Chapter 3 - Test 1 Flashcards
Bacillus?
A cell that is cylindrical, rod shaped (can be blocky, round ended, spindle shaped, club shaped, drum stick shaped, short and fat, long and skinny, blunt or pointy)
Coccobacillus?
A cell that’s cylindrical, but also short and plump
Phenotype?
The traits created by the expression of the genotype (not all phenotype are turned on)
Peptidoglycan?
A unique macromolecule that provides bacteria with their relatively rigid quality.
Spirochete?
Corkscrew/spiral shaped bacteria. (Characteristic of the organism Treponema - which causes syphilis)
Genotype?
The sum of all of these types of genes constitutes an organism distinctive genetic makeup
Serotype?
Representatives of a species that stimulate a distinct pattern of antibody responses in their hosts, because of distinct surface molecules.
Endospore?
Dormant body formed within some bacteria that allows for their survival in adverse conditions
Vibrio?
Single occurring rods that are gently curved. Ex: vibrio cholerae
Tetrads?
Cells in groups of 4 - division in 2 perpendicular lines
Strain or type?
A set of descendants cloned from a common ancestor that retains the original characteristics. Any deviation from original is a different strain.
Coccus?
A cell that is ball shaped (circles, kinda squishy guys, all sorts of variation between a circle and oval) ex: deinococcus
Pleomorphic?
When a single cell type varies in some extent in shape and size. Ex: corynebacterium diphtheriae
Capsule?
A tightly fitted layer external to the cell wall
Glycocalyx?
A coating layer of molecules external to the cell wall. It serves protective, adhesive, and receptor functions. It may fit tightly (capsule) or be very loose and diffuse (slime layer)
What type of ribosomes do bacteria have?
What type of ribosomes do eukaryotes have?
What type of ribosomes do we have in our mitochondria?
70S
80S
70S
What does it mean to say that bacteria are ubiquitous?
That they are found everywhere.
What is the biological and medical significance of flagella?
Flagella can detect and move in response to chemical signals. They move towards a positive stimuli and repel from harmful chemicals.
Plasmids?
Double stranded DNA circle containing extra genes
Which clinically important bacteria produce endospores? KNOW THIS!!
Gram positive / Clostridium difficile (C diff.)
Why are bacteria endospores so difficult to destroy?
They are capable of withstanding extremes in heat, drying, freezing, radiation, and chemicals that would readily kill vegetative cells.
What are some health implications of endospores being so difficult to destroy?
They are harder to treat, and they can sneak by regular cleaning methods such as boiling water, soaps, and disinfectants.
Name at least three ways that bacteria are grouped below the species level.
- Do not exhibit a typical mode of sexual reproduction. 2. Can accept genetic information from unrelated forms, and they can alter their genetic makeup by a variety of mechanisms. 3. Members of a bacterial species should also share at least 70-80% of their genes.
What is the structure of the bacterial ribosome and how is this different from ours?
-It comes from (mostly) a single circular strand of DNA. -Has no nuclear membrane enclosure, it takes place in the nucleoid.
Pili?
Long, tubular structures made of pilin protein produced by gram negative bacteria and used for conjugation.
Fimbria?
A short, numerous-surface appendage on some bacteria that provides adhesion but not locomotion(moving from place to place).
What happens to a cell that has its Peptidoglycan removed or interfered with by antibiotics?
The cell would rupture or be disintegrated.
Compare the composition and role of the bacterial chromosome and plasmids.
???? Working on it
A. What are the functions of cell membrane in bacteria?
B. How is this different than where respiration and ATP occur in our cells?
C. What is the origin of mitochondria?
A. Regulate transport, site of functions such as: 1. Energy reactions. 2. Nutrient processing. 3. Synthesis
B. The take place in our mitochondria
C. Bacteria have no mitochondria
Why does the genetic structure of bacteria make them such great subjects for genetic engineering?
Because they can readily be manipulated in the laboratory and transferred from one bacterial cell to another.
What medically important bacteria lack a cell wall? What keeps their cell membrane rigid?
Mycoplasma pneumoniae. It is stabilized by sterols.
What functions does the lipopolysaccharide (LPS) layer serve?
The polysaccharide chains extend off surface as signaling molecules and receptors. The lipid portion is an endotoxins and stimulates fever and shock reactions.
What function does peptidoglycan serve?
It provides a strong structure framework for cell.
What is the gram stain?
??
How does the gram stain relate to the biological structure of the cell wall and membrane?
????
Compare the cell envelope of gram+ and gram- bacteria.
Gram (+) has 2 layers in cell envelope, with thicker Peptidoglycan.
Gram (-) has 3 layers in cell envelope, with thinner Peptidoglycan and outer membrane layer.
