Chapter 4 Cell Processes and Energy How does the sun supply living things with the energy they need? What happens during the process of photosynthesis? Section 1: Photosynthesis

Chapter 4 Cell Processes and Energy Sources of Energy Nearly all living things obtain energy either directly or indirectly from the energy of sunlight captured during photosynthesis.

Chapter 4 Cell Processes and Energy Autotroph vs. Heterotroph Autotroph: any organism that makes its own food using the energy of the sunlight captured by photosynthesis Examples: plants, green algae Heterotroph: an organism that can not make its own food, so it must consume another organism for energy Examples: animals, fungi, most bacteria 95% of all living organisms are heterotrophs. Both autotrophs and heterotrophs get their energy from the sun. Autotrophs get their energy DIRECTLY from the sun, while heterotrophs get their energy INDIRECTLY.

Chapter 4 Cell Processes and Energy The Two Stages of Photosynthesis During photosynthesis, plants and some other organisms use energy from the sun to convert carbon dioxide and water into oxygen and sugars.

Chapter 4 Cell Processes and Energy The Photosynthesis Equation

Chapter 4 Cell Processes and Energy Breaking Down the Photosynthesis Equation Products: C 6 H 12 O O 2 CCCCCC OO OO HHHHHH OO OO OOOOOO ________________________ 6 Carbons + 12 Hydrogens + 18 Oxygens Products: C 6 H 12 O O 2 CCCCCC OO OO HHHHHH OO OO OOOOOO ________________________ 6 Carbons + 12 Hydrogens + 18 Oxygens Raw Materials: 6 CO H 2 O COO COO HHO HHO ________________________ 6 Carbons + 12 Hydrogens + 18 Oxygens Raw Materials: 6 CO H 2 O COO COO HHO HHO ________________________ 6 Carbons + 12 Hydrogens + 18 Oxygens

Chapter 4 Cell Processes and Energy End of Section: Photosynthesis

Chapter 4 Cell Processes and Energy What events occur during cellular respiration? What is fermentation? Section 2: Cellular Respiration

Chapter 4 Cell Processes and Energy Two Stages of Cellular Respiration Cellular Respiration: A process where cells break down simple food molecules such as sugar and release the energy they contain.

Chapter 4 Cell Processes and Energy The Cellular Respiration Equation

Chapter 4 Cell Processes and Energy Photosynthesis and Respiration You can think of photosynthesis and cellular respiration as opposite processes.

Chapter 4 Cell Processes and Energy Fermentation Fermentation: A process that provides cells with energy without using oxygen. Alcoholic Fermentation: Occurs in yeast and other one-celled organisms. This is the process used to make yeast turn grape juice into wine. Lactic Acid Fermentation: Occurs in humans and other animals when they exercise and there is a lack of oxygen. This leads the acid taste in your mouth and sore muscles.

Chapter 4 Cell Processes and Energy End of Section: Respiration

Chapter 4 Cell Processes and Energy What events take place during the three states of the cell cycle? How does the structure of DNA help account for the way in which DNA copies itself? Section 3: Cell Division

Chapter 4 Cell Processes and Energy The Cell Cycle Cell Cycle: The regular sequence of growth and division that cells undergo. Made up of 3 stages: Stage 1: Interphase Stage 2: Mitosis Stage 3: Cytokinesis

Chapter 4 Cell Processes and Energy Interphase Cells spend most of their time in this phase. During Interphase, the following 5 events will occur: The cell will perform its “normal” functions and duties. The cell will grow to about twice it's original size. The cell's organelles will make copies of themselves and double in quantity. The cell's DNA will make a copy of itself right before Mitosis begins. Once the DNA is copied, the cell will make structures that it will use to help divide itself.

Chapter 4 Cell Processes and Energy Mitosis During mitosis, the cell’s nucleus divides into two new nuclei. One copy of the DNA is distributed into each of the two daughter cells.

Chapter 4 Cell Processes and Energy Mitosis Four stages in Mitosis: Prophase Metaphase Anaphase Telophase

Chapter 4 Cell Processes and Energy Mitosis: Prophase “Chromatin” winds up into a condensed shape called “chromatid”. Chromatin: unwound DNA Chromatid: wound DNA

Chapter 4 Cell Processes and Energy Mitosis: Prophase The cell gets ready for the “Tug of War” activity that occurs in Mitosis.

Chapter 4 Cell Processes and Energy Mitosis: Prophase The cell gets ready for the “Tug of War” activity that occurs in Mitosis. The pair of centrioles move to opposite sides of the nucleus. Spindle fibers (the “ropes”) form between the centrioles. The nuclear envelope that surrounds the nucleus breaks down.

Chapter 4 Cell Processes and Energy Mitosis: Metaphase The chromatids line up on the equator of the cell.

Chapter 4 Cell Processes and Energy Mitosis: Anaphase The chromatids separate and move to opposite sides of the cell. The cell starts to stretch apart as it gets ready for Cytokinesis.

Chapter 4 Cell Processes and Energy Mitosis: Telophase Chromatids unwind and return to their string-like chromatin shape. 2 new nuclear envelopes form to make 2 new nuclei.

Chapter 4 Cell Processes and Energy Cytokinesis Must finish after Mitosis or else the cell will split into 2 cells before the DNA is evenly divided. The 2 new cells are called “daughter cells”. Each daughter cell is identical to the original parent cell.

Chapter 4 Cell Processes and Energy The Cell Cycle

Chapter 4 Cell Processes and Energy D.N.A. D.N.A. stands for Deoxyribonucleic Acid. D.N.A. is the “instruction manual” or “blueprint” of all living things.

Chapter 4 Cell Processes and Energy D.N.A. A single strand of D.N.A. in each cell is about 6 feet long. Multiplied by all the cells in your body, you have enough D.N.A. to go to the Sun and back about 70 times (the Sun is 93 million miles away).

Chapter 4 Cell Processes and Energy D.N.A. D.N.A.'s unique shape was discovered by James Watson and Francis Crick in 1953, with help from Maurice Wilkins and Rosalind Franklin.

Chapter 4 Cell Processes and Energy D.N.A. D.N.A. has a double helix structure, which resembles a spiral staircase.

Chapter 4 Cell Processes and Energy D.N.A. The sides of the twisted D.N.A. ladder are made up of a sugar called deoxyribose. In between the deoxyribose sugars is a molecule called phosphate.

Chapter 4 Cell Processes and Energy D.N.A. The rungs (steps) of the D.N.A. ladder is where we find the “blueprint” information. These rungs are made up of only 4 types of nitrogen bases: Thymine (T) Adenine (A) Guanine (G) Cytosine (C)

Chapter 4 Cell Processes and Energy D.N.A. Each rung of the D.N.A. ladder is made up of a pair of nitrogen bases. Adenine (A) only pairs up with Thymine (T). Guanine (G) only pairs up with Cytosine (C).

Chapter 4 Cell Processes and Energy D.N.A. D.N.A. is able to make copies of itself by “unzipping” and filling in the blanks with matching bases.

Chapter 4 Cell Processes and Energy Structure of DNA The DNA molecule, supported by proteins, is shaped like a twisted ladder.

Chapter 4 Cell Processes and Energy Replication of DNA Because of the way in which the nitrogen bases pair with one another, the order of the bases in each new DNA molecule exactly matches the order in the original DNA molecule.

Chapter 4 Cell Processes and Energy End of Section: Cell Division

Chapter 4 Cell Processes and Energy What is differentiation? What factors influence how and when cells differentiate within different organisms? Section 4: Cell Differentiation

Chapter 4 Cell Processes and Energy Specialized Cells Plants have undifferentiated cells in their stems and roots that can give rise to different kinds of cells. Undifferentiated plant cell Leaf cell Transport cell Root cell

Chapter 4 Cell Processes and Energy End of Section: Cell Differentiation