1-1 Themes of Biology

1
1-1 Themes of Biology

• Six unifying themes
• How energy is acquired
• Compare/contrast living vs. non-living things

2
BIOLOGY

• Biology science of life is the study of ALL
  living things from unicellular organisms (too
  small to see with the naked eye) to interactions
  among millions of organisms.

3
BIOLOGY

• 40 million species inhabit the Earth but only 2
  million have been identified
• First organism was probably unicellular and about
  3.5 billion years ago. These lasted for millions
  of years alone. Then over time, we have what we
  see today

4
6 Major Biological Themes (ICHORE)

• 1. Cell structure and function
• 2. stability and Homeostasis
• 3. Reproduction and inheritance
•  

• 4. Evolution
• 5. Interdependence of organisms
• 6.matter, energy and Organization

5
Cell Structure and Function

• Cell-basic unit of life. All organisms are made
  of cells. Unicellular is 1 cell and multicellular
  is more than 1 cell. Cells have different
  functions. Cells are small but highly organized
  and they contain information to carry on lifes
  processes.

• Surrounded by membrane. Inside cell is set of
  instructions (genetic material) necessary to make
  new cells.
• Unicellular organisms produce exact organisms.
  Multicellular organisms go through cell
  differentiation to produce new cells, which are
  different.

6
Stability and Homeostasis

• Stable level of internal conditions is
  homeostasis. Found in all living things. Human
  body temperature is 98.60 F or 370 C.

7
Reproduction and Inheritance

• Reproduction is to produce new organisms like
  themselves. Hereditary information is passed on.
  This is in the form of a large molecule called
  deoxyribonucleic acid (DNA). DNA in 1 human would
  extend several feet. Humans have 50 trillion
  cells.

8
Reproduction and Inheritance

• A short segment of DNA that contains instructions
  for development of a single trait is called a
  gene.

• sexual reproduction combining hereditary
  information from two organisms of same species to
  form 1 new offspring that contains the hereditary
  information of both. EX. Sperm with egg

9
Reproduction and Inheritance

• Asexual reproduction hereditary
  information from different organisms is not
  combined. 1 cell gives rise to 2 cells with exact
  identical copy of hereditary information. EX.
  Bacteria and single cell algae.

10
Evolution

• To change over generations
• Natural selection is the driving force in
  evolution. Those, which have the best traits, are
  better able to reproduce and pass these traits on

11
Interdependence of Organisms

• Ecology is the study of interactions of organisms
  with one another and their environment. Small
  ecosystems (a spider and its web) to a large
  ecosystem (the rain forest).

12
Interdependence of Organisms

• The rain forest has fragile topsoil but very
  stable environments. Humans are destroying the
  rain forest. They cut and burn the trees, they
  build roads, and they use it for farmland. This
  all causes plants and animals to become extinct,
  it depletes the topsoil of minerals and causes it
  to dry up and harden under the heat of the sun
  and oxygen is replaced by carbon dioxide.

• Use to be 6 million square miles in the 90s but
  55,000 square miles are destroyed each year. At
  this rate, the rain forest could be gone in 100
  years.

13
Interdependence of Organisms

• Products from the rain forest include rubber,
  coffee, fruits and nuts, wood for furniture (teak
  and mahogany), wood for paper.

14
Matter, Energy and Organization

• All living things need a constant supply of
  energy.
• Photosynthesis is light to put together. To
  capture energy from the sun and change it to a
  usable source

15
Autotrophs

• Organisms that obtain energy by making their own
  food.
• EX. Plants convert water and carbon dioxide
  into sugars and starches.

16
Heterotrophs

•  Organisms that must take in food to make their
  energy.
• EX. All animals, some fungi and many unicellular
  organisms.
• Must consume autotrophs or other heterotrophs

17
Living vs. Non-living

• Living things, even the smallest (algae) are more
  advanced than non-living things (salt crystals,
  rock crystals)
•  
• Living things have greater organization, greater
  stability, greater growth, more energy use and
  better reproduction.