Characteristics of Life Tuesday, December 08, © Ryan Barrow 2008

Objectives Tuesday, December 08,

Characteristics of Life There is no one definition of life that is accepted by scientists. There is no one definition of life that is accepted by scientists. However, life is defined by the properties and functions characteristic of living things However, life is defined by the properties and functions characteristic of living things Life Functions {Properties of Life} are the various activities carried on by living things. Life Functions {Properties of Life} are the various activities carried on by living things. Tuesday, December 08, © Ryan Barrow 2008

Properties of Life Order Order Reproduction Reproduction Growth and Development Growth and Development Nutrition Nutrition Energy Utilization Energy Utilization Respiration Respiration Response to Stimuli Response to Stimuli Tuesday, December 08, © Ryan Barrow 2008

Order All other characteristics of life emerge from an organism’s complex organization All other characteristics of life emerge from an organism’s complex organization Made up of cells Made up of cells A single cell can be an organism A single cell can be an organism Bacteria Bacteria Unicellular Unicellular Most organisms are multicellular Most organisms are multicellular Tuesday, December 08, © Ryan Barrow 2008

Energy Utilization Energy is used to grow, develop and reproduce Energy is used to grow, develop and reproduce Anabolism Anabolism Process in a living thing that involves putting things together, or synthesizing complex substances from simpler substances Process in a living thing that involves putting things together, or synthesizing complex substances from simpler substances Photosynthesis Photosynthesis Photo = Light Photo = Light Synthesis = put together Synthesis = put together Tuesday, December 08, © Ryan Barrow 2008

Energy Utilization #2 Catabolism Catabolism Changing complex substances into simpler ones Changing complex substances into simpler ones Results in a release of energy Results in a release of energy Can animals perform photosynthesis? Can animals perform photosynthesis? Metabolism Metabolism The total sum of all chemical reactions in the body The total sum of all chemical reactions in the body The balance of anabolism and catabolism The balance of anabolism and catabolism Tuesday, December 08, © Ryan Barrow 2008

Growth and Development Growth involves the increase in cell number and cell size Growth involves the increase in cell number and cell size What growth spurt are you going through right now? What growth spurt are you going through right now? When does an organism stop growing/developing? When does an organism stop growing/developing? What tells our body that it is time for a cell to die? What tells our body that it is time for a cell to die? How often do humans replace every cell in their body? How often do humans replace every cell in their body? Growth-->Aging-->Death Growth-->Aging-->Death How can you tell when a tree has died?` How can you tell when a tree has died?` Tuesday, December 08, © Ryan Barrow 2008

Reproduction The sexual or asexual process by which organisms generate new individuals of the same kind. The sexual or asexual process by which organisms generate new individuals of the same kind. Cellular Cellular Asexual Asexual The Cell Cycle The Cell Cycle Mitosis Mitosis Sexual Sexual Meiosis Meiosis Organism Organism Asexual Asexual Budding Budding Sexual Reproduction Sexual Reproduction Sex Sex Tuesday, December 08, © Ryan Barrow 2008

Organism Sexual Reproduction* Plants Dicotyledon Dicotyledon A type of flowering plant that contains both sperm and eggs A type of flowering plant that contains both sperm and eggs Tuesday, December 08, © Ryan Barrow 2008

Organism Sexual Reproduction *Plants Fertilization Fertilization Self Pollination Self Pollination Transfer of pollen (sperm) from an anther to a stigma of the same flower. Transfer of pollen (sperm) from an anther to a stigma of the same flower. Tuesday, December 08, © Ryan Barrow 2008

Sexual Reproduction Plants Fertilization Fertilization Cross Pollination Cross Pollination The transfer of pollen from an anther of the flower of one plant to a stigma of the flower of another plant. The transfer of pollen from an anther of the flower of one plant to a stigma of the flower of another plant. Tuesday, December 08, © Ryan Barrow 2008

Response to Stimuli/Environment Involves behaviors, metabolism and growth Involves behaviors, metabolism and growth What are some environmental pressures that you, as a human, respond to? What are some environmental pressures that you, as a human, respond to? Odors Odors Light Light Sound Sound Temperature Temperature Tuesday, December 08, © Ryan Barrow 2008

Response to Stimuli/Environment II Homeostasis Homeostasis Process by which organisms respond to stimuli in ways that keep their body suitable for life Process by which organisms respond to stimuli in ways that keep their body suitable for life Refers to an organism’s ability to maintain a constant or stable condition Refers to an organism’s ability to maintain a constant or stable condition Regulation mechanism to maintain an organisms internal environment Regulation mechanism to maintain an organisms internal environment Provides capacity to evolve--”micro-evolution” Provides capacity to evolve--”micro-evolution” How does the human body respond in a hot environment? How does the human body respond in a hot environment? What household appliance provides a great example of homeostasis? What household appliance provides a great example of homeostasis? Tuesday, December 08, © Ryan Barrow 2008