Download AG-BAS-02.471-05.1p a-Determining_the_Bases_of_Life

DETERMINING THE BASES
OF LIFE
AGRISCIENCE AND
TECHNOLOGY
Modified by Georgia Agricultural Education Curriculum Office
July, 2002
August 2008
CHARACTERISTICS OF AN
ORGANISM
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August 2008
Chemically and structurally unique
Need energy
Have a life span
Are capable of growth and reproduction
Respond to their environment
PROTOPLASM
• Only form of matter in which
life exists
• Made up of water and proteins
• Chemical activity in
protoplasm determines the
kind of life and nature of the
organism
• Example: When a farmer
applies fertilizer to a plant he is
helping protoplasm carry out
more chemical activity.
August 2008
PHOTOSYNTHESIS
• Plants have the
capacity to manufacture
their food through
photosynthesis.
• Food is broken down
into energy that is used
to support life
processes.
• Animals depend on
plants as sources of
food.
August 2008
FIVE STAGES OF LIFE
• BEGINNING: Varies between species
• GROWTH : Occurs when an organism is young
and immature
• MATURITY: When the organism is fully
developed
• DECLINE : Loses its ability to maintain itself
• DEATH : Protoplasm ceases to carry out
chemical activity
August 2008
LIFE IS CLASSIFIED AS
LIVING AND NONLIVING
• LIVING
• PLANTS
• ANIMALS
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NONLIVING
CLAY
IRON ORE
LIMESTONE ROCK
COAL
OIL
ORGANISMS RESPOND TO
THEIR ENVIRONMENT
• RICE : Needs warm climate and requires
lots of water
• BANANAS : Requires tropical climate
• WHEAT : Winter wheat is cold tolerant;
can be planted in the fall
• TROUT: Need cold fresh water
• BEEF CATTLE : Some breeds suited for
warm or cold climates
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LIFE PROCESSES OF
ORGANISMS
• Getting and using
food
• Growth and Repair
• Secretion
• Movement
• Sensation
• Circulation
• Reproduction
• Respiration
August 2008
PARTS OF A PLANT CELL
• CELL MEMBRANE :
Surrounds the cell and
controls the movement of
materials into and out of
the cell.
• NUCLEUS : Controls the
cell activity (contains the
chromosomes and DNA)
• CYTOPLASM: Thick
solution that flows in a
cell (contains organelles)
August 2008
CELL SPECALIZATION
• Involves differences in cells so the cells
can perform unique activities for the
organism
• TISSUES: Groups of cells that are alike in
activity and structure; muscle, skin, nerves
and bones are examples.
• ORGANS : Collection of tissues that work
together to perform certain function ; heart,
lungs, stomach and liver are examples
August 2008
CELL SPECIALIZATION CONT.
• ORGAN SYSTEMS : Made up of several
organs which work together to perform an
activity; digestive system is made up of the
mouth, stomach, small intestine, large
intestine and others.
• Found in complex animal organisms
August 2008
HEREDITY
• IS THE PASSING OF THE TRAITS OF
PARENTS TO OFFSPRING
• Asexual reproduction - offspring is identical to
the parent (involves only one parent)
• Example: plants produced by cuttings
• Sexual reproduction - offspring exhibits traits of
both parents; variations occur
• Example: milk production in cattle
August 2008
GENETICS
• THE STUDY OF HEREDITY IN PLANTS
AND ANIMALS
• STUDY GENE COMBINATIONS /
RESULTED IN GENE ENGINEERING
• STUDY CELL DIVISION / RESULTED IN
NEW VARIETIES OF CROPS AND
IMPROVED NUTRIENTS FOR PLANTS
AND ANIMALS
August 2008
APPROACHES USED TO
IMPROVE ORGANISMS
• CONTROLLED BREEDING : Involves
breeding plants or animals to achieve
certain characteristics in the offspring.
• Examples are cattle that grow faster or
wheat varieties that produce more yields
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METHODS OF CONTROLLED
BREEDING
• SELECTION : Selecting desirable traits in
parents to pass on to offspring
• INBREEDING : Involves breeding offsping of the
same parents to each other ; used in plants and
animals.
• HYBRIDIZATION : Involves the crossing of two
different but closely related plants or animals ;
hybrid corn and hybrid striped bass are
examples
August 2008
THE OTHER APPROACH
USED TO IMPROVE
ORGANISMS
• GENETIC MANIPULATION : Involves an
artificial means of producing desirable
traits in plants and animals.
• Example would be the “Flavor Saver
Tomato” (gene identified causing rotting
processing inserted backwards increases
shelf life of tomatoes)
August 2008