2. What is a Living Being?
All living beings have the following 7 characteristics:
1. Living Beings are Composed of Cells:
• Single-cell or Unicellular organisms have
everything they need to be self-sufficient.
• Multicellular organisms, specialization increases
until some cells do only certain things.
2. Living beings have a chemical composition and are
highly organized. All living beings are composed of
chemical elements, the most popular being:
C, H, N, O, P, S – which are called the primary
bioelements.
3. • The primary bioelements are organized to form
biomolecules, which can be classified as organic
(containing C) or inorganic (no C). Biomolecules
are organized to form organelles within a cell.
4. Living beings must be able to organize simple
substances into complex ones. Living beings
organize cells at several levels:
– Cells – the smallest form of life
– Tissue - a group of cells that perform a
common function.
– Organ - a group of tissues that perform a
common function.
– Organ system - a group of organs that
perform a common function.
– Organism - any complete living thing.
5.
6.
7. •3. Living Things Use Energy
Living things take in energy and use it for
maintenance and growth. Autotrophs or
Heterotrophs.
Autotroph is an organism which
uses simple inorganic molecules
and energy from the sun to produce
organic molecules
Heterotroph is an organism which
uses organic molecules for growth
8. 4. Living Things Respond To Their Environment
- Living things will
make changes in
response to a
stimulus in their
environment.
Mimosa pudica
http://www.youtube.com/watch?v=g0LFBM3hOLs
5. Living Things Grow
• Cell division - the orderly formation of new cells.
• Cell enlargement - the increase of mass. Cells grow
to a certain size and then divide.
• An organism gets larger as the number of its cells
increases.
9. 6. Living Things Reproduce
• Reproduction is not essential for the survival of individual
organisms, but must occur for a species to survive.
• All living things reproduce in one of the following ways:
• Asexual reproduction - Producing offspring without the use
of gametes.
• Sexual reproduction - Producing offspring by the joining of
sex cells.
7. Living Things Adapt To Their Environment
• Adaptations are traits giving an organism an advantage in a
certain environment.
• Variation of individuals is important for a healthy species.
10. Questions:
1. Do all living things have all of the
characteristics of life? If your answer is no,
give an example.
2. Name some non-living thing that uses
energy.
3. Name some non-living thing that grows.
11. What is a cell?
It took a long time for people to discover cells
and to figure out what they were. Most cells are
microscopic, meaning that we need to use a
microscope to see them. Everything we know
about cells is called “cell theory”.
12. History of Cell
Theory
The word cell (from the
Latin word for chamber,
cello) wasn’t used as a
biological term until 1665.
That’s when Robert
Hooke, an English
scientist, looked at a thin
slice of a cork plant under
a compound
microscope he had built
himself. Hooke noticed
small holes surrounded by
walls and named these
tiny pores cells.
13. History of Cell Theory
Antonie Philips van Leeuwenhoek
(the father of microbiology) was a
Dutch scientist who is credited to
have been the first person to
observe microscopic observations
of live cells. In 1674, Van
Leeuwenhoek observed muscle
and blood cells, and many
microogranisms through
microscopes he had built himself.
14. History of Cell Theory
In 1839, German scientists
Theodor Schwann stated
that all animals are made up
of different kinds of cells and
Mattias Jakob Schleiden
stated that all plants are
made up of different kinds of
cells. Schwann and
Schleiden stated that cells
are the basic units of life
and that all living beings
are made of cells.
But where did cells
come from?
15. History of Cell Theory
In 1855 the German
scientist Rudolph
Virchow stated
that every cell
originates from
another existing
cell. Virchow
demonstrated the
first evidence of
cell division.
16. History of Cell Theory
Eventhough cell
theory was
becoming popular
among the
scientific
community in the
19th century
people still
believed of
spontaneous
creation of cells
through non-living
17. Cell Theory says that….
2. All living things or organisms are made
of cells.
4. New cells are created by old cells
dividing into two.
6. Cells are the basic building units of life.
18. Discussion Question
• Make a timeline of the scientific
discoveries leading to cell theory
• State the three postulates of cell theory
21. There are two types of cells:
Prokaryotic Cells
and
Eukaryotic Cells
22. These are two distinct types of cells with
STRUCTURAL differences.
Prokaryotes Eukaryotes
Archaea Animal Plant
Bacteria
23.
24. The Six Kingdoms:
Plants, Animals, Protists, Fungi, Archaebacteria, Eubacteria.
In the previous slide we saw 3 kingdoms. In the
classification of living things we have 6 kingdoms.
25. The identification and classification
of living beings is called taxonomy.
Discussion of taxonomy began with
Aristotle but it was popularized by
the Swedish scientist, Carolus
Linnaeus in the 18th century.
Linneus classified all living things
into two kingdoms: Plantea and
Animalia. Linnaeus also began
binomial nominclature; a two
named naming system.
ex.: Humans = Homo sapiens
We now classify things first with
their domains; Archea, Bacteria,
Eukarya. Domains are later divided
into kingdoms, then phylums, and
so on
26.
27. Prokaryote Cell
A single celled
organism that does
not have a nucleus.
Add this to your vocabulary book
28. Traits of Prokaryotes:
(pro-care-ee-ohts)
2. They do not have a nucleus, and their
genetic material is not stored in the nucleus.
4. They have some organelles, but not many.
3. They are less complicated that eukaryotes.
8. Prokaryotes are found in the
domains of Eubacteria and
Archaea.
29. Bacteria may be small but they are powerful!
During the 14th century, 25% of Europe was killed
by a bacteria (Yersinia pestis) called the
Bubonic Plague, also called Black Death. This
bacteria was spread to humans through fleas
and rodents.
30. But at the same time we need
bacteria to live!
1. Bacteria are decomposers and without them all
other organisms would not be able to survive.
2. We use bacteria in our digestive system to
help digest our food. There are approximately
ten times as many bacterial cells as human
cells in the human body!
3. We could not make cheese or yogurt without
bacteria.
31. Eukaryote Cell
A more complex cell
with a nucleus and
many organelles.
Add this to your vocabulary book
32. Traits of Eukaryotes:
(you-care-ee-othts)
1. They all have a nucleus where the
genetic material of the cell is stored.
2. They have many organelles that
work together to help the cell
function.
33.
34. More traits of Eukaryotes:
(you-care-ee-othts)
1. Eukaryotic cells are much more complex than
prokaryotic cells.
3. They can be just one cell or can make up more
complex multi-cellular organisms.
6. All plants, animals, fungi, and protists are
eukaryotic cells.
35. Think – Pair - Share
What do you think is
the main difference
between a prokaryotic
cell and a eukaryotic
cell?
36. The nucleus!
Prokaryotic cells do not have a
nucleus and eukaryotic cells
do have a nucleus. This
allows eukaryotic cells to make
multicellular organisms and
perform more complex
functions.
