Book 2 Unit 2

Prokaryotes

Characteristics
- Doesn't have a nucleus or membrane-bound organelles
- Almost always single-celled
Bacteria: A domain of prokaryotes that usually have a cell and usually reproduce by cell division
- Characteristics
  - Single-celled
    - Can stick together the for strands of films
  - Round, spiral, or rod-shaped
  - They live everywhere
- Reproduction
  - Binary Fission: Reproduction in which one single-celled organism splits into two single-celled organisms
  - Steps
    - Copying the chromosomes
    - Chromosomes separate
    - One on each side of the cell
    - Cells membrane grows inward, separating the two halves
    - New cell walls form and separate the two new cells
Archaea: A domain of prokaryotes that are genetically very different from bacteria and that have unique chemicals in their cell walls
- Cell walls are chemically different
- Molecules are unique
- Can survive in extreme conditions
Bacteria
- Characteristics
  - Most amount of individuals
  - Single-celled
  - Round, Spiral, or Rod shaped
  - Lives Everywhere
- Reproduction
  - Binary Fission: Reproduction when a single-celled organism splits into two single-celled organisms
Viruses
- A virus is a microscopic particle that cannot replicate on its own.
- Characteristics
  - Gets inside cell to inject in DNA (destroys cell)
  - People, plants, animals, and prokaryotes can be infected
  - Protein coat give virus the shape
  - Not living
    - Contains genetic material but can’t perform living functions
      - Do not use energy from nutrients
      - Can’t remain homeostasis
      - Can’t grow
      - Do not respond to stimuli
      - Can’t function on its own
      - Can replicate only in a cell
- Reproduction
  - Enters host cell
    - A host is a living thing that a virus or parasite uses for resources or shelter.
    - Proteins on virus matches proteins on host
      - Virus can now invade host
  - Multiplying DNA
    - Virus enters cell or when virus’s genetic material is in cell
      - Takes over cell
      - Host makes new protein for virus
      - New parts assemble in host
        
        Creates new virus
        
        Bursts host
        
        Can stay inactive in cell

Protists

A group of eukaryotic organisms that cannot be classified as fungi, plants, or animals

Characteristics
- Single-celled or multi-celled
- Membrane-bound organelles
- Complex Structures for movement
Reproduction
- Asexual Reproduction
  - Binary Fission
  - Fragmentation
- Sexual Reproduction
  - Gametes join together
  - Spores
Types of protists
- Animal-like Protists
- Fungus-like Protists
- Plant-like protists

Fungi

Spore-producing organisms that absorb nutrients from the environment

Reproduction
- Asexual Reproduction
- Fragmentation
- Spores
- Pudding
Sexual Reproduction
- Two individuals join toge

Plants

Characteristics
- Multicellular Eukaryotes
  - Membrane bound organelles with nucleus
- Two staged life cycle
  - Sporophyte
    - Makes spores
    - Often identical to parent
  - Gametophyte
    - Gametes
      - Female= eggs
      - Male= sperms
        
        Produces eggs
- Walls and vacuoles
- Make their own food
  - Photosynthesis
  - Chlorophyll
    - Green pigment captures energy from sun
Nonvascular and vascular plants
- Vascular system: tube like tissues that transport water, nutrients to different parts of the organism
- Nonvascular
  - Diffusion
    - Water must move from environment to plant
  - Seedless nonvascular
    - All nonvascular plants are seedless
      - Produce by spreading spores
- Vascular
  - Separated into 2 systems
    - Root system
      - Supply plants with water, minerals
      - Anchors plant
  - Shoot system
    - Stems
      - Provide support
      - Transporting water, minerals and sugar
    - Leaves
      - Where food is made
      - Help prevent water loss
        
        Curved inward leaves
  - Seedless vascular
    - Most vascular plants reproduce by spores
Seed plants
- Vocab
  - Seed
    - Plant embryo enclosed in a protective coating
  - Pollen
    - A tiny structure in which sperm forms
- Classifications
  - Gymnosperm
    - Seeds that are not enclosed in a fruit
      - Cones etc…
  - Angiosperms
    - Vascular plants that produce flowers and fruits surrounding the seed
      - Reproductive system