they use light and glass to magnify an image
How light microscopes work?
How many millimeters are in a centimeter?
The idea that all living things are composed of cells and that all cells come from other cells defines
Archaea are composed of _____ cells.
What structure is exclusively associated with prokaryotic cells?
Contains the cell's DNA
The nucleoid region of a prokaryotic cell
______cells lack a membrane-enclosed nucleus
A bacterial cell's DNA is found in its
Are plants cells
You are told that the cells on a microscope slide are plant, animal, or bacterial. You look at them through a microscope and see cell walls and membrane-bound organelles. You conclude correctly that the cells _________
Nonpolar molecules such as CO2
Plasma membranes are permeable to
The nucleus of a cell
Long fibers of DNA and protein found in the nucleus are called
Chloroplasts and cell walls
Unlike animal cells, plant cells have ____ and ____.
Unlike plant cells, animal cells have _____.
What structure is used by prokaryotes for attaching to surfaces?
To manufacture ribosomal RNA
The function of the nucleolus is ___________
A small cell lived inside a larger cell to the benefit of both cells
What does the endosymbiosis hypothesis propose?
Embedded in an extracellular matrix
Most animal cells are______
Individual proteins and phospholipids that can drift in phospholipid bilayer
The fluid mosaic model describes the plasma membrane as consisting of _________________________
"kinks" in their tails caused by the presence of a double bond between carbons
Membrane phospholipids often have
Most functions of a cell membrane are performed by _______
the plasma membrane allows some substances to enter or leave a cell more easily than others
Plasma membranes are selectively permeable. This means that
easily pass through a membrane's lipid bilayer
Small, nonpolar, hydrohobic molecules such as fatty acids...
Structure and function
All cells are enclosed by a plasma membrane that is similar in ____ and ______.
Oxygen crosses a plasma membrane by
Diffusion does not require the cell to expand ATP. Therefore, diffusion is considered a type of
isotonic to its environment
A cell that neither gains nor loses water when it is immersed in a solution is
Transport proteins, down
Facilitated diffusion across a biological membrane requires ____ and moves and substance ______ its concentration gradient
Which kind of process can move a solute against its concentration gradient?
Most of a cell's enzymes are
changing the enzyme's three-dimensional shape
Heating inactivates enzymes by
a zinc atom
What substance could be a cofactor?
What substance is a coenzyme?
It lowers the activation energy of the reaction.
When an enzyme catalyzes a reaction,
Substrates bind to an enzyme's ______ site
the region of an enzyme that attaches to a substrate
The active site of an enzyme is
The molecules responsible for membrane transport are
the diffusion of water
Osmosis can be defined as
1. Cell is the basic function and structure of organelles
2. Cells come from other cells
3. All things are made up of cells
What are the 3 parts of the cell theory?