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Document 1794859
Bubonic plague is one of the deadliest pandemics in human history. It killed 3060% of Europe’s population between 1348-1350 and took 150 years for Europe's population to recover. Since AIDS was first recognized in 1981, it has led to the deaths of more than 25 million people, making it one of the most destructive diseases in recorded history. Dairy product produced by fermentation of milk. People have been making and eating yogurt for atleast 5,500 years! Global outbreak that began in Mexico, approximately 600,000 people infected world-wide. Humulin was the first medication produced using modern genetic engineering techniques in which actual human DNA is inserted into a host cell. The host cells are then allowed to grow and reproduce normally, and due to the inserted human DNA, they produce a synthetic version of human insulin. Humulin can be used as a treatment for diabetes. •Infectious Disease: any change, other than injury, that disrupts the homeostasis of the body. There are different agents of disease, the most common being: bacteria, protists, fungi, and some animals. •Homeostasis- the process by which organisms keep conditions relatively constant internally, even when external conditions do not remain constant. • Physical contact •Infected food or water •Vectors- animals that carry pathogens from person to person • Fights infection 2 different ways: 1. Nonspecific Defenses •First Line of Defense: skin and mucus! •Second Line of Defense: inflammation! Inflammation is when your white blood cells go to your infected tissue and causes it to become red and swollen. This can also raise your temperature and cause a fever. 2. Specific Defenses •The immune system reacts and attacks a specific pathogen. The defenses are called an immune response. The trigger is called an antigen. •There are two types of cells that recognize specific threats: B cells and T cells. •Characteristics of Living Things 1. Made up of cells 2. Reproduce (sexual or asexual) 3. Have DNA 4. Grow and Develop 5. Obtain materials and energy 6. Respond to their environment 7. Change over time Viruses and Living Cells Characteristic Made up of cells Reproduction Have DNA Grow and Development Obtain and Use Energy Respond to the Environment Change Over Time Virus No Cell Yes Must have a host Sexual or asexual Yes Yes No Yes No Yes No Yes Yes Yes • A non-living parasite • Must use living cells to reproduce. All viruses enter and take over host cells to produce more viruses. Nucleic Acid- DNA or RNA in the inner core containing information to make copies of the virus. Capsid- Outer protein coat that surrounds the DNA or RNA. This makes them very specific to what they infect. The ‘spikes’ sticking out fit like a puzzle piece to trick cells into letting them in. The virus attaches to the host cell , enters it and takes over. Only then can the virus replicate. http://www.tvdsb.on.ca/westmin/science/sbi3a1/Bacvirus/Virusrep.htm A typical lytic cycle takes about 30 minutes and produces about 200 new viruses. The virus enters the cell, copies itself, and causes the cell to burst. The virus enters the cell and instead of immediately taking over the host’s genetic material, the viral DNA is combined into the host cell’s chromosome. This type of infection can stay as a permanent fixture in the hosts DNA reappearing as a viral outbreak at different times throughout the hosts life (like herpes-caused by the herpes simplex I Virus). A virus recognizes and attaches to a host cell when one of its proteins interlocks with a molecular shape that is the receptor site on the host cell’s plasma membrane. The recognition and attachment process is like two pieces of a jigsaw puzzle fitting together. Rhinoviruses cause the common cold HPV (Human papillomavirus) can cause cervical cancer in women Herpes simplex viruses cause mouth and/or genital sores, lesions, and ulcers. Influenza viruses cause the flu HIV (Human Immunodeficiency Virus) causes AIDS and weakens the immune system Alive Capable of reproducing on its own Capable of growing and developing during its ‘life’ cycle Antibiotics DO NOT work on viruses. Most human viral infections can be fought off by the immune system—boost the immune system with lots of water and rest. Vaccines are preventative!!! (Vaccines will not cure you if you are already sick. They stimulate the immune system to create an immune response that recognize a certain virus. These antibodies patrol your body and if they recognize that virus…they call in reinforcements and your immune system goes into battle!) DNA viruses: herpes simplex virus (HSV) Varicella zoster virus (VZV) •Chickenpox •Shingles- Re-activation of latent infection Ebola hemorrhagic fever (Ebola HF) is a severe, often-fatal disease in humans and nonhuman primates Appeared sporadically since its initial recognition in 1976. Transmission arthropod bites. No known treatment. The first virus to be identified was a plant virus, called tobacco mosaic virus 400 identified viruses that infect plants with 1000 different diseases Cause stunted growth and crop losses • Prokaryotic (no nucleus) • Unicellular • Autotrophs or heterotrophs • Aerobic (uses oxygen) or anaerobic • Can be motile using pili or flagella Bacteria come in a wide range of shapes, sizes and colors! Bacillus Spirulina Bordetella Clostridium Staphylococcus Streptococcus Escherichia Salmonella 1. Binary Fission- bacteria doubles their size and DNA, then divide in half to produce two identical daughter cells. 2. Conjugation- a hollow bridge forms between two bacteria and they exchange DNA. 3. Spore Formation- some bacteria grow spores when conditions are unfavorable. An endospore is formed when bacteria produce a thick internal wall that closes off all the DNA and small portion of the cytoplasm. Spores can remain dormant for long periods of time. Allows bacteria to survive extreme heat, dryness, or lack of nutrients that might otherwise kill them. Binary Fission 1 bacterium can become 1/2 million in 6-7 hours Conjugation Draw these! • Digestion- Escherichia coli is in our gut and aides in digestion. Other bacteria in the digestive tract provide us with different vitamins we need. • Food- Lactobacillus bulgaricus is found in cheese and yogurt! • Decomposers- help break down dead and decaying stuff. • Nitrogen-fixation- turns the nitrogen in the air into a usable form that plants need. • Industry- can digest petroleum, which aides in oil spills. • Water treatment- removes waste and poisons from the water. • Staphylococcus aureus-food poisoning when toxins are ingested • Streptococcus pyogenes-causes strep throat—red spots on your throat are red blood cells the bacteria have destroyed • Clostridium botulinum-produces toxins that cause paralysis for 4-6 months (botox injections are made of these toxins!!!) • Pasteurization is used to remove bacteria from food • Antiseptics can kill bacteria on tissues • Antibiotics are used to kill bacteria that have entered the body (penicillin, amoxicillin, tetracycline, ciproflaxin) • Vaccines can prevent bacterial infections by stimulating the immune system • Also- cook and refrigerate your food properly, and wash hands NOT classified because THEY ARE NOT ALIVE Classified into the Kingdom Eubacteria or Archeabacteria Non-living parasite Living Cannot reproduce on their own (uses a host cell) Can reproduce sexually or asexually Contain DNA or RNA inside Contain circular DNA inside a protective coating (capsid) a cell membrane and cell wall Always pathogenic Can be helpful or pathogenic Bacteria vs. Virus Characteristic Number of Cells Does it reproduce on its own? Type of Nucleic Acid Form of Nutrition Is it living? Does it cause disease? Can it be helpful? Can antibiotics kill it? Can it move on its own? What does it look like? Bacteria Virus Use the following words: o o o o o o o o Alive Float/Don’t move on own Blows up cells Eat sugar and O2 Not alive Swim Cells Built by host cell o o o o o Don’t need to eat Reproduce Can’t reproduce on own DNA/RNA Makes waste that kills cells