Concept and Origin of Life

Concepts
of Life

Earth and Life Science AY 22-23

LEARNING
TARGETS

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.

Open Ended

Question to Ponder on...

How do all living things evolve from simple to complex life forms?

Cosmozoic/Panspermia
Theory

Spontaneous Origin

(Biochemical Theory)

Special Creation

THREE

POSSIBILITIES

OF THE

ORIGIN OF

LIFE

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

Special Creation

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

Cosmozoic/Panspermia
Theory

Life may have evolved from inanimate
matter.

Spontaneous Origin
(Biochemical Theory)

Frozen Ocean
Underneath Earth’s crust
Clay on Earth’s Crust
Vents in deep sea

Below are some hypothesis
of its origin:

Spontaneous Origin
(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

Geologic

Time Scale
Since the
Formation

of the
Earth

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
Alexander Oparin

John Burton Haldane

Harold Urey

Stanley Miller

Primitive Earth’s Atmosphere

Proposed by Oparin and

Haldane

Tested through Miller – Urey

Experiment

The Most Remarkable:

Spontaneous Origin

Oparin suggested that if the primitive atmosphere was reducing (oxygen-poor), and if there was an appropriate supply of energy such as lightning, then a wide range of organic compounds might be formed.

The experiment tested this hypothesis.

Miller passed a continuous electrical discharge simulating lightning through a mixture of gases (CH4, NH3, H2, andH2O), that were thought to make up the early Earth's atmosphere.

​

​Miller-Urey Experiment

Multiple Choice

Which of the following scientists suggested that life arose gradually from inorganic molecules.

• Oparin and Urey

• Oparin and Haldane

• Urey and Miller

• Haldane and Miller

Multiple Choice

How did Miller and Urey tested the hypothesis of Oparin and Haldane?

• By assuming that complex life forms are existing as it is and has no origin.

• By doing a simulation of the conditions of early earth to prove that complex life forms came from the complexity of the earth.

• By doing a simulation of the conditions of early earth to prove that complex life forms came from simple chemical reactions.

Multiple Choice

What organic compound were they able to produce after performing the Miller-Urey experiment?

• Amino acids

• Inorganic compounds

• Bacterias

Manifestation
of 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 Things

Characteristics of

Living 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 of

Living Things

Anabolism (growth and repair)

Catabolism (digestion)

Living things use energy

Metabolism

Plants (geotropism, phototropism)
React/respond to stimuli

Characteristics of

Living Things

Grow and Develop

Reproduce

Characteristics of

Living 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

Open Ended

Using your MLD, search for the organism “water bears” or “tardigrades”.

In 2 minutes, be familiar with the tardigrades, especially about their survival, and answer the following questions:

Are tardigrades living organisms, non-living things, or settling in-between?

Support your answer based from your research of tardigrades.

What are Tardigrades?

These are microorganisms that are considered as extremophiles. They can live in extreme conditions that they can even be left in the outer space and survive!

Thank you for listening!