42 terms

Biology 7.1 to 7.4


Terms in this set (...)

Cell theory
All living things are made up of cells. They are the basic units of structure and function in living things.
Cell membrane
Surrounds cells. Thin, flexible barrier
Large membrane enclosed structure that contains the cells genetic material in the form of DNA. Controls many of the cells activities.
Eukaryotes(plant cell)
Cells that enclose their DNA in nuclei
Prokaryotes(animal cell)
Cells that do NOT enclose their DNA in nuclei
The fluid portion of the cell outside the nucleus
Cellular structures that act if they are specialized organs. "Little organs"
Large, saclike membrane enclosed structures in cells. They store materials such as water, salts, proteins, and carbohydrates
Small membrane enclosed structures. Used to store and move between cell organelles, as well as to and from the cell surface
Small organelles filled with enzymes that function as the cells cleanup crew. Lysosomes perform the vital function of removing "junk" that might otherwise accumulate and clutter up the cell. They breakdown lipids, carbohydrates, and proteins into small molecules that can be used by the rest of the cell.
Protein filaments that give eukaryotic cells their shape and internal organization
Thread like structures made up of a protein called actin. They support cells, help move cells, and to crawl along surfaces
Hollow structures made up of proteins known as tubulins. They maintain their cell shape
Located near the nucleus and helps to organize cell division. NOT found in plant cells
Small particles of RNA and protein found throughout the cytoplasm in all cells. They produce proteins by following coded instructions that come from DNA
Endoplasmic reticulum
Internal membrane system in eukaryotic cells. ER is where lipid components of the cell membrane are assembled along with proteins and other materials that are exported from the cell
Rough ER
Newly made proteins leave these ribosomes and are inserted into the rough ER where they may be chemically modified. Ribosomes on the surface
Smooth ER
Ribosomes NOT on the surface. They contain collection of enzymes that perform specialized tasks, including the synthesis of membrane lipids and the detoxation of drugs
Golgi apparatus
Proteins move from the ER --->Golgi apparatus. Modifies, sorts, and packages proteins and other material from the ER for the storage in the cell or release outside the cell.
Biological equivalents of solar power plants. They capture the energy from the sunlight and convert it into food, that contains chemical energy in a process called photosynthesis
Power plant of the cell. Their function is to convert chemical energy stored in food into compounds that are more convenient for the cell to use
Cell wall
Strong, supporting layer around the membrane. Provides support and protection for the cell
Lipid bilayer
Double layered sheet. Gives the cell membranes a flexible structure and forms a strong barrier between the cell and its surroundings
Selectively permeable
Some substances can pass across them and others cannot
The process by which particles move from an area of high concentration to an area of lower concentration
Facilitated diffusion
Molecules that cannot directly diffuse across the membrane and pass through special protein channels
Water channel proteins. They allow water to pass right through them
The diffusion of water through a selectively permeable membrane. Moves left to right
When the concentration is the same on both sides of the membrane, the two solutions will be isotonic(same length)
The more concentrated sugar solution at the start of the experiment was hypertonic(Same Length), compared to the dilute sugar solution
The dilute sugar was hypotonic(below strength)
Osmotic pressure
The net movement of water out of or into s cell exerts a force known as osmotic pressure. Almost always hypertonic to fresh water
Active transport
The movement of materials against a concentration difference. Requires energy
Molecular transport
Small molecules and ions are carried across membranes by proteins in the membranes that act like pumps
Bulk transport
Larger molecules and solid clumps of material may be transported by movements of the cell membrane known as the bulk transport
Relatively constant internal physical and chemical conditions that organisms maintain
Group of similar cells that perform a particular function
Group of tissues that work together to perform closely related functions
Organ system
Group of organs that work together to perform a specific function
On or in a cell, a specific protein to whose shape fits that as a specific molecular messenger, such as a hormone
Process of taking materials into the cell by means of infoldings, or pockets, of the cell membrane. BRING MATERIALS FROM THE OUTSIDE IN
Many cells release large amounts of material from the cell