Biology 7.1-7.2


Terms in this set (...)

Smallest unit of a living organsim.
Robert Hooke
Scientist who discovered the cell. Using CORK.
Anton van Leeuwenhoek
First person to observe living microorganisms. Also, found that if you put different lenses together you can magnify.
Matthias Schleiden
German Botanist that concluded that plants are made up of cells.
Theodor Schwann
Concluded that animals were also made of cells.
Rudolf Virchow
Concluded that new cells can be produced only from the division of existing cells.
Cell Theory
- All living things are made up of cells.
- Cells are the basic units of structure and function in living things.
- New cells are produced from existing cells.
Light or Electrons
Most microscopes use lenses to magnify the image of an object by focusing ____________ or ____________.
Compound Light Microscpe
Allows light to pass through a specimen and contains two lenses (objective and ocular) to form an image.
- Can usually magnify up to 1000x.
- Can see cellular structures one millionth of a meter in diameter.
Dyes give off light of a particular color when viewed at certain wavelengths is called...
Electron Microscope
Uses a beam of electrons that are focused by a magnetic field.
Transmission Electron Microscope (TEM)
-Electrons shine through the specimen and you get a more detailed image.
-Thin samples.
Scanning Electron Microscope (SEM)
- Electrons bounce off the SURFACE and you get an image of the specimen.
- Samples do NOT have to be thin.
- 3D
Photos of an object seen through a microscope.
Cell Membrane
Thin, flexible barrier that surrounds all cells; regulates what enters and leaves the cells.
Plasma Membrane
Cell membrane is also known as _____________.
A large membrane-enclosed structure that contains genetic material in the form of DNA and controls many of the cells activities.
Plural Nuclei
Nucleus is also known as ____________.
- Cells that enclose their DNA in a nucleus.
- Larger and more complex.
- Can be unicellular or multicellular organisms.
- Protist, Plants, Fungi, Animals
- Cells that do NOT enclose DNA in the nucleus.
- Smaller and simpler.
- Carry out all activities associated with living things.
- Bacteria
Most living cells are ________________.
Electrons can be scattered by ______ - samples need to be studied in a vacuum.
Electrons can be scattered by air - samples need to be studied in a ______________.
Samples need to be __________ preserved and are nonliving when viewed.
Samples need to be chemically preserved and are ___________ when viewed.
Eukaryotic Cells
_________________ can be divided into two main parts. Nucleus and Cytoplasm.
Nucleus and Cytoplasm
Eukaryotic cells can be divided into two main parts. _____________ and ________________.
The environment inside the cell (plasma) membrane and outside the nucleus. Made up of a semifluid material that houses organelles.
Specialized structures that carry out specific functions inside the cell.
Contains DNA and the coded instructions for making proteins and other important molecules.
Found in the nucleus in the form of chromatin.
DNA bound to proteins.
Site where ribosome assembly begins.
The nucleolus is located in the ______________.
Large sac-like, membrane enclosed structures that store materials like water, salts, proteins, and carbohydrates.
Membrane-enclosed structures that store and move materials between cell organelles and in and out of cells.
Small organelles filled with enzymes that break down lipids (fats), carbohydrates, and proteins into smaller molecules that can be used by the rest of the cell. Also break down unused organelles. Known as the "clean-up crew".
Helps the cell maintain its shape and is involved in movement.
Threadlike structures made up of a protein called actin. Produce a flexible framework that supports the cell and helps cells move.
Hollow structures made up of proteins known as tubulins. They maintain cell shape and are important in cell division. Also build cilia and flagella.
Structure in animal cells that organize the cell for division. Occur in pairs. Found in animal cells and some protist, not plants.
Short hair like projections that produces movement.
Structure that produces movement in a wavelike motion which enables the cell to move.
Small particles of RNA and protein found throughout the cytoplasm. Make proteins by following the instructions on DNA.
Endoplasmic Reticulum
An internal membrane system where lipid components of the cell membrane are assembles along with proteins and other materials that are exported from the cell.
Rough ER
Protein Synthesis
Smooth ER
Contains collections of enzymes that perform specialized task.
Golgi Aparatus
Modifies, sorts, and packages proteins and other materials from the endoplasmic reticulum for storage in the cell or release outside the cell.
Capture the energy from sunlight and convert it into food that contains chemical energy in a process called photosynthesis. Contains chlorophyll and is only found in plant cells.
The process of capturing energy from the sunlight and converting it into food that contain chemical energy.
Convert the chemical energy stored in food into compounds that are more convenient for the cell to use. Makes ATP for energy. Contains an inner and outer membrane and is found in nearly all eukaryotic cells.
Cell Wall
Strong, supporting layer around the cell membrane. Main function is to support, shape, and protect. Not found in animal cells. Porous to let some substances pass through easily.
Cell Membrane
Made up of a double layered sheet called the lipid bilayer.
Lipid Bilayer
Gives the cell membrane a flexible, but strong barrier.
Fatty acid portion of a lipid is _______________.
Head end of a lipid is ______________.
Fluid Mosaic Model
Molecules such as proteins and carbohydrates are embedded in the lipid bilayer.
Selectively Permeable
Allows certain substances in while keeping others out.