Indiana Science Grade 7 Pages 14 - 21 Living Things Indiana Science Grade 7 Pages 14 - 21

Living Things How are living things, or organisms, alike? Living things are organized. The Cell – the smallest unit of an organism Each cell contains an orderly structure And contains genetic information Prokaryotic Cell – cell without a nucleus and other membrane-bound organelles Eukaryotic cell – cell with nucleus and other membrane-bound organelles

Living Things Living things respond. A stimulus – anything that causes some change in an organism. Response – the way an organism reacts to a stimulus. Example: Getting a leash out = dogs go crazy!! .Homeostasis – maintaining the proper conditions in a organism/cell.

Living Things Living things use energy. Living things reproduce. Autotroph = produces own energy (plant-like) Heterotroph = eats energy (animal-like) Living things reproduce.

Living Things Living things grow and develop. Growth of many-celled organism (multicellular) is due to an increase in the number of cells. Growth of a single-celled organism (unicellular) is due to an increase in the size of the cell. .Development – changes that take place during the life of an organism.

Living Things What do living things need? A place to live – habitat. .Raw materials – like water, proteins, fats, and sugars.

Living Things Where Does Life Come From? .Spontaneous Generation – early theory that living things could come from nonliving things; Was later disproved by Pasteur in mid-1800s.

Living Things .Biogenesis – theory that living things come only from other living things. Alexander Oparin’s hypothesis on the origins of life – gases on Earth’s early atmosphere combined to form complex compounds found in living things.

Living Things 4 Gases: .Ammonia .Hydrogen .Methane .Water Vapor Miller and Urey tested Oparin’s hypothesis and showed that chemicals (amino acids) found in living things could be produced.

Living Things Vocabulary Homeostasis Heterotroph Autotroph Unicellular Eukaryotic Cell Multicellular Prokaryotic Cell Stimulus Response