest part of an organism; works to keep living thing alive
-chlorophyll= green chemical inside plant cells that let plants make their own food using
the sun’s energy
Plant and animal cells (p. A6-A7)
-ONLY plant cells have the following parts:
 chloroplasts =part that contains chlorophyll
 cell wall =rigid structure around the whole cell
 vacuole= stores food, water, waste
-BOTH plant and animal cells have the following parts:
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Nucleus= control center of cell (brain)
Cytoplasm= fluid inside cell where all the parts float
Mitochondria= releases energy into cell
Cell membrane= holds the cell together
What are living things made of? (p. A8-A9)
-single cell organisms include bacteria and some fungi
-many-celled organisms work together doing different jobs to keep the organism alive,
like algae, trees, animals (humans)
-tissue= similar cells that have the same job working together (examples celery stalks in a
plant or muscles in an animal)
-organ= tissues of different kinds coming together (examples- heart, lungs, brain in
animals)
-organ system= group of organs that work together to do a certain job (examples- fox’s
digestive system includes mouth, stomach, and intestines)
What traits are used to classify organisms? (p. A10)
-classification= science of finding patterns among living things
-Aristotle first classified plants into 3 groups by size (herbs, shrubs, and trees)
-today we classify organisms by looking at their cells, tissues, organs, and organ systems
and trying to find out what is the same and different