Photosynthesis Respiration Cell division Cell Processes Photosynthesis Respiration Cell division

Autotrophs-also known as producers, they are green plants that can make their own food Heterotrophs-also known as consumers, have to eat food

Chemical energy-all cells are fueled by a chemical energy called ATP Chemical energy-all cells are fueled by a chemical energy called ATP. It is a result of breaking down sugar in cells. adenine ribose phosphates

Photosynthesis: The process of using sunlight energy to make a chemical energy The overall equation: 6CO2 + 6H2O --> C6H12O6 +6O2 (it actually occurs in series of smaller steps) oxygen

Properties of light: White light is a mixture of colors-each color has a different wavelength and a different amount of energy. It can be broken down into its separate colors with a prism.

Rainbows separate the. colors of light in the. same way. Light goes Rainbows separate the colors of light in the same way. Light goes through the drop of water and gets bent

Pigments-substances that absorb or reflect light

Plant pigments: 1. Chlorophyll-reflects green, chlorophyll a is light green and chlorophyll b is dark green 2. Xanthophyll-reflects yellow 3. Carotenes-reflects oranges 4. Anthocyanins-reflects red

Steps in photosynthesis: 1. The light dependent reaction-sunlight is absorbed by the pigments in the chloroplast. This energy is used to split water. The oxygen from the water is given off.

The remaining Hydrogen is also separated into protons and electrons The remaining Hydrogen is also separated into protons and electrons. The electrons and protons continue on to separate reactions where some ATP will be made that will provide the energy to build a sugar molecule. glucose model

2. The next step is called the Calvin cycle (or sometimes the dark reaction because no light is required.) CO2 from the air enters the leaf. In a series of reactions the CO2 is used to form a sugar molecule.

Respiration Is the process of releasing the energy in sugar by breaking the bonds holding it together. In a series of reactions ATP is formed. This is how we create energy for all life processes. The overall equation: C6H12O6 + 6O2 --> 6CO2 + 6H2O + energy (ATP)

It is similar to how a car works:

Steps in cellular respiration: 1. Respiration begins with a step called glycolysis. One sugar molecule is broken in half making two 3 carbon molecules. From this 2 ATP are made. +2 ATP

Now cells make a choice between step 2 and step 3: 2. If no oxygen is present the next step will be fermentation. The two 3 carbon molecules are broken down to individual carbons. A process without oxygen is called anaerobic. examples:

examples: a. Alcoholic fermentation is done by yeast. It makes alcohol and carbon dioxide. this is used by the bread and alcohol industries

b. Lactic acid fermentation is done by muscle cells b. Lactic acid fermentation is done by muscle cells. It makes lactic acid and carbon dioxide. Lactic acid is toxic and makes muscles hurt.

3. If oxygen is present (called aerobic) then a process called the Kreb’s cycle occurs instead. The two 3 carbon molecules go through a series of steps of breaking down and recombining until carbon dioxide is released as waste. 34 additional ATP are made in aerobic respiration.

https://www.youtube.com/watch?v=eo5XndJ az-Y

Cell growth Cells reach a certain size and then they must divide. Reasons: 1. DNA overload. The amount of DNA does not increase as the cell grows.

2. Material exchange. Materials are used up faster than they can be replaced in a large cell. -Surface area is the amount of cell membrane. -Volume is the amount of material inside the membrane. -Volume increases faster than surface area as a cell grows.

The solution is cell division The solution is cell division. Since smaller cells are more efficient than bigger cells, the cell will divide and form smaller cells. Each division fixes the surface area to volume ratio.

Rates of cell growth Cell division is controlled. Not all cells divide at the same rate. -Skin and bone cells divide many times throughout our lives -Muscle and nerve cells do not divide after they are formed -Chemicals called cyclins regulate when cells can divide

Factors that determine if a cell will divide: 1. Space-normal cells in a lab experiment grow until they touch each other or the side of the dish. 2. Injuries-cells at an injury site are stimulated to divide rapidly so that healing will occur.

Uncontrolled cell division-cancer -cells have lost their ability to control cell division. Cancer cells form masses of cells called tumors. -cancer cells do not care about touching each other but will grow until all food is gone

Chromosomes are condensed, coiled pieces of DNA. They will take into the new cell all the genetic information.

Chromosomes must double in number before cell division.

Humans have 46 chromosomes.

Cell division occurs in 2 stages: -Mitosis is the division of the nucleus. -Cytokinesis is the division of the cytoplasm.

The cell cycle is the period from one division to the next.

Interphase is the time a cell spends between cell divisions It is divided into 3 stages: G1- the cell is growing S- the DNA copies itself G2- the rest of the cell prepares to divide

The stages of mitosis: Prophase-longest stage The chromosomes are now visible. 2 centrioles separate and begin to move to opposite sides of the cell. A spindle of microtubules forms between them.

Metaphase-shortest stage chromosomes line up along center of cell (called the equator) the chromosomes attach to the spindle threads at their centromere

Anaphase- the 2 halves of the chromosome pull apart from each other and move along the threads to opposite sides of the cell.

Telophase- chromosomes form 2 new nuclei the DNA lengthens and disappears from view.

Cytokinesis: the cell begins to lengthen in anaphase and splits completely after telophase. -Animal cells form a cleavage furrow -Plant cells form a cell plate which becomes a cell wall between them.

The new cells begin interphase and the cell cycle starts all over again. Mitosis is asexual reproduction. All cells will be identical. It is used for growth and repair in the body.

Lab-mitosis in onion cells

Picture sources http://www.drbrodie.com/images/green_leaf.jpg http://www.sthelena.com/aspen%20yellow%20leaf.JPG http://www.oc-illnesses-and-creativity.net/Red%20leaf..gif http://www.micro.utexas.edu/courses/levin/bio304/genetics/chromosome.gif http://biology.clc.uc.edu/graphics/bio104/cellresp.jpg http://www.eurotec.co.jp/007rollfit/images/pigments.jpg http://www.cancerguide.org/shasta/chromosomes.jpg