CHAPTER 1 – THE NATURE OF LIFE

THE NATURE OF LIFE

THE NATURE OF LIFE

• MARS VS EARTH (WHAT’S THE BIG DEAL?!?)

THE NATURE OF LIFE

• BIOLOGY– THE STUDY OF LIVING THINGS

THE NATURE OF LIFE

• WHAT DOES IT MEAN TO BE ALIVE??– THERE IS NO EASY ANSWER/DEFINITION TO THIS

QUESTION…SO WHAT CAN WE DO TO FIGURE OUT IF SOMETHING IS “ALIVE”??

THE NATURE OF LIFE

• WE DEFINE SOMETHING AS BEING ALIVE (AN ORGANISM) IF IT HAS THE FOLLOWING CHARACTERISTICS:– LIVING THINGS ARE HIGHLY ORGANIZED AND CONTAIN MANY

COMPLEX CHEMICAL SUBSTANCES– LIVING THINGS ARE MADE UP OF ONE OR MORE CELLS– LIVING THINGS USE ENERGY– LIVING THINGS HAVE A DEFINITE FORM AND A LIMITED SIZE– LIVING THINGS HAVE A LIMITED LIFE SPAN– LIVING THINGS GROW– LIVING THINGS RESPOND TO CHANGES IN THE ENVIRONMENT– LIVING THINGS ARE ARE ABLE TO REPRODUCE– GROUPS OF LIVING THINGS CHANGE OVER TIME (EVOLUTION)

THE NATURE OF LIFE

• SAY HELLO TO THE EBOLA VIRUS…– IS IT ALIVE??– DOES IT MEET

ALL THECRITERIA MENTIONEDPREVIOUSLY??

THE NATURE OF LIFE

• WE DEFINE SOMETHING AS BEING ALIVE (AN ORGANISM) IF IT HAS THE FOLLOWING CHARACTERISTICS:– LIVING THINGS ARE HIGHLY ORGANIZED AND CONTAIN MANY

COMPLEX CHEMICAL SUBSTANCES - CHECK– LIVING THINGS ARE MADE UP OF ONE OR MORE CELLS - CHECK– LIVING THINGS USE ENERGY - CHECK– LIVING THINGS HAVE A DEFINITE FORM AND A LIMITED SIZE - CHECK– LIVING THINGS HAVE A LIMITED LIFE SPAN - CHECK– LIVING THINGS GROW - CHECK– LIVING THINGS RESPOND TO CHANGES IN THE ENVIRONMENT -

CHECK– LIVING THINGS ARE ARE ABLE TO REPRODUCE – FAIL!!

THE NATURE OF LIFE

• NON-LIVING THINGS MAY EXHIBIT SOME OF THE CHARACTERISTICS LISTED, BUT UNLESS ALL OF THEM ARE PRESENT…IT IS CONSIDERED A NONLIVING THING

THE NATURE OF LIFE

• ANOTHER WAY TO DETERMINE IF SOMETHING IS LIVING IS IF IT PERFORMS ALL OF THE…

•LIFE PROCESSES

THE NATURE OF LIFE

• LIFE PROCESSES =

H.N.T.R.S.G.E.R.M.R. (“HUNTERS GERMER”)

THE NATURE OF LIFE

• H = HOMEOSTASIS

• N = NUTRITION

• T = TRANSPORT

• R = RESPIRATION

• S = SYNTHESIS

• G = GROWTH

• E = EXCRETION

• R = REGULATION

• M = METABOLISM

• R = REPRODUCTION

THE NATURE OF LIFE

• HOMEOSTASIS– MAINTAINING A

STABLE INTERNALENVIRONMENT

– “FEEDBACK” MECHANISMS

THE NATURE OF LIFE

• NUTRITION– TAKING MATERIALS FROM THE EXTERNAL ENVIRONMENT

AND TURNING THEM INTO FORMS YOU CAN USE– AUTOTROPHIC

VS.HETEROTROPHIC

– INGESTION VS.DIGESTION VS.EGESTION

THE NATURE OF LIFE

• TRANSPORT– THE PROCESS BY WHICH

SUBSTANCES ENTER ANDLEAVE CELLS AND BECOME DISTRIBUTED WITHIN THE CELLS

– *CIRCULATORY SYSTEM*• SPECIALIZED SYSTEM TO ALLOW

FOR TRANSPORT

THE NATURE OF LIFE

• RESPIRATION– BREATHING

VS.CELLULARRESPIRATION

– AEROBIC VS.ANAEROBIC

THE NATURE OF LIFE

• SYNTHESIS– COMBINING

SIMPLE SUBSTANCESTO FORM LARGER, MORE COMPLEX SUBSTANCES

THE NATURE OF LIFE

• GROWTH– PROCESS

BY WHICHORGANISMSINCREASE IN SIZE(EITHER # OF CELLS,OR SIZE OF CELL)

THE NATURE OF LIFE

• EXCRETION– THE REMOVAL OF

METABOLIC WASTES

THE NATURE OF LIFE

• REGULATION– ALL THE

ACTIVITIESTHAT HELPAN ORGANISMMAINTAINHOMEOSTASIS

– A.K.A“RESPONSE”

THE NATURE OF LIFE

• METABOLISM– ALL THE

CHEMICALREACTIONS(RxNS) THATOCCUR IN THE BODY

THE NATURE OF LIFE

• REPRODUCTION– THE PROCESS

BY WHICHLIVING THINGSPRODUCE NEWORGANISMSOF THEIROWN KIND

– ASEXUAL VS.SEXUAL

– *ONLY PROCESS THAT ISNOT NECESSARY FOR INDIVIDUAL*

THE NATURE OF LIFE

• ALWAYS REMEMBER…

•H.N.T.R.S.G.E.R.M.R

THE NATURE OF LIFE

• NEXT TIME…WE TALK ABOUT WHYI, AND YOU, LOVE SCIENCE

• LEARN TO THINK, AND ACT, LIKE ASCIENTIST