Chapter 1: Single-celled Organisms and Viruses

Chapter 1: Single-celled Organisms and Viruses

Chapter 1: Singlecelled Organisms and Viruses Characteristics of Living Things Microorganisms Most living things are too small to be seen. Even the tiniest organisms are made of cells.

Very small organisms are called microorganisms. These are mostly unicellular (made of one cell). Kingdoms Remember that all living organisms are divided into kingdoms.

Most microscopic kingdoms: archaea, bacteria, and protists. Characteristics of Microorganisms Review: all living organisms have four characteristics in common. Organization all single celled organisms contain

everything they need to function in their one cell Growth unicellular organisms do not grow as large as multicellular organisms. Reproduction binary fission. Response to Stimuli (Environment) light, temperature, and touch. Needs of Microorganisms

Review: all living organisms need three things. Energy some transform sunlight, others depend on other organisms for energy. Materials water, carbon dioxide, oxygen.

Living space Viruses A virus has genetic material in a protein shell. They share many of their characteristics with living organisms, but they are not living.

They are not as complex as cells. Once viruses form they do not grow, and they only reproduce by taking over a cell. Chapter 1: Singlecelled Organisms and Viruses Bacteria and Archaea What are bacteria?

Bacteria are the simplest kind of life known on Earth. they are composes of just one cell without a nucleus (what do we call cells without a nucleus?) Genetic material is contained in loops within the cell.

Reproduce by binary fission. Bacterial Cells Bacterial cells are about 1/10 to 1/20 the size of a normal cell. Most have a covering called a cell wall

surrounds and protects the cell membrane. Contain many large molecules and structures not found in viruses. Classifying Bacterial Cells Classified by their external shapes.

Spiral bacteria: occurs in single strands. Rod bacteria: occurs singly or in chains. Round bacteria: occurs singly, in pairs, in chains, or in clusters. Archaea

Similar to bacteria but share more in common with more complex organisms. Archaea: single-celled organisms that can survive in a range of environments. They are grouped based upon where they live. Methanogens

Named for methane, the gas they produce. die if exposed to oxygen. Live in dense mud, swamps, marshes. Guts of animals (cows and termites).

Halophiles Live in very salty lakes and ponds. Some die if water is not salty enough. They can survive drying, and will begin dividing if water returns to the pond.

Halophiles halite (salt) Thermophiles Thrive in extreme heat or cold. Hot springs, hot vents in the sea, or meters deep in ice.

Chapter 1: Singlecelled Organisms and Viruses Bacteria and Archaea Bacteria Some contain chlorophyll what does this allow them to do?

They produce their own food, so they are an important food source for ocean animals and release oxygen gas. They are called producers. Example: Cyanobacteria Bacteria

Other bacteria break down dead plants and animals to help recycle matter. They are called decomposers. Bacteria Some bacteria live either inside or on the surface of other organisms.

Sometimes, this relationship causes no effect. Other times, there is a benefit to both organisms. When there is a negative relationship between the two, the bacteria is called a parasite to the host.

Example: Staphylococcus infects humans. Helpful Bacteria Bacteria that breaks down organic matter are helpful. Cities use these bacteria in sewage treatment plants. They help purify the water before it is released to bodies of water.

Some bacteria changes nitrogen gas to nitrogen compounds (fixation), which allows plants to use nitrogen to make proteins. Helpful Archaea Animals that eat plants depend on archaea. Methanogens help break down cellulose in cell

walls which makes it easier for animals to digest. Harmful Bacteria Many types of bacteria can harm humans: tuberculosis, cholera, and infant diarrhea. They can invade parts of the body and multiply in cells/tissues. They can poison the body with chemicals they release.

They can poison the body with chemicals that are in the bacteria itself. We try to prevent these infections by getting vaccinations. Chapter 1: Singlecelled Organisms and Viruses

Viruses Characteristics of Viruses When scientists first discovered bacteria, they were able to filter it out of liquids by using a sieve. When this process did not always work, they

came to the conclusion that there was something smaller than bacteria. These are now called viruses. Characteristics of Viruses Contain genetic material contained inside a protein coat called a capsid.

The capsid can be a simple tube or have several layers. They use living cells to get their DNA copied, so they are able to reproduce. They do not grow or respond to their environment.

Harmful Viruses A virus uses a cells material, energy, and processes to thrive. Can cause serious diseases such as polio, smallpox, diphtheria, or AIDS. Influenza (the flu) is a more common virus.

Harmful Viruses Viruses can also affect plants. They can have stunted growth or die because of viruses. If they infect crops, it can destroy farmland, which

impacts the farmers, community, and economy. Chapter 1: Singlecelled Organisms and Viruses Reproduction of Viruses How do viruses multiply? Viruses must use materials from living cells to make copies of their DNA.

The cells that become infected by viruses are called host cells. One every common virus is called a bacteriophage because it infects bacteria. Bacteriophage Multiplication Step 1: attachment.

The virus attaches to the surface of the host cell. Bacteriophage Multiplication Step 2: Injection. The virus injects its DNA into the host cell.

Bacteriophage Multiplication Step 3: Production. The host cell goes through its normal functions to produce copies of the viral DNA. Bacteriophage Multiplication Step 4: Assembly.

New viruses assemble from the copied DNA. Bacteriophage Multiplication Step 5: Release. The host cell bursts, and hundreds of new viruses can be released.

Chapter 1: Singlecelled Organisms and Viruses Protists

Recently Viewed Presentations

  • Hookah/Waterpipes 101  Stanford University In this presentation What

    Hookah/Waterpipes 101 Stanford University In this presentation What

    Hookah's History . Do you think that is true? …clouds made by hookah was just "water vapor" Teacher. Talking Points: (Click) Originated in ancient Persia and India and spread throughout the Middle East and Asia to Turkey during the Ottoman...
  • Présentation PowerPoint - Thomas Jefferson National ...

    Présentation PowerPoint - Thomas Jefferson National ...

    The HADES detector is installed on the GSI facility, but HADES is a european collaboration. Actually 150 persons working in about 156institutions all over Europe. 15" tot 45" ... Présentation PowerPoint Last modified by: Beatrice ramstein
  • IDEA Formal Complaint Trends - Kentucky Department of Education

    IDEA Formal Complaint Trends - Kentucky Department of Education

    IDEA Formal Complaint Trends. Sylvia Starkey. IDEA Formal Complaint Investigator. 11/21/2017. ... More formal than mediation. Less formal than due process. Procedural violations. ... PowerPoint Presentation Last modified by:
  • Kingdom Fungi - Mayfield High School

    Kingdom Fungi - Mayfield High School

    ++Mychorrhizae allow more robust plant growth ++Succession restores soil (as after volcano erupts) ++Primary decomposers on land ++Food sources -mushrooms ++Fermentation of alcoholic beverages (alcoholic fermentation by yeasts) The cellulase enzyme allows fungi to act as a decomposer, essential in...
  • Chapter 22 "Crash and Depression"

    Chapter 22 "Crash and Depression"

    Chapter 22 "Crash and Depression" Section 1 "The Stock Market Crash" Pg. 740-744. Dow Jones Industrial Average. Black Tuesday. Great Crash. Business cycle. Great Depression. Vocabulary. 1. What events led to the stock market's Great Crash in 1929? 2. Why...
  • Individual Retirement Account (IRA'S)

    Individual Retirement Account (IRA'S)

    Rollover IRA: A IRA set up to receive a 401k distribution . Inherited IRA: An IRA acquired by a beneficiary. Simplified Employee Pension (SEP-IRA): An IRA set up by a small business employer for the firm's employees.
  • CSE 2341 Digital Logic Circuits - Auburn University

    CSE 2341 Digital Logic Circuits - Auburn University

    Chapter 2 Algebraic Methods for the Analysis and Synthesis of Logic Circuits Fundamentals of Boolean Algebra (1) Basic Postulates Postulate 1 (Definition): A Boolean algebra is a closed algebraic system containing a set K of two or more elements and...
  • Robert Huckins Elizabeth Beard James Huckins Sarah Burnham

    Robert Huckins Elizabeth Beard James Huckins Sarah Burnham

    John. Huckins. Emily. Gustin. Rosalie Luella. Huckins. Lindsay Abbott. Huckins. William Elbert. uckins. John Henry. Huckins. Lilla Ann. Huckins. ElzinaEzmaRedeker ...