Tiny channels
________ in the membrane called nuclear pores allow the nucleus to communicate with the cytoplasm.
Lysosomes
________ are formed from Golgi complexes and look like membrane- enclosed spheres.
Microtubules
________ are long, hollow tubes made up of protein called tubules.
Diplobacilli
________ appear in pairs after division, and streptobacilli occur in chains.
Endocytosis
________ occurs when a segment of the plasma membrane surrounds a particle of a large molecule, encloses it, and brings it into the cell.
Fin rise
________ can occur at the poles of the bacterial cell or can be evenly distributed over the entire surface of the cell.
Osmosis
________ is the net movement of water molecules across a selectively permeable membrane from an area with a high con- centration of water molecules (low concentration of solute mol- ecules) to an area of low concentration of water molecules (high concentration of solute molecules)
Selective permeability
________ indicates that certain molecules and ions are allowed to pass through the membrane but others are stopped.
nuclear division
During ________, the chromatin could form shorter and thicker rod- like bodies called chromosomes.
electron microscope
When viewed with a(n) ________, bacterial plasma membranes often appear to contain one or more large, irregular folds called mesosomes.
Cocci
________ are usually round but can be oval, elongated, or flattened on one side.
Pili
________ are usually longer than fimbriae and number only one or two per cell.
extracellular polymeric
A glycocalyx that helps cells in a biofilm attach to their target environment and to each other is called a(n) ________ substance (EPS)
Glycocalyx
________ is the general term used for substances that surround cells.
vacuole
A(n) ________ is a space or cavity in the cytoplasm of a cell that is enclosed by a membrane called a tonoplast.
Proteins
________ attached to carbohydrates are called glycoproteins, and lipids attached to carbohydrates are called glycolipids.
active transport
In performing ________, the cell uses energy in the form of ATP to move substances across the plasma membrane.
core polysaccharide
The ________ is attached to lipid A and contains unusual sugars.
double membrane
A chloroplast is a(n) ________- enclosed structure that contains both the pigment chlorophyll and the enzymes required for the light gathering phases of photosynthesis.
mitochondria
They have a number of membrane- enclosed organelles, including ________, endoplasmic reticulum, Golgi complex, lysines, and sometimes chloroplasts.
DNA
The nucleus also contains most of the cells ________, which is combined with several proteins, including some basic proteins called histones.
Ribosomes
________ are found free in the cytoplasm.
positive bacteria
In most gram- ________, the cell wall consists of many layers of peptidoglycan, forming a thick, rigid structure.
chromatin
When the cell is not reproducing, the DNA and its associated proteins appear as a threadlike mass called ________.
organelles
Elongated, irregularly shaped ________ called mitochondria appear throughout the cytoplasm of most eukaryotic cells.
Division
________ of the cytoplasm and other organelles follows so that the two cells produced are identical to each other.
O polysaccharide
The ________ extends outward from the core polysaccharide and is composed of sugar molecules.
hypertonic solution
A(n) ________ is a medium having a higher concen- tration of solutes than that inside the cell.
cytoplasm of eukaryotic cells
Within the ________ is the endoplasmic reticulum, or ER, an extensive network of flattened membrane sacs or tubules called cisternae.
isotonic solution
A(n) ________ is a medium in which the overall concen- tration of solutes equals that found inside a cell.
nuclear envelope
Within the ________ are one or more spherical bodies called nucleoli.
Prokaryotes
________ and eukaryotes both contain nucleic acids, proteins, lipids, and carbohydrates.
thin structure
The plasma (cytoplasmic) membrane (or inner membrane) is a(n) ________ lying inside the cell wall and enclosing the cyto- plasm of the cell.
Bacteria
________ may be spherical- shaped coccus, rod- shaped bacillus, and spiral.
Simple diffusion
________ is the net (overall) movement of mol- ecules or ions from an area of high concentration to an area of low concentration.
cell wall
If the substance is organized and is firmly attached to the ________, the glycocalyx is described as a capsule.
vesicles
The proteins are modified and moved from one cistern to another via transfer ________ that bud from the edges of the cisternae.
Osmotic pressure
________ is the pressure needed to stop the flow of water across the selectively permeable membrane.
prokaryotic cells
The plasma (cytoplasmic) membrane of eukaryotic and ________ is very similar in function and basic structure.
cytoplasmic streaming
The movement of eukaryotic cytoplasm from one part of the cell to another, which helps distribute nutrients and move the cell over a surface, is called ________.
Eukaryotic membranes
________ contain carbohydrates, which serve as attachment sites for bacteria and as receptor sites that assume the role in such functions as cell recognition.
Smooth ER
________ extends from the rough ER to form a network of membrane tubules.
transport vesicle
The ________ fuses with a cistern of the Golgi complex, releasing proteins into the cistern.
hypotonic solution
A(n) ________ outside the cell is a medium whose con- centration of solutes is lower than that inside the cell.
Cocci
________ that remain in pairs after dividing are called diplococci; those that divide and remain attached in chainlike patterns are called streptococci.
Glycocalyx
________ is a layer of material containing substantial amounts of sticky carbohydrates.
Organelles
________ are structures with specific shapes and specialized functions and are characteristic of eukaryotic cells.
cell wall
If a substance is unorganized and only loosely attached to the ________, the Glycocalyx is described as a slime layer.
double membrane
The nucleus is surrounded by a(n) ________ called the nuclear envelope.
Bacteria
________ often contain small, usually circular, double- stranded DNA molecules called plasmids.