Biology
What is Biology?
• It is the science of LIFE.
• Which includes: living organisms,
including their structure, function, growth,
origin, evolution, and distribution.
Why study Biology?
• We can learn more about our natural
environment and how our bodies work,
say for instance you realize that your
body behaves in an weird way you may
even know why it could be doing that
Introduction to BIOLOGY-LIFE
• How do we define LIFE?
We say that activities carried out by living
organisms are the characteristics of life.
What are the CHARACTERISTICS of LIFE
Those include…
1. Cells
2. Nutrition
3. Respiration
4. Excretion
5. Homeostasis
6. Growth and Development
7. Movement
8. Reproduction
9. Sensitivity
10. Adaptability
The major topic I will be talking about is…
CELLS
CELLS
• ALL organisms are made of simple units called
cells.
• Cells carry out activities necessary for the
organism to stay alive.
• In the body, there are brain cells, skin cells, liver
cells, stomach cells, and the list goes on. All of
these cells have unique functions and features.
And all have some recognizable similarities. (E.g.
all have nucleus…etc)
A Specific view of the CELL
Basic Recap-CELL
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CELL
Cell Membrane
Cytoplasm
Nucleus
Nucleus
- Large Oval body near the centre of the cell.
- The control centre for all activity.
- Surrounded by a nuclear membrane.
Nucleoplasm
- is the protoplasm in the nucleus.
- contains genetic material ---> CHROMOSOMES
(DNA)
Nucleolus
- is found in the nucleus.
- contains more genetic information (RNA)
Cell Membrane
- the outer boundary of the cell.
- it separates the cell from other cells.
- it is porous ---> allows molecules to pass through.
Cell Membrane
Cell Wall ( Plant Cells Only )
- non living structure that surrounds the plant cell.
- protects + supports the cell.
- made up of a tough fibre called cellulose.
Cell Wall
Cytoplasm
- cell material outside the nucleus but within the cell
membrane.
- clear thick fluid.
- contains structures called organelles.
Vacuoles
- are clear fluid sacs that act as storage areas for
food, minerals, and waste.
- in plant cell the vacuoles are large and mostly filled
with water. This gives the plant support.
- in animal cells the vacuoles are much smaller.
Vacuoles
Mitochondria
- power house of the cell.
- centre of respiration of the cell.
- they release energy for cell functions.
Chloroplasts ( Plant cells only )
- contains a green pigment known as chlorophyll
which is important for photosynthesis.
Ribosomes
- tiny spherical bodies that help make proteins.
- found in the cytoplasm or attached to the
endoplasmic reticulum.
Endo Plasmic Reticulum ( ER )
- systems of membranes throughout the cyto plasm.
- it connects the nuclear membrane to the cell
membrane.
- passageway for material moving though the cell.
Golgi Bodies
- tube like structures that have tiny sacs at their
ends.
- they help package protein.
Lysosomes
- " suicide sacs "
- small structures that contain enzymes which are
used in digestion.
- if a lysosome were to burst it could destroy the
cell.
References
• http://wiki.answers.com/Q/Why_study_biology
• http://en.wikipedia.org/wiki/Biology
• http://i77.photobucket.com/albums/j48/annahybrid
/cell-diagram.jpg
• Google Images
• http://jgimp.tripod.com/cells.html