Microbiology module Flashcards
cell membrane
- the thin, outermost structure of human cells
- selectively permeable (it lets some substances in and out but blocks the passage of others)
- in bacterial cells, the cell membrane lies within the cell wall
cell wall
- outermost layer of the cell that maintains its shape and protects it
- human cells do not have a cell wall, but bacterial cells do (either gram-positive or gram-negative)
- a specific antibiotic targets bacteria according to its cell-wall structure but does not damage human cells because they do not contain cell walls
nucleus
- a round structure that is inside the cell
- the largest organelle
- controls the cell’s functions
- contains chromosomes (thread-like structures made of the person’s deoxyribonucleic acid (DNA), the compound that contains the body’s genetic information)
nuclear membrane
- the structure that surrounds the nucleus
- contains pores that allow larger compounds to move in and out of the cell’s nucleus
cytoplasm
- contains other organelles such as mitochondria (performs functions of the cell)
- components of cytoplasm are water, protein, ions, and nutrients
ribosome
- an organelle that contributes to protein synthesis, which is the building of proteins from their basic components, the amino acids
- support the protein chains as ribonucleic acid (RNA) builds them
endoplasmic reticulum
- provides networks of passageways for moving various substances within the cytoplasm
- where it has ribosomes on its surface area, it is the rough endoplasmic reticulum, otherwise it is the smooth endoplasmic reticulum
mitochondrion
- an organelle that gives the cells energy
- cells may have one or more mitochondria depending on how much energy the particular cell ceeds to perform its specific functions
lysosome
- function: digestion
centriole
- cylindrical-shaped organelle that plays a role in cell division
- each pair in the cell makes sure chromosomes are equally divided to the cells that result from the reproduction process
golgi apparatus
- synthesizes carbohydrates and sorts the proteins the ribosome is supporting
- has some storage functions prior to preparing some substances for removal from the cells
peroxisome
- an organelle in the cytoplasm that contains enzymes (a chemical substance in animals and plants that causes or facilitates natural processes such as digestion)
flagellum
- a tail-like appendage that allows the cell to move in a swimming-like motion
- sperm cells have flagella to help it move toward egg cells
cilia
- hair-like projections that help move substances through various tracts and paths in the body
- some mucous membranes, such as those in the respiratory tracts, have cilia
what are the different bacterial shapes?
- coccus (round
- spirillum (spiral-shaped)
- vibrio (shaped like a comma)
- bacillus (rod-shaped)
what are the two different bacterium called whenever they live with or without oxygen?
- aerobic and anaerobic
what drug kills bacteria? what has come with the overuse of these drugs?
- antibiotics
- some bacteria have developed resistance to antibiotics and are now difficult to kill
what is the specific naming convention of bacteria and some other pathogens?
- the first word conveys the microorganism’s genus (which is a biologic classification between the family and the species)
- the second word is its species
why is it sometimes difficult to grow or test viruses?
- because viruses require living tissue to survive and grow (they’re actually parasites)
what are single-celled fungi called?
yeasts
what do multi-celled fungi varieties produce?
- they are spore-producing molds
what kind of infection is athlete’s foot and a vaginal yeast infection?
- superficial fungal infection
what is a useful function that fungus has?
- they are a source of antibiotics
what is a protozoon?
- a single-celled parasite that can be microscopic or large enough to see without a microscope (in the protozoa family)
what are examples of multicellular parasites?
- lice, bed bugs, scabies, and pinworms
what term describes the usual environment of microorganisms in the human body?
- normal flora
- infection can result when the microorganisms overgrow for various reasons
what is the chain of infection?
- infectious agent
- reservoir host
- portal of exit
- mode of transmission
- portal of entry
- susceptible host
what intervention breaks the chain of infection at its first link?
hand hygiene
what are enteric pathogens?
- within or by way of the gastrointestinal tract
