DETERMINING THE BASIS OF LIFE AGRISCIENCE AND TECHNOLOGY Modified by Georgia Agricultural Education Curriculum Office July, 2002

CHARACTERISTICS OF AN ORGANISM 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.

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.

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

LIFE IS CLASSIFIED AS LIVING AND NONLIVING LIVING PLANTS ANIMALS 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

LIFE PROCESSES OF ORGANISMS Getting and using food Movement Circulation Respiration Growth and Repair Secretion Sensation Reproduction

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)

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

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

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

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

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

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

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)