THE LIFE FUNCTIONS

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THE LIFE FUNCTIONS
Mrs. Woytowich The Living Environment
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OBJECTIVESUpon completion of this unit students
will be able to

• 1. Correctly identify and define the eight life
  functions of organisms
• Respiration
• Regulation
• Reproduction
• Excretion
• Growth
• Nutrition
• Transport
• Synthesis
•  
• 2. Explain the differences between each of the
  following
• Unicellular organisms Multicellular organisms
• Asexual Reproduction Sexual Reproduction
• Aerobic Respiration Anaerobic Respiration
• Absorption Circulation
• Autotrophic Nutrition and Heterotrophic Nutrition
• Ingestion vs. Digestion vs. Egestion
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• 3. Define the term metabolism and relate it to
  the functioning of an organism.

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 KEY TERMS

• Absorption
• Aerobic respiration
• Anaerobic respiration
• Asexual reproduction
• ATP
• Autotrophic nutrition

• Circulation
• Digestion
• Excretion
• Glucose
• Growth
• Heterotrophic nutrition
• Homeostasis
• Ingestion
• Insulin

• Metabolism
• Nutrients
• Nutrition
• Organism
• Regulation
• Respiration
• Sexual reproduction
• Synthesis
• Transport

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A. CHARACTERISTICS OF LIFE

• Biology is the STUDY OF LIVING THINGS
• All living things have ALL (not just some) of the
  characteristics of life.
• All living things show a great deal of DIVERSITY
  (DIFFERENCES) but also have many characteristics
  in common. In other words, they show UNITY
  (SIMILARITIES).
• Each living thing is called an ORGANISM.

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There are eight things that all living things
(ORGANISMS) have in common

• LIVING THINGS ARE HIGHLY ORGANIZED AND CONTAIN
  MANY COMPLEX SUBSTANCES
• LIVING THINGS ARE MADE UP OF ONE (UNICELLULAR) OR
  MORE (MULTICELLULAR) CELLS. A CELL IS THE
  SMALLEST UNIT OF LIFE
• LIVING THINGS USE ENERGY
• LIVING THINGS HAVE A LIMITED LIFE SPAN
• LIVING THINGS GROW
• LIVING THINGS RESPOND TO CHANGES IN THE
  ENVIRONMENT
• LIVING THINGS ARE ABLE TO REPRODUCE
• LIVING THINGS CHANGE OVER TIME

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• ALL LIVING THINGS POSSESS ALL OF THESE
  CHARACTERISTICS. NONLIVING THINGS ARE CLASSIFIED
  AS NONLIVING BECAUSE THEY DO NOT POSSESS ALL OF
  THEMALTHOUGH IT IS POSSIBLE FOR THEM TO POSSESS
  SOME!

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B. THE LIFE FUNCTIONS

• Scientists have been unable to agree on a single
  definition of life, but do agree on what the
  signs of life are. Thus, we will now discuss the
  8 life functions.
• What are they? R RESPIRATION
•  
• R REGULATION
•  
• R REPRODUCTION
•  
• E EXCRETION
•  
• G GROWTH
•  
• N NUTRITION
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• T TRANSPORT
•  
• S SYNTHESIS
•  
• R-R-R-E-G-N-T-S

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1. RESPIRATION

• INVOLVES RELEASING CHEMICAL ENERGY FOUND IN
  NUTRIENTS
• Organisms need materials and energy to stay ALIVE
• An organism uses energy and a constant supply of
  materials to PERFORM ALL LIFE FUNCTIONS
• The two types of respiration are
• Aerobic Respiration USES O2
• Anaerobic Respiration DOES NOT USE O2

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RESPIRATION
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2. REGULATION

• INVOLVES CONTROLLING AND COORDINATING VARIOUS
  ACTIVITIES
• Animals have
• Nervous system CARRIES NERVE MESSAGES
  (IMPULSES)
• Endocrine system - CARRIES CHEMICAL MESSAGES
  (HORMONES)
• Plants have PARTS THAT PRODUCE HORMONES, BUT NO
  NERVOUS SYSTEMS

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3. REPRODUCTION

• INVOLVES AN ORGANISM PRODUCING NEW ORGANISMS OF
  THE SAME KIND
• Is reproduction necessary for the continued
  existence of an organism? NO Is reproduction
  necessary for the continued existence of a
  species? YES-THE SPECIES WILL DIE OUT (EXTINCT)
  IF IT STOPS PRODUCING
• The two types of reproduction
• ASEXUAL - ONE PARENT ALL OFFSPRING IDENTICAL TO
  THE PARENT
• SEXUAL - TWO PARENTS OFFSPRING NOT IDENTICAL TO
  EITHER PARENT

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Can you identify the types of reproduction?
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4. EXCRETION

• INVOLVES THE REMOVAL OF WASTES FROM AN ORGANISMS
  BODY

NH3
NH3
H2O
H2O
H2O
H2O
NH3
H2O
NH3
(METABOLIC WASTES)
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5. GROWTH

• INVOLVES AN INCREASE IN SIZE
• There is a difference between growth and
  development

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• NUTRITION
• INVOLVES TAKING MATERIAL FROM THE ENVIRONMENT
• AND PUTTING IT INTO USABLE FORMS
• There are two types of nutrition
• Autotrophic Nutrition MAKE THEIR OWN FOOD
  (EXAMPLE
• PLANTS)
• Heterotrophic Nutrition CANNOT MAKE THEIR OWN
  FOOD
• Heterotrophic nutrition involves

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• TRANSPORT
• INVOLVES SUBSTANCES ENTERING AND LEAVING CELLS
• AND BECOMING DISTRIBUTED WITHIN CELLS
• Transport involves

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• SYNTHESIS
• SIMPLE SUBSTANCES ARE COMBINED TO MAKE COMPLEX
• SUBSTANCES

EXAMPLE Dehydration Synthesis
MONOSACCHARIDE MONOSACCHARIDE
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• C. METABOLISM
• ALL THE CHEMICAL REACTIONS OCCURRING WITHIN THE
  CELL(S) OF AN ORGANISM
• R R R E G N T S METABOLISM

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• D. HOMEOSTASIS
• THE CONDITION OF A CONSTANT, STABLE INTERNAL
  ENVIRONMENT
• Organisms need to keep their internal conditions
  relatively stable to survive (Examples fever,
  diabetes).
• The process of maintaining a stable internal
  environment is called HOMEOSTASIS
• If homeostasis is disrupted in a major way, an
  organism cannot survive!

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• E. EVOLUTION
• AS A GROUP (not individually), species change, or
  EVOLVE over time.
• F. BRANCHES OF BIOLOGY
• The many levels at which life can be studied
  include (from smallest to largest)
• CELLS ? TISSUES ? ORGANS ? ORGAN SYSTEMS ?
  ORGANISM ? POPULATION ? COMMUNITY ? ECOSYSTEM ?
  BIOSPHERE
• ?