6. How do we know is something is
‘living’?
All living things are characterised as being able to do seven
things
These are usually remembered by the mnemonic MRS GREN
M
R
S
G
R
E
N
7. Life is organized into different levels
based upon size (from small to large).
8. Organisms and Cells
Some organisms are unicellular.
This means they are made of only one cell.
Examples: bacteria, yeast
Some organisms are multicellular.
This means they are made of many cells.
Examples: humans, trees
9. Organisms and Cells
Unicellular organisms have nothing but a
single cell.
However, multicellular organisms have
many more levels of organization to make
sure the whole body can work correctly,
even when it is doing many things at the
same time.
10. Growth
• Increase in cell size (unicellular) and/or an
increase in cell number (multicellular)
11. Reproduction
• Asexual- cell division (mitosis)—one cell
becomes two Ex: bacteria
• Sexual- union of sex cells (sperm and egg)
Ex: plants and animals
12. Movement
• 3 types:
A. Place to Place- (ex: bear running, bird
flying, etc)
B. External Part- (ex: + phototropism,
plants orient leaves toward sun)
C. Internal- (ex: cytoplasmic streaming)
13. Adaptation
• Changing to meet the needs of the
environment
Examples:
1. Bird migration- behavioral adaptation
14. Adaptation (continued)
2. Human body temperature- Physiological
adaptation
3. Hibernation- physiological adaptation
4. Hare ear length (desert vs. arctic hares)-
structural adaptation
17. Responsiveness
• Reaction(s) to various stimuli
Examples of stimuli: light, heat, pH,
vibration, smell, etc.– earthworms respond
to all of these
18. Branches of Biology
1. Zoology- the study of animals
2. Ichthyology- the study of fish
Why Important? Fish are indicator
species. Alert humans to potential
environmental problems
19. 3. Mammalogy- study of mammals (NASA)
4. Ornithology- the study of birds
Why important? DDT(insecticide used in
‘50s and ’60s) Birds of prey #s declined
bioaccumulation- the build up of chemicals
or toxins in living things
20. 5. Botany- the study of plants
Why important? Food production,
medicines
6. Microbiology- study of small life
Why important?
Medicines, bioterrorism
21. 7. Anatomy- study of an organism’s parts
8. Physiology- study of how organism’s
parts work
Why important? Health professions,
veterinarians
22. 9. Entomology- study of insects
Why important? West Nile virus, Yellow
fever– carried by mosquitoes
10.Genetics- study of heredity and genetic
material (DNA/RNA, chromosomes,
genes)
Why important? Cloning, research,
solving crime
23. 11.Ecology- study of all life in a particular
area, the relationships b/t those life forms
and the environment
Why important? AMD, Overpopulation
Ozone Depletion/Greenhouse Effect
Rainforest Destruction
Pollution- other states pay to dump
garbage in PA
24. 12.Cell Biology- the study of cells
Why Important?
Need to know about cells to learn more
about whole organisms
25. Early Contributions
●Robert Hooke - First person to see cells, he was
looking at cork and noted that he saw "a great many
boxes. (1665)
●Anton van Leeuwenhoek - Observed living cells in
pond water, which he called "animalcules" (1673)
27. The development of the microscope – a brief
history: Robert Hooke’s development of the
compound microscope and examination of cork
tissue.
Watch YouTube Video: Cell Theory (3.30 min)
(https://youtu.be/dscY_2QQbKU)
28. ●Theodore Schwann - zoologist who observed tissues of
animals had cells (1839)
●Mattias Schleiden - botanist, observed tissues of plants
contained cells ( 1845)
●Rudolf Virchow - also reported that every living thing is
made of up vital units, known as cells. He predicted that
cells come from other cells. (1850 )
29. The Cell Theory
1. Every living organism is
made of one or more cells.
2. The cell is the basic unit of
structure and function.
3. All cells arise from pre-
existing cells.
*Why is the Cell Theory
called a Theory and not
a Fact?
