Concepts and Origin of Life

CONCEPTS AND ORIGIN OF LIFE

Earth and Life Science AY 22-23

LEARNINGLEARNING
TARGETSTARGETS

I can explain the evolving
concept of life based on
emerging pieces of
evidence.
I can describe classic
experiments that model
conditions which may
have enabled the first
forms of life.

How do all living thingsHow do all living things
evolve from simple toevolve from simple to

complex life forms?complex life forms?

Question to Ponder on...Question to Ponder on...

Cosmozoic/PanspermiaCosmozoic/Panspermia
TheoryTheory

Spontaneous OriginSpontaneous Origin

(Biochemical Theory)(Biochemical Theory)

Special CreationSpecial Creation

THREETHREE

POSSIBILITIESPOSSIBILITIES

OF THEOF THE

ORIGIN OFORIGIN OF

LIFELIFE

Life may have been placed on earthLife may have been placed on earth
by supernatural/ divine forces.by supernatural/ divine forces.

Special CreationSpecial Creation

Life may have been seeded by life-formsLife may have been seeded by life-forms
from another planet.from another planet.
Proof: discovery of organic molecules inProof: discovery of organic molecules in
remnants and artifacts of meteorite samples.remnants and artifacts of meteorite samples.

Cosmozoic/PanspermiaCosmozoic/Panspermia
TheoryTheory

Life may have evolved from inanimateLife may have evolved from inanimate
matter.matter.

Spontaneous OriginSpontaneous Origin
(Biochemical Theory)(Biochemical Theory)

Frozen OceanFrozen Ocean
Underneath Earth’s crustUnderneath Earth’s crust
Clay on Earth’s CrustClay on Earth’s Crust
Vents in deep seaVents in deep sea

Below are some hypothesisBelow are some hypothesis
of its origin:of its origin:

Spontaneous OriginSpontaneous Origin
(Biochemical Theory)(Biochemical Theory)

MAJOR EVENTS

BILLION

OF YEARS

AGO

Rapid diversification of animals; plants and fungi appear,

origin of humans about two million years ago
0.5

Earliest animals; first multicellular organisms; diverse protists

1.0

First Eukaryotes

1.5

Diverse and abundant bacteria

2.0

Oxygen-forming photosynthesis begins

2.5

Diverse bacteria

3.0

First bacteria

3.5

Oldest rocks

4.0

Earth Forms

4.5

GeologicGeologic
Time ScaleTime Scale
Since theSince the
FormationFormation

of theof the
EarthEarth

Suggests that life arose
gradually from inorganic
molecules with “building blocks”
like amino acids forming first
and then combining to make
complex polymers.

Oparin and Haldane
Hypothesis

Primitive Earth’s Atmosphere

Proposed by Oparin and

Haldane

Tested through Miller – Urey

Experiment

The Most Remarkable:

Spontaneous Origin

ManifestationManifestation
of Lifeof Life

Earth and Life Science AY22-23

Learning Targets

I can describe how unifying themes (e.g.
structure and function, evolution, and
ecosystems) in the study of life show the
connections among living things and
how they interact with each other and
with their environment.

Characteristics of Living ThingsCharacteristics of Living Things

Characteristics ofCharacteristics of

Living ThingsLiving Things

Orderly Structure

Atoms > simple inorganic molecules > complex biological molecules

Organism < Organ system < organs< tissues < cells < organelles

Population > community > ecosystem > biosphere

Cellular organization

Unicellular- bacteria,

protozoa, fungi
(Paramecium)

Multicellular- fungi, plant,

animal cell

Characteristics ofCharacteristics of

Living ThingsLiving Things

Anabolism (growth and repair)

Catabolism (digestion)

Living things use energy

Metabolism

Plants (geotropism, phototropism)
React/respond to stimuli

Characteristics ofCharacteristics of

Living ThingsLiving Things

Grow and Develop

Reproduce

Characteristics ofCharacteristics of

Living ThingsLiving Things

Coded by Genes

Evolve and adapt to their environment

Types of Organism based on Number of Cells

Types of Cells Based on Presence of Nucleus

Types of Organisms based on Domains/ Divisions of Life

Common Parts of all types of Cells

Unicellular
Multicellular

Prokaryotic
Eukaryotic

Archaea
Bacteria
Eukarya

Cell Membrane

Cytoplasm

DNA/ Genetic Code

Ribosomes