1. Basic Biological Principles
Characteristics of Life, Cells, Organization of Life

2. 7 Characteristics of Life
Living things MUST exhibit these 7 characteristics to be considered living:
Order
Metabolism
Response to a Stimulus
Reproduction
Homeostasis
Growth and Development
Evolutionary Adaptation

3. 7 Characteristics of Life
Order
Organized arrangement of parts in a living thing or group of living things
Smallest to largest
Atom
Molecules
Cell
Tissue
Organ
Organ system
Organism
Single-celled organisms stop at the cell level and most multi-celled organisms exhibit all levels

4. Figure 1.4B Some important properties of life.
(1) Order

5. 7 Characteristics of Life
Metabolism
All of the chemical reactions that take place in an organism
Chemical reactions either break down molecules or build up molecules in the body
Organisms must be able to perform chemical reactions

6. Figure 1.4B Some important properties of life.
(4) Energy processing

7. 7 Characteristics of Life
Response to a Stimulus
Must be able to react to the environment
Running away from a prey or a plant growing towards light
Reproduction
Produce more of your own kind
Asexual-only ONE parent and make a genetically identical clone to the parent
Sexual-usually more than one parent and make genetically different offspring from the parents

8. (5) Response to the environment
Figure 1.4B Some important properties of life.
(5) Response to the environment

9. Figure 1.4B Some important properties of life.
(6) Reproduction

10. 7 Characteristics of Life
Homeostasis
Maintain stable internal conditions
Temperature, water, salts, gases and even cell number
If our temperature increases, humans sweat
If water levels drop too low, we get thirsty and our kidneys save water
Growth and development
Increase in size and mature/change from embryo to adult

11. Figure 1.4B Some important properties of life.
(2) Regulation

12. (3) Growth and development
Figure 1.4B Some important properties of life.
(3) Growth and development

13. 7 Characteristics of Life
Evolutionary Adaptation
Ability of an entire species to change genetically over generations to survive in a changing environment
Species that do not adapt will become extinct

14. (7) Evolutionary adaptation
Figure 1.4B Some important properties of life.
(7) Evolutionary adaptation

15. Cells
Cells
Basic unit of structure and function in a living thing (first level where life appears)
Two types of cells:
Prokaryotic cells-cells that do NOT have a nucleus or membrane-bound organelles
Eukaryotic cells-cells that HAVE a nucleus and membrane-bound organelles

16. Cells Cell Size Cells are small to be efficient
Being small allows them to maximize their ability to exchange nutrients and waste with the environment
Cells can become larger by:
Increasing surface area (flat shape and folds in membranes)
Dividing up labor
Prokaryotic cells remain small to maintain efficiency
Eukaryotic cells can be larger because labor is divided into compartments

17. Cells
Similarities between prokaryotic and eukaryotic cells (every cell has these structures):
Cell membranes
Genetic material (DNA)
Ribosomes
Cytoplasm

18. Differences between Prokaryotic and Eukaryotic Cells
Prokaryotic Cells
Eukaryotic Cells
No nucleus
No membrane-bound organelles
Smaller in size
Circular chromosomes
Nucleus
Membrane-bound organelles
Larger in size
Linear chromosomes

19. Prokaryotic cell Eukaryotic cell DNA (no nucleus) Membrane Nucleus
Figure 1.3 Contrasting the size and complexity of prokaryotic and eukaryotic cells.
This figure indicates that the eukaryotic cell is subdivided into functional compartments (organelles) by membranes.
Nucleus
(contains DNA)
Organelles

20. Prokaryotic Cell Structure
External Structures
Pili
Flagellum
Capsule
Cell wall
Cell membrane
Internal Structures
Ribosome
Cytoplasm
Nucleiod
Plasmid
Chromosome

21. Pili Nucleoid Ribosomes Plasma membrane Bacterial chromosome Cell wall
Capsule
Figure 4.3 A structural diagram of a typical prokaryotic cell.
Module 4.3 mentions how antibiotics can specifically target prokaryotic but not eukaryotic cells. This might be a good time to discuss the evolution of antibiotic resistance. Teaching tips and ideas for related lessons can be found at
Flagella

22. Eukaryotic Cell Structure (found in both plant and animal cells)
Flagellum
Cilia
Cell (plasma) membrane
Cytoskeleton
Nucleus
Nucleolus
Endoplasmic reticulum
Golgi apparatus
Lysosome
Mitochondrion
Centrosome
Food vacuole
Vesicle

23. NUCLEUS: Nuclear envelope Chromosomes Smooth endoplasmic reticulum
Nucleolus
Rough
endoplasmic
reticulum
Lysosome
Centriole
Ribosomes
Figure 4.4A An animal cell.
Peroxisome
Golgi
apparatus
CYTOSKELETON:
Microtubule
Plasma membrane
Intermediate
filament
Mitochondrion
Microfilament

24. Eukaryotic Cell Structure
Plant cells only
Cell wall
Central vacuole
Chloroplast

25. NUCLEUS: Rough endoplasmic reticulum Nuclear envelope Chromosome
Ribosomes
Nucleolus
Smooth
endoplasmic
reticulum
Golgi
apparatus
CYTOSKELETON:
Central vacuole
Microtubule
Chloroplast
Intermediate
filament
Cell wall
Plasmodesmata
Microfilament
Figure 4.4B A plant cell.
Mitochondrion
Peroxisome
Plasma membrane
Cell wall of
adjacent cell