Lecture 3- Flashcards
True or False. The cell membrane is completely made up of fats
False, it is 50% fats and 50% proteins
Why is it important to maintain membrane fluidity?
Because if it is too rigid then it won’t work correctly and if it is too fluid it will pop
What functions do cell membrane proteins have?
- Structural Support
- Detecting nutrients
- Secretion and communication
- Ion transport and energy storage
What are the 2 main ways that things can get across the cell membrane?
- Passive Transport -> moving ALONG the gradient
- Active Transport -> moving AGAINST the gradient
How is Cotransport different than Coupling?
- Cotransport -> is transporting another molecule with the original molecule
- Coupling -> is transport that uses energy from another mechanism to move molecule against its gradient
What lipid gives the ends of bacteria the rounded shape?
Cardiolipin
Fill in the blank. The more ____ in the membrane lipids then the more _____ it is.
-Kinks, fluid
What type of structures cause the membrane to become more ridged?
Cyclic Structures in the membrane lipids
True or False. A bacteria in a really hot environment would have more unsaturated lipids in its membrane.
False, it would have more SATURATED
How are Archaea lipids different than bacteria?
- The fatty acids and glycerol are connected via ETHER
- Terpenoids have a methyl branch every 4th carbon
- Bilayers can fuse to become one layer
- Terpenoids can cyclize into cyclopentane rings
What is the purpose of the cell wall?
a) Nothing
b) Protection from other bacteria
c) Protection from osmotic pressure
d) Structural support
e) Two of the above
E, both c and d
What is the cell wall made up of?
Peptidoglycan (N-acetylglucosamine and N-acetylmuramic acid) with protein cross bridges between 3rd and 4th amino acid
How does Penicillin damage the formation of the cell wall?
The drug blocks the formation of protein cross bridges by not allowing Alanine to release
How does Vancomycin damage the formation of the cell wall?
The drug blocks the formation of protein cross bridges by binding 2 Alanines together
True or False. The cell wall is the same in all microbes.
False, Bacteria can have 2 different types cell wall thickness (Gram positive & Gram Negative) and Mycobacteria have multilayered cell walls
Why does Gram positive bacteria keep the purple stain?
Because of the teichoic acid present in the cell wall. The negative charge from the acid attracts the positively charged stain
Fill in the Blanks. ________ bacteria has _______ to help contain the shape as well as _______ osmotic stress
-Gram Positive, S-layer, prevent
What defense mechanism does Gram Negative bacteria have?
- Outer membrane (This is where toxins are stored/ produced)
- Lipopolysaccharides (LPS)
- Porins - Inner membrane
- Lipoprotein
True or False. The nucleoid is stay only in one area
False, the nucleoid can extend into the cytoplasm
In bacteria, Transcription and Translation are…
a) separate
b) coupled
c) doesn’t happen
B
What is transertion?
It is the translating, transcription and membrane insertion of a protein on the cell membrane
True or False. Bacteria do NOT age
False, each pole of the bacteria are chemically different and therefore are different ages
How many replisomes are present during binary fission?
2
What is the purpose of FTS-Z
To initiate cell division by forming a ring
What microbes have thylakoids?
-Algae and Bacteria (Cyanobacteria)
What microbes have carboxysomes?
-Bacteria
What is the purpose of Gas vesicles that are seen in some photosynthesis microbes?
Helps them increase their buoyancy and stay where the light is
What type of microbes use pili?
Bacteria and Archaea
