What is Life?

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What is Biology?
What is Life?
All this creates a Question:
What
is
Life?
Characteristics of Life
• All life has seven characteristics in
common:
– Living things are made of cells.
Cells
– All living things are made of one or more
cells.
– A cell is the smallest unit capable of all life
processes
Characteristics of Life
• All life has seven characteristics in
common:
– Living things are made of cells.
– Living things maintain their internal
environment.
Homeostasis
– All living organisms must maintain a stable
internal environment in order to function
properly.
– The maintenance of a stable internal
environment in spite of changes in the
external environment is called
homeostasis.
Characteristics of Life
• All life has seven characteristics in
common:
– Living things are made of cells.
– Living things maintain their internal
environment.
– Living things pass on their traits.
Heredity & Evolution
– When an organism reproduces, it passes
on its own traits to its offspring in a process
called heredity.
– Inherited characteristics change over
generations. This process is called
evolution
Characteristics of Life
• All life has seven characteristics in
common:
– Living things are made of cells.
– Living things maintain their internal
environment.
– Living things pass on their traits.
– Living things perform chemical activities.
This is known as metabolism.
Metabolism
– Living organisms carry out different chemical
reactions in order to obtain energy.
– The sum of all the chemical reactions carried out
in an organism is called metabolism.
– Almost all of the energy used by living things
originally comes from the sun.
Characteristics of Life
• All life has seven characteristics in
common:
– Living things are made of cells.
– Living things maintain their internal
environment.
– Living things pass on their traits.
– Living things perform chemical activities.
This is known as metabolism.
– Living things grow and develop.
Growth and Development
– All living organisms grow.
– As organisms grow, many change. This
process is called development.
– Development differs from evolution
because development refers to change
in a single individual during that
individual’s life.
Characteristics of Life
• All life has seven characteristics in
common:
– Living things are made of cells.
– Living things maintain their internal
environment.
– Living things pass on their traits.
– Living things perform chemical activities.
This is known as metabolism.
– Living things grow and develop.
– Living things respond to a stimulus.
Response to Stimuli
– In addition to maintaining a stable internal
environment, living organisms respond to
their external environment.
– Can you think of a way that you have
responded to your environment
today?
Characteristics of Life
• All life has seven characteristics in
common:
– Living things are made of cells.
– Living things maintain their internal
environment.
– Living things pass on their traits.
– Living things perform chemical activities.
This is known as metabolism.
– Living things grow and develop.
– Living things respond to a stimulus.
– Living things reproduce.
Reproduction
• Most living things can reproduce. Reproduction
is the process by which organisms make more of
their own kind from one generation to the next.
The Cell Theory
1. All living things are composed of cells.
2. Cells are the basic units of structure and
function in living things.
3. New cells are produced from existing
cells.
Cells Timeline
• Robert Hooke (1665): studied
•
•
•
•
Go to
Section:
cork; saw tiny, regular shaped
“boxes”; called them cells.
Matthais Schleiden (1838)
• All plants are made of cells
Theodor Schwann (1839)
• All animals are made of cells
Rudolf Virchow (1855)
Concluded all cells come from
other cells
•What is a VIRUS??
•Is it ALIVE????
Slide # 4
Viruses are 1/1000 to 1/10,000
the size of our cells.
Slide # 5
What is a Virus?
Classified as non-living:
1. are not made up of
cells
2. Cannot live
independently
3. can not reproduce on
their own
4. Does not require
food/does not grow,
develop or move
Slide # 7
Viruses consist of:
1.Nucleic acid: DNA
or RNA (inner
core)
Capsid
2.Protein Coat,
called a Capsid
Cold virus
Tobacco
Mosaic Virus
Flu virus
Bacteriophage virus
Notes: Cells
http://www.studiodaily.com/main/technique/tprojects/6850.html
The Cell Theory
1. All living things are composed of cells.
2. Cells are the basic units of structure and
function in living things.
3. New cells are produced from existing
cells.
Cells Timeline
• Robert Hooke (1665):
•
•
•
•
Go to
Section:
studied cork; saw tiny, regular
shaped “boxes”; called them
cells.
Matthais Schleiden (1838)
• All plants are made of cells
Theodor Schwann (1839)
• All animals are made of cells
Rudolf Virchow (1855)
Concluded all cells come from
other cells
Cell Types
There are two categories of cells:
1. Eukaryotic –
Have a nucleus
and membrane
bound organelles
Examples include
plants, animals,
fungi, and
protists.
Cell Types
There are two categories of cells:
2. Prokaryotic – Have
no nucleus and no
membrane bound
organelles
Bacteria are an
example.
Make a Venn Diagram like
shown below:
Prokaryotic vs. Eukaryotic Cells
Two specific organelles
have made Eukaryotic cells
be the most successful….
• Mitochondria
– Consumes O2 to make
energy (ATP) from
sugar (food)
• Chloroplast
– Consumes H2O and
CO2 as it takes in
energy from the sun to
make sugar (food)
But guess what….
• These two organelles (mitochondria and
chloroplast) are thought once be their own
prokaryotic cell living inside a larger host
cell…….these “prokaryotes” provided
nutrients/oxygen to the host and in turn got
a safe place to live.
ENDOSYMBIOTIC
THEORY
Since BOTH these organelles have
their OWN DNA even more support
that they…..
• Chloroplast have DNA
• Mitochondria have DNA
Endosymbiotic theory for
dummies…..
• https://www.youtube.com/watch?v=FQmAnmLZtE (mr. Anderson teacher
talking with pictures)
Two types of Eukaryotic
cells are:
• PLANT Cells
• ANIMAL Cells
Make a Venn Diagram like
shown below:
Organelles in Plant vs. Animal Cells
Animal Cells:
1. Lysosomes
2. Vacuoles are much
smaller
Plant Cells:
1. Chloroplasts
2. Cell wall
3. Vacuoles are much larger
Plant Cells
Cell Wall
Nucleus
Chloroplast
Characteristics of Plant Cells:
1. Rectangular or square shape
2. Cell wall that is composed
mostly of cellulose
Animal Cells
Notice the circular shape of animal
cells. Not all animals cells have this
shape, but it is more common than
not.
Nucleus
Cell membrane
Organelles
• Organelles - Specialized structures in a
cell that have a specific function.
Cell Membrane
• Cell Membrane - Thin, flexible barrier
around a cell; regulates what enters and
leaves the cell (selectively permeable)
Prokaryote
Eukaryote
Plant
Animal
Cell Wall
• Cell Wall - Strong supporting layer around the
cell membrane in plants, algae, and some
bacteria that
supports and
shapes
– Made of CELLULOSE
in plants,chitin,
etc. depending
on the
organism.
Prokaryote
Eukaryote
Plant
Nucleus
• Nucleus – Contains DNA (genetic
information) and instructions for the
productions of proteins and other cellular
processes
– Bounded by
the nuclear
envelope
Eukaryote
Plant
Animal
Nuclear Envelope
• Nuclear Envelope –
Layer surrounding the
nucleus of a cell covered
in nuclear pores, which
allow material to move
into and out of nucleus
Vacuoles
• Vacuoles – Sac like structure that
stores water, salts, proteins, and
carbohydrates.
– Plants contain large central vacuoles
– Animals contain many smaller vacuoles
Eukaryote
Plant
Animal
Ribosomes
• Ribosomes – small
particles of rRNA;
• Where proteins are
assembled
– Found throughout
the cytoplasm and
on the
rough ER.
Prokaryote
Eukaryote
Plant
Animal
Endoplasmic Reticulum
• Endoplasmic Reticulum (ER) - Internal
membrane system in cells in which lipid
components of the cell membrane are
assembled and some proteins are
modified
Rough Endoplasmic
Reticulum
• Rough ER- The portion of the ER involved
in the synthesis of proteins
– Given this name
because of the
ribosomes found
on its surface.
– Abundant in cells
that produce
large amounts
of protein for
export.
Eukaryote
Plant
Animal
•
Smooth Endoplasmic
Reticulum
Smooth ER – Endoplasmic reticulum where
ribosomes are not found on its surface
– Involved in:
1. synthesis of
lipids for cell
membranes
1. detoxification
of drugs (in
liver cells)
Eukaryote
Plant
Animal
Golgi Apparatus
• Golgi Apparatus - Modify, sort, and
package proteins (from the ER) into vesicles
for storage in the cell or secretion outside
the cell.
– Finishing
touches are
put on proteins
before they
are ready to
leave the
“factory.”
Eukaryote
Plant
Animal
Cytoskeleton
• Cytoskeleton - Internal
structure of some cells
that gives shape and is
involved in movement
• Consists of
1. Microtubules- hollow
and tube like; made of
proteins called tubulins
2. Microfilaments- thin,
thread like; made of
protein called actin.
Eukaryote
Plant
Animal
Chloroplasts
• Chloroplasts Organelles that capture
the energy from sunlight
and convert it into
chemical energy in food
(photosynthesis).
– Like a solar power plant.
– Contain the green
pigment chlorophyll.
Eukaryote
Plant
Mitochondria
• Mitochondria - Organelles
that convert the chemical
energy stored in food
(glucose) to make energy
molecules for cells
Eukaryote
Plant
Animal
Lysosomes
• Lysosomes – Vesicles from a Golgi that
contain digestive enzymes that
1. Digest/break down lipids, carbohydrates,
and proteins into small molecules that
can be used by the cell
2. Break down/get rid of
waste or worn out cell
parts
Eukaryote
Animal
Centrioles
• Centrioles - Paired
structures located in
the cytoplasm of
animal cells near the
nucleus give rise to
the spindle during cell
division.
Eukaryote
Animal
Cytoplasm
Prokaryote
Eukaryote
Plant
Animal
• Cytoplasm – The fluid matrix that consists
of water and dissolved substances such
as proteins and nutrients. (cytosol)
Cilia and Flagella
• Cilia are short,
numerous, and
hair-like
• Flagella are
long, fewer,
and tail-like
• Both are for
movement
Prokaryote
Eukaryote
Animal
Review:
• A bacteria is a Prokaryotic or Eukaryotic
cell?
• A protist is a Prokaryotic or Eukaryotic
cell?
• A plant is a Prokaryotic or Eukaryotic cell?
• DNA is found in both Prokaryotic and
Eukaryotic cells. True or False
Review:
• A bacteria is a Prokaryotic or Eukaryotic
cell?
• A protist is a Prokaryotic or Eukaryotic
cell?
• A plant is a Prokaryotic or Eukaryotic cell?
• DNA is found in both Prokaryotic and
Eukaryotic cells. True or False
Review:
• A bacteria is a Prokaryotic or Eukaryotic
cell?
• A protist is a Prokaryotic or Eukaryotic
cell?
• A plant is a Prokaryotic or Eukaryotic cell?
• DNA is found in both Prokaryotic and
Eukaryotic cells. True or False
Review:
• A bacteria is a Prokaryotic or Eukaryotic
cell?
• A protist is a Prokaryotic or Eukaryotic
cell?
• A plant is a Prokaryotic or Eukaryotic cell?
• DNA is found in both Prokaryotic and
Eukaryotic cells. True or False
Review:
• DNA is found in both Prokaryotic and
Eukaryotic cells. True or False
• They both have DNA, except eukaryotes
have it located in a membrane bound
nucleus instead of thrown into the
cytoplasm.
What is the organelle labeled #9?
What is the organelle labeled #9?
MITOCHONDRIA
What is the organelle labeled #5?
What is the organelle labeled #5?
ROUGH ENDOPLASMIC
RETICULUM
What is the organelle labeled #6?
What is the organelle labeled #6?
GOLGI APPARATUS
VACUOLE
What is the
organelle
labeled #14?
What is the
organelle
labeled #14?
CHLOROPLAS
T
What is the
organelle
labeled # 2?
What is the
organelle
labeled # 2?
VACUOLE
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