Integrated Science: Section 1- Biology Characteristics of Life Science and Technology Cells Photosynthesis Genetics

The 7 Characteristics of Life- Think “Go Roger” when attempting to name all 7 characteristics. G- Living organisms grow O- All life must obtain food R- Organisms respond to their environment O- All life relies on obtaining water G- Gas Exchange takes place in all organisms E- An organism must eliminate waste buildup R- Reproduction is necessary for survival of a species.

Science and Technology Science definition- attempting to understand nature Technology definition- Directly using knowledge to solve problems. Science and Technology are linked. Improving our understanding of nature can improve technology. Improving our problem solving skills ultimately leads to advances in the world we live. Not all advances in technology are productive or used in a positive manner.

Scientific Laws and Theories Scientific Laws are descriptions of natural events. Many of these laws are explained through the use of formulas. (i.e. F=MA) Scientific theory is a set of tested ideas explaining events. Theories may be modified as observations of nature change.

Models Scientific Models- physical items or pictures used to represent a process. Examples include diagrams, drawings, charts, graphs, etc.

Intro to Cells Cells are the basic unit of life. Animal Cell= Round shape Plant Cell= Rectangular shaped Cells are the basic unit of life. Cells originate from other living cells. All living things are made of cells

Why are cells so small? Larger cells require materials to travel farther. The additional travel time in a cell results in a buildup of waste. Eventually, the cell is unable to function efficiently enough to survive.

Photosynthesis Nearly all living things obtain energy directly or indirectly from the sun from photosynthesis. Example 1= Autotrophs (Plants)

Photosynthesis Process The combination of sunlight, water, and carbon dioxide create a chemical reaction inside the chloroplasts. Sugar and Oxygen are created from the chemical reaction. The cell uses the sugar for energy, and releases the Oxygen as waste. The Chemical Equation of Photosynthesis

Photosynthesis and its relationship with Heterotrophs A disruption in the food chain affects every level.

Respiration Respiration- Think of it as the opposite of Photosynthesis. The process of cells obtaining energy from sugars. Cells break down the sugar molecules and release the energy they contain.

Fermentation Fermentation is an energy releasing process that does not require oxygen. This is a slow process, and it does not provide as much energy as respiration. 2 types of fermentation include alcoholic fermentation and lactic acid fermentation.

Cell Division The regular sequence of growth and division that cells undergo is called the cell cycle. The cell cycle contains three stages. 1) Interphase is the period before cell division. 2) Mitosis is the stage where the cell’s nucleus divides into two nuclei. 3) Cytokinesis is the final stage of cell division.

Cell Cycle Diagram

Stage 1- Interphase The cell grows to its full size and produces the structures it needs. Next, the cell makes an exact copy of the DNA in the Nucleus. This is called replication. After replication, the cell prepares to divide itself into two new cells.

Stage 2-Mitosis Mitosis is broken into 4 parts- prophase, metaphase, anaphase, and telophase. Prophase forms chromosomes in the nucleus. Metaphase lines the chromosomes up across the center of the cell. Anaphase splits the chromatid and stretches the cell out. Telophase stretches the chromosomes out and forms a new nuclear envelope around each region of chromosomes.

Stage 3- Cytokinesis The cytoplasm in the cell divides, and the organelles are distributed into each of the two new cells. Animal cells- the cell membrane squeezes together around the middle of the cell and divides up the organelles equally. Plant cells- A cell plate forms in the middle of the cell and gradually develops new cell membranes and cell walls.

DNA Structure DNA looks like a twisted ladder. The sides are made of sugar and phosphate molecules, and the rungs are made of Nitrogen and other elements. DNA has 4 kinds of Nitrogen bases- Adenine (A), Thymine (T), Guanine (G), and Cytosine (C). A only pairs with T, and G only pairs with C.

DNA Replication DNA replication begins by unwinding the DNA ladder and separating the molecules. It looks like a zipper unzipping.