CHAPTER 4 Flashcards
Characteristics:
- have no nucleus
- one, circular chromosome of pure DNA
- no membrane-enclosed organelle
- cell walls are composed of the complex carbohydrate peptidoglycan
- reproduces by binary fission
- small simple cells
- always unicellular
This is called:
Prokaryotes
The separate gene-carrying body is called
Chromosome
Characteristics:
- DNA is found in the cells nucleus
- several linear chromosomes of DNA and protein
- have membrane-enclosed organelles
- cell walls, if present, are chemically simple
- cell division is usually by mitosis
- large, complex cells
- can be unicellular, but also multicellular
- can reproduce by sexual reproduction
This is called
Eukaryotes
What are the 3 types of shapes?
- Cocci- round or sphere-shaped cells
- bacilli- straight, rod-shaped cells
- spiral- curved rods, never straight
a pair of cells
Diplo-
a chain of cells
strepto-
a group of four cells
tetrad-
a cube of eight cells
sarcinae-
a grapelike cluster of cells
staphylo-
- many prokaryotes secrete on their surface a glucocalyx
- meaning “sugar coat” it is the general term for substances that surround cells
- a viscous (sticky) gelatinous (jelly-like) substance external to the cell wall.
- composed of polysaccharide (carbohydrate) polypeptide (protein) or both
- make inside the cell and secreted onto the cells surface
glycocalyx
a glycocalyx that is organized, uniforms, and firmly attached to the cells surface
capsule
a glycocalyx that is unorganized and only loosely attached to the cell wall
slime layer
- capsules often protect pathogenic bacteria from phagocytosis by cells of the host.
- enables the cell to survive by attaching to various surfaces in their natural environment.
- can be source of nutrition, the sugars ca be broken down and used when energy stores are low.
- a glycocalyx can also protect a cell againt dehydration
- its viscosity may inhibit the movement of nutrients out of the cell
this is called
functions of glycocalyx
These are:
- long filamentous appendage that propels the bacterial cell
- the rotation is either clockwise or counterclockwise
- motility enables bacteria to move toward a favorable environment (attractant) or away from an adverse one (repellent)
This is called:
Flagella
The ability of an organism to move by itself is called:
Motility
- an appendage on a bacterial cell used for attachment
- can number anywhere from a few to several hundred per cell
- have tendency to adhere to each other and to surfaces (liquids, glass, rocks, epithelial surfaces)
This is called:
Fimbriae
- an appendage on a bacterial cell used for conjugation
- are longer than fimbriae and number only one or 2 per cell
- are used to bring bacteria together allowing for the transfer of DNA from one cell to another
This is called:
Pili
The transfer of genetic material from one cell to another involving cell to cell contact is called:
Conjugation
- is a complex, semirigid structure that surrounds the underlying fragile plasma (cytoplasmic) membrane
- prevents the bacterial cells from rupturing by protecting the fragile cell membrane
- responsible for the shape of the cell
- point of anchorage for structures external to it (glycocalyx, flagella, fimbriae, pili)
- contributes to the ability of some bacteria (gram negative) to cause disease
- site of action of some antibiotics
- chemical composition and structure is used to differentiate major types of bacteria (gram positive, gram negative)
This is a description of:
Cell wall
These have:
- many layers of peptidoglycan
- a thick, rigid structure that also contains teichoic acids
- has no outer membrane
- resists decolorization, retains the primary stain crystal violet
- appears purple in Gram staining
- susceptible to antibiotics, detergents, lysozyme
This is a description of:
Gram positive cell walls
- one or a few layers of peptidoglycan
- no teichoic acid
- has an outer lipid membrane (lipopolysaccharides, lipoproteins)
- decolorizes and takes up the counterstain safranin
- appears pink, red in gram staining
- more resistant to antibiotics, detergents, lysozyme
This is called:
Gram negative cell walls
a thin structure lying inside the cell wall and enclosing the cytoplasm of the cell is called
plasma membrane
these functions define:
enzymes, support, channels, cell to cell recognition.
internal cell wall
substances cross the cell membrane from an area of high concentration to an area of low concentration; the cell doesnt do work, doesnt use cellular ATP energy to move substances across the cell membrane. this is called:
passive processes
the movement of glucose from a high concentration of glucose to a low concentration of glucose across a cell membrane with the help of a specific cell membrane carrier protein. this is called:
facilitated diffusion
the movement of water from a high concentration of water to a low concentration of water across a selectively permeable cell membrane that only allows he solvent water across and not the soluble. this is called
osmosis
These are:
- long filamentous appendage that propels the bacterial cell
- the rotation is either clockwise or counterclockwise
- motility enables bacteria to move toward a favorable environment (attractant) or away from an adverse one (repellent)
This is called:
Flagella
The ability of an organism to move by itself is called:
Motility
- an appendage on a bacterial cell used for attachment
- can number anywhere from a few to several hundred per cell
- have tendency to adhere to each other and to surfaces (liquids, glass, rocks, epithelial surfaces)
This is called:
Fimbriae
- an appendage on a bacterial cell used for conjugation
- are longer than fimbriae and number only one or 2 per cell
- are used to bring bacteria together allowing for the transfer of DNA from one cell to another
This is called:
Pili
The transfer of genetic material from one cell to another involving cell to cell contact is called:
Conjugation
- is a complex, semirigid structure that surrounds the underlying fragile plasma (cytoplasmic) membrane
- prevents the bacterial cells from rupturing by protecting the fragile cell membrane
- responsible for the shape of the cell
- point of anchorage for structures external to it (glycocalyx, flagella, fimbriae, pili)
- contributes to the ability of some bacteria (gram negative) to cause disease
- site of action of some antibiotics
- chemical composition and structure is used to differentiate major types of bacteria (gram positive, gram negative)
This is a description of:
Cell wall
These have:
- many layers of peptidoglycan
- a thick, rigid structure that also contains teichoic acids
- has no outer membrane
- resists decolorization, retains the primary stain crystal violet
- appears purple in Gram staining
- susceptible to antibiotics, detergents, lysozyme
This is a description of:
Gram positive cell walls
- one or a few layers of peptidoglycan
- no teichoic acid
- has an outer lipid membrane (lipopolysaccharides, lipoproteins)
- decolorizes and takes up the counterstain safranin
- appears pink, red in gram staining
- more resistant to antibiotics, detergents, lysozyme
This is called:
Gram negative cell walls
a thin structure lying inside the cell wall and enclosing the cytoplasm of the cell is called
plasma membrane
these functions define:
enzymes, support, channels, cell to cell recognition.
internal cell wall
substances cross the cell membrane from an area of high concentration to an area of low concentration; the cell doesnt do work, doesnt use cellular ATP energy to move substances across the cell membrane. this is called:
passive processes
the movement of glucose from a high concentration of glucose to a low concentration of glucose across a cell membrane with the help of a specific cell membrane carrier protein. this is called:
facilitated diffusion
the movement of water from a high concentration of water to a low concentration of water across a selectively permeable cell membrane that only allows he solvent water across and not the soluble. this is called
osmosis
