cells

• The nucleus contains the cell's genetic material and controls the cell's activities.
• Cells are an important part of your life.
• Some micro-organisms live in the digestive systems of multicellular

  organisms. Here, they feed on food particles that pass through

  the intestines. In humans, this relationship is an important part of

  digestion. Micro-organisms that live in the intestines contribute to

  the health of your intestines, produce vitamins, and help break down

  foods that would otherwise be indigestible
• Some micro-organisms can cause health problems, such as acne, strep

  throat, and diarrhea, in humans. Some micro-organisms can make

  people temporarily ill, while others can cause serious diseases. Several

  bacterial diseases have killed millions of people throughout history.
• Sometimes, cells are not able to function properly. Th is may happen

  for several reasons. An organism may inherit damaged genes that

  cause cells to fail, or environmental factors may damage cells.
• • Living things are called organisms and are composed of smaller parts working together to carry out life processes.
  • Cells are organisms with organelles that work together to keep the cell alive.
  • Unicellular organisms are made up of only one cell and are usually too small to be seen without a microscope.
  • Multicellular organisms are made up of many cells working together.
• Living things are classified into five groups: plants, animals, fungi, protists, and bacteria.
• Living things are called organisms and are composed of smaller parts working together to carry out life processes
• Cells are organisms with organelles that work together to keep the cell alive
• Unicellular organisms are made up of only one cell and are usually too small to be seen without a microscope
• Multicellular organisms are made up of many cells working together
• Living things are classified into five groups: plants, animals, fungi, protists, and bacteria
• Plants can make food through photosynthesis and live on land or in water
• Animals can be vertebrates (with a backbone) or invertebrates (without a backbone)
• Five main vertebrate groups: Mammals, Birds, Reptiles, Fishes, Amphibians
• Fungi usually obtain nutrients by absorbing them from dead or decaying matter and cannot carry out photosynthesis
• Protists are a diverse group of organisms found in wet environments such as ponds, rivers, and mud and can be unicellular or multicellular
• Some protists can perform photosynthesis
• Bacteria are the simplest and most abundant unicellular organisms on Earth
• Bacteria do not have a nucleus
• Some types of bacteria gather into groups called bacterial colonies
• Example: Escherichia coli (E. coli)
• Unicellular organisms consist of only one cell and are too small to be seen without a microscope
• Examples of unicellular organisms include diatoms, bacteria, fungi, yeast, and amoebae
• Unicellular organisms can carry out essential functions independently, such as movement, obtaining nutrients, and gas exchange
• Unicellular organisms meet their nutritional needs through capture of food and nutrient absorption
• Multicellular organisms are composed of more than one cell, and these cells work in coordination to ensure the proper functioning of the organism's various systems
• Muscular system enables movement through contraction and relaxation of muscles
• Skeletal system provides framework and support for movement
• Nervous system coordinates movement by transmitting signals to muscles
• Multicellular organisms encompass a wide range of life forms, including invertebrates and vertebrates
• Plants do not possess specific systems for movement like animals, instead, they demonstrate movement by gravitating towards light sources
• Multicellular organisms collaboratively function to facilitate movement and other essential activities
• Unicellular Organisms:

  • Composed of a single cell
  • Can perform all essential life functions within one cell
  • Relatively simple in structure
  • Examples include bacteria, amoebas, and diatoms
  • Reproduce asexually through methods like binary fission
• Multicellular Organisms:

  • Composed of multiple cells that are organized into tissues, organs, and systems
  • Cells are specialized for specific functions
  • Can exhibit complex behaviors and movements
  • Examples include plants, animals, and humans
  • Reproduce sexually and undergo embryonic development
• Fungi: organisms that usually obtain nutrients from dead or decaying matter and cannot carry out photosynthesis; nutrients are typically absorbed
• Protist: an organism that is neither plant nor animal but shares many characteristics of both; usually unicellular but can be multicellular
• Bacteria is the most basic of all unicellular organisms, it lacks a nucleus
• Vertebrate: an animal with a backbone
• Invertebrate: an animal without a backbone