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Life Processes. What are the characteristics of life?. LIFE PROCESSES. Looking at living things. What is a living thing?. Imagine that you are space traveler who lands on an unknown planet. How could you determine if what you are looking at is alive. Ex. A rock and a blade of grass.
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Life Processes What are the characteristics of life?
LIFE PROCESSES Looking at living things
What is a living thing? • Imagine that you are space traveler who lands on an unknown planet. How could you determine if what you are looking at is alive. Ex. A rock and a blade of grass.
What are the life processes? • NUTRITION • TRANSPORT • RESPIRATION • EXCRETION • SYNTHESIS • GROWTH • REGULATION • REPRODUCTION
Key Concepts • Metabolism– The sum total of all the life functions. • Homeostasis – the maintenance of a stable internal environment in spite of changes in the external environment. Ex: Your body sweats in order to maintain a proper internal temperature.
Nutrition • Includes the activities involved in ingestion(obtaining food from the environment) and digestion(processing food for use by the organism). It also includes egestion(removal of solid wastes)
Nutrition – Egestion in Leukocytes • in which the bacteria, having been ingested and enclosed in a digestive vacuole by the leukocyte, are ejected by the living cellto the outside
TRANSPORT • The absorption of materials through cell membranes and the circulation, or distribution of materials to all the cells of an organism.
Elodea cells Human Circulation TRANSPORT
RESPIRATION • The process of releasing energy from organic molecules for use by cells. • During respiration glucose is broken down, and the energy released is stored in the compound ATP. • Energy released by the compound ATP is used by organisms to perform life functions.
Plants and animals use the oxygen in the air to turn food into energy. RESPIRATION
EXCRETION • The elimination of cellular waste products from the organism. • These wastes include water, carbon dioxide, salts, and nitrogen-containing compounds.
Urine Sample EXCRETION
SYNTHESIS • Chemical reactions in which small molecules combine to form larger ones. • When big things are made from small things.
SYNTHESIS • Combining 2 glucose molecules to make a larger maltose molecule
GROWTH • An increase in size brought about by increases in cell size and cell number. • The raw materials for growth are the products of synthesis.
REGULATION • The control and coordination of life functions. • Responding to changes in the environment to maintain homeostasis. Ex: Your eyes immediately adjusting to the outside light after watching a movie.
Nucleus Brain REGULATION
All living things respond to changes. Living things notice changes in their surroundings and react to them. Eg. Plants grow towards the light. Eg. People react to the temperature around them.
REPRODUCTION • The production of new individuals. • Reproduction is necessary for the survival of a species, or kind of organism.