Bio - Unit 1 Cells

Experiment -
Control - used for comparison purposes, doesn’t change

Constants - things that stay the same across the experiment  

Independent Variable - On x-axis, the part that is changed

Dependent Variable - On y-axis, the part that is affected because of the Independent Variable   


Characteristics of life

  1. Made of 1+ cells

  2. Can reproduce as a species

  3. Can maintain homeostasis

  4. Requires energy (metabolism)

  5. Can adjust to the environment

    1. stimulus

    2. response

  6. Adapt and evolve as a species

  7. Growth and development as individuals

  8. Organization, obtain/use materials and energy


Cell Theory

  1. Composition - composed of 1+ cells

  2. Function - Cell is the basic unit of structure and life

  3. Origin - All cells arise from pre-existing cells


Prokaryotes

  • No nucleus, curvy DNA found in the nucleoid region

  • Extremely small (0.1-0.5)

  • Unicellular and simples structure

  • Bacteria

    • Archaebacteria

      • First type of life on Earth

      • Still exist today in extreme enviroments

    • Eubacteria

      • “Newer” bacteria

      • These are the everyday bacteria we come in contact with


Eukaryotes

  • Membrane-bound organelles and nucleus that protects the DNA

  • Complex organelles

  • Larger size (10-100)

  • Multicellular and unicellular with specialized systems

  • Includes plants, animals, and fungi


Parts of ALL cells

  • Cell membrane

  • Cytoplasm

  • DNA

  • Ribosomes


Organelles and functions

Nucleus - Stores DNA/genetic code

Rough ER - Transports proteins (has ribosomes on it)

Smooth ER - Transports lipids (no ribososmes)

Golgi Apparatus - Modifies, packages, and sorts proteins

Ribosomes - Makes proteins

Vesicles - Transports through the cytoplasm

Lysosomes (animals) - Breaks down wast using digestive enzymes

Cell membrane - Determines what can enter/leave the cell

Mitochondria - Makes energy (ATP)

Central Vacuole (plants) - Stores water and minerals

Cell Wall (plants) - Structure ad support (creates the rigid structure)

Chloroplast (plants) - Converts sunlight energy to chemical (glucose) energy (Photosynthesis)


Cell Specialization

  • Everyone started as a zygote then it divided by mitosis to form an embryo

  • Embryos continue to divide and their cells are called emrbyonic stem cells

  • Stem cells - undifferentiated cells that can become any type of cells

  • Your body has 46 chromosomes, but stem cells activate different genes which allows cells to turn into different types of cells with different functions

  • Embryonic stem cells

    • Derived from early embryos

    • Pluripotent - can become any cell type in the body

    • Highly versatile and have unlimited potential

  • Adult stem cells

    • Found in adult tissues (bone marrow)

    • Multipotent - limited to certain cell types

    • Important for tissue repair and regeneration


Biological Organization

  1. Cells

  • Smallest unit of life

  • All living things are made of cells

  • Cells carry out basic life process (growth)

    • e.x. red blood cells, nerve cells

  1. Tissues

  • A group of similar cells working together to perform a specific function

  • Cells in a tissue have similar structures and jobs

  • Examples

    • Muscle - contracts to cause movement

    • Nervous - transmits signals

    • Epithelial - covers surfaces and lines organs

    • Connective - supports and protects (bones, blood)

  1. Organs

  • A structure made of different types of tissue working together

  • Performs a specific, complex function

    • Heart (muscle, nerve, and connective tissues)

    • Stomach, lungs, leaf (plant organ)

  1. Organ systems

  • A group of organs working together to carry out major body functions

  • Examples in humans

    • Circulatory - heart, blood, blood vessels

    • Digestive - stomach, intenstines, liver

    • Respiratory - Lungs, trachea

    • Nervous - brain, spinal chord, nerves

  1. Organism

  • A single, completer living thing

  • Can be unicellular or multicellular

    • Humans, dogs, trees, amoeba

Mutation - In the DNA of a zygote affects the whole organism because every cell in the bodt develops from that original cell and inherits the same mutated DNA


DNA transportation

The DNA is held in the nucleus. When a protein is needed, a small portion of the DNA is copied and then sent through the nuclear pore. It travels through the ER and arrives at a ribosome, where the information in the copy of DNA will be used to make the protein coded for in the instructions. Once the protein is made it will be shipped to the golgi apparatus for modification. It is shipped out of the golgi in a vesicle to wherever inside or outside the cell it is needed.