Chapter 2: Characteristics of Life. Write the following notes down (all of them).
All organisms are made of cells.
Cell-a membrane covered structure that has all necessities for life.
Unicellular – one celled organisms (bacteria and some algae).
Multicellular – organisms made up of more than one cell.
Stimulus – Any change that affects the activity of an organism.
Homeostasis – maintaining a stable internal environment.
Sexual Reproduction – requires two parents and the offspring gets some traits from both
parents.
Asexual Reproduction – requires ONLY one parent to produce offspring. (Bacteria,
Hydra, Algae).
DNA – Deoxyribonucleic Acid – this is the blueprint of your genes that is used to make
proteins and may be passed on to offspring.
Heredity – the passing of traits from one generation to the next or from parents to
offspring.
Every organism must use energy to survive.
Metabolism - All the chemical reactions that keep an organism alive or the chemical
reactions that an organism performs.
All Living things must grow and develop as they live.
All living organisms have 4 necessities for life: Water, Air, Food, A place to live
(shelter).
Producers – organisms that make their own food (plants and some algae).
Consumers – organisms that MUST eat or consume other organisms for food.
Decomposers – organisms that get their food from breaking down the nutrients found in
DEAD organisms. (bacteria, fungi)
Proteins – large molecules made up of AMINO ACIDS. Enzymes help chemical
reactions occur in an organism. Enzymes are special proteins.
Carbohydrates – two types: 1) simple – made up of one or a few sugars linked
together.(fruit sugars and table sugar) 2) Complex – made up of many to hundreds of
sugars linked together. (Starches like potatoes, bread, and pasta).
Lipids – fats and oils. They are used to make cell membranes and for energy.
Phospholipids – special lipids that are used to make cell membranes.
ATP – Adenosine Triphosphate – the energy that cells must have and they get it from
breaking down GLUCOSE a simple sugar.
Nucleic Acids – the building blocks of DNA and they are made up of nucleotides.