Chapter 2 Viruses and Bacteria Section 1 Viruses

Section 1: Viruses- Objectives By the end of this lesson, you should be able to: u Give reasons why viruses are considered to be non-living u Describe the basic structure of a virus; u Explain how viruses multiply

u 1. virus A small, nonliving particle that invades and then reproduces inside a living cell.

u 2. host An organism that provides a source of energy or a suitable environment for a virus or for another organism to live.

u 3. parasite An organism that lives on or in a host and causes harm to the host.

u 4. bacteriophage A virus that infects bacteria.

u 1. Biologists consider viruses to be nonliving because viruses are not cells _______. Viruses do not use energy grow _______ to _____ or to respond _______ to their surroundings.

u 2. Viruses can only multiply when they Inside a living cell are __________.

u 3. List four ways viruses can be named – 1) After the disease it causes. Ex. Polio virus After the organism they infect. Ex- Tomato mosiac – 2) virus – 3) After the place where it was first found. Ex. Ebola virus in Africa – 4) After people. Ex, Epstein-Barr virus. Named after scientists identified virus that causes mononucleosis

u 4. All viruses have two basic parts: the outer coat __________that protects ________the virus, and the inner coat ________ that is made of genetic material ________.

u 5. Once inside, a virus’s Genetic material ___________ takes over functions the cell’s ________.

u 6. Common cold _________ is an example of an active virus, The virus that causes cold sores is an while___________ example of a hidden virus. u Read pages 51 -53. How Viruses Multiply/Exploring.

Chapter 2 Viruses and Bacteria Section 2 Bacteria

Section 2: Bacteria- Objectives By the end of this lesson, you should be able to: u Describe ways in which bacteria cells are different from all other organisms’ cells u List positive roles that bacteria play in people’s lives u Name the two kingdoms of bacteria and tell how bacteria reproduce and survive.

u Review- cytoplasm The region of a cell located inside the cell membrane (in prokaryotes) or between the cell membrane and nucleus (in eukaryotes); contains a gel-like material and cell organelles.

u Review-ribosome A tiny structure located in the cytoplasm of a cell where proteins are made.

u 1. flagellum A long, whiplike structure that extends out through the cell membrane and cell wall.

u 2. binary fission A form of asexual reproduction in which one cell divides to form two identical cells.

u 3. asexual reproduction The reproductive process that involves only one parent and produces offspring that are identical to the parent.

u 4. sexual reproduction The reproductive process that involves two parents who combine their genetic material to produce a new organism, which differs from both parents.

u 5. conjugation The process in which a unicellular organism transfers some of its genetic material to another unicellular organism.

u 6. respiration The process of breaking down food to release its energy.

u 7. endospore A small, rounded, thick-walled, resting cell that forms inside a bacterial cell.

u 8. decomposer An organism that breaks down large chemicals from dead organisms into small chemicals and returns important materials to the soil and water.

Notes Bacteria ___________ prokaryotes are___________. The genetic material in their cells is not nucleus contained in the _________. u 1.

u 2. List the three basic shapes of bacteria and draw each one. u First shape- spherical

u 2. List the three basic shapes of bacteria and draw each one. u Second shape- Rod like

u 2. List the three basic shapes of bacteria and draw each one. u Third shape- spiral

3. List the cell structures present in a bacterial cell u 1. Cell wall u u 2. ribosome u 3. Cell membrane u 4. Flagellum u 5. Genetic material u 6. Cytoplasm

u 4. Under ideal conditions, Bacteria can 20 reproduce once every _____ minutes.

u 5. List five good things bacteria do in our world. u 1. Fuel. Ex. Methane produced by archaebacteria u 2. Food. Ex. Cheese, yogurt, apple cider u 3. Environmental Recycling. Ex. Decomposers. u 4. Environmental Clean up – bacteria to clean up oil spills. u 5. Health and Medicine – bacteria that helps you digest your food

Chapter 2 Viruses and Bacteria Section 3 Integrating Health: Viruses, Bacteria, and Your Health

Section 3: Viruses, Bacteria, and Your Health- Objectives By the end of this lesson, you should be able to: u Describe how infectious diseases spread from person to person. u Describe some ways in which infectious diseases can be treated or prevented.

u 1. infectious disease An illness that can pass from one organism to another.

u 2. toxin A poison that can harm an organism.

u 3. antibiotic A chemical that can kill bacteria without harming a person’s cells

u 4. vaccine A substance that stimulates the body to produce chemicals that destroy viruses, bacteria, or other disease-causing organisms.

Notes (read pg 69 -70 first) u 1. Explain the 4 ways infectious diseases spread, and give an example of each. u 1. Contact with Infected Person-touching, hugging, kissing, sneezes, coughs u 2. Contact with Contaminated Object-eating utensils, food water, cups u 3. Contact with an Animal-rabies, mosquitoes u 4 Contact with Environmental Sources-food, water, soil

u Change your number 2 to the following: u 2. For most infectious diseases, the best treatment is: Bed rest u __________ resting u __________ drinking lots of fluids u __________ eating well balanced meals u __________

u 3. Bacterial diseases ______________ can be cured with antibiotics __________, while with Viral diseases ______________ you can only treat the symptoms _________.

u 4. Penicillin (an antibiotic) ______________ works by weakening the Cell wall ______________ and cells causing the _________ to burst ___________.

u 5. The best way to protect yourself against infectious diseases is to: Keep your body healthy u A. ____________ Eat nutritious foods u B. ____________ Get plenty of rest, fluids, and exercise u C. ____________ Washing hands, not sharing utensils, etc. u D. ____________