Microbiology Chapter 7

the cell ____ is specialized to transport substances into and out of the cell

membrane

which condition is NOT optimal for survival of an anaerobic pathogen within a human host?

10% salt

what are the reasons for limited growth during the lag phase?

a period of adjustment is required numbers are often too low for accurate counting cells have not yet reached their max division rate

_____ transport requires ATP, whereas _____ transport doesn't require cell energy expenditure

active; passive

what word is used to describe organisms which can use oxygen in their cellular respiration pathways?

aerobic

an organism that prefers a pH of above 7 is referred to as a ____

alkalinophile

a ____ is any microorganism that grows best in the absence of oxygen

anaerobe

a type of antagonism where an organism produces an inhibitory compound to compete for space and nutrients is called _____

antibiosis

bacteria reproduce by ____ fission

binary

the element ___ is rep by the letter C in CHONPS

carbon

the range of temperatures for microbial growth is expressed as 3 _____ temperatures

cardinal

the diffusion of materials into a cell is largely controlled by which structure?

cell membrane

a ___-troph derives both energy and carbon from organic compounds

chemoheterotroph

what common term describes the single bacterium that gives rise to a colony?

colony forming unit

even though chemical elements are required for cellular growth, most are obtained thru chem _____ and must be broken down for use

compounds

the movement of molecules along a concentration gradient by spontaneous random motion to achieve a uniform distribution is termed ___

diffusion

any element or molecule that must be provided to an organism is called a _____ nutrient

essential

the passive movement of molecules across a membrane thru a carrier protein or protein channel is known as _____

facilitated diffusion

true or false: all cells can synthesize the 20 essential amino acids

false

true or false: microbes exist everywhere in the human body

false

the normal resident bacteria that normally inhabit the skin, GI tract, and other body sites are also referred to as normal resident ____

flora

microorganisms that are human pathogens are best described as which of the following nutritional types?

heterotrophic

in addition to carbs, proteins, and nucleic acids, microbes can utilize _____ as a source of essential nutrients

lipids

natural organic nutrients are usually the product of ?

living organisms

which bacterial phase of growth is it when the cells double every generation and far more cells are dividing than dying?

log

______ are chem substances required in large quantities by cells, such as carbon or phosphate

macronutrients

inorganic compunds

minerals, carbon dioxide, water

describe the features of active transport

movement is usually against the diffusion gradient involves membrane proteins requires ATP expenditure

the element _____ is represented by the letter N in CHONPS

nitrogen

macro nutrients in cells include carbohydrates, proteins, lipids, and _____ acids

nucleic

the best term for any chemical substance that must be provided to a cell for normal metabolism and growth

nutrient

what term is used to describe the "best" temp to support a microbe's growth?

optimal temperature

the majority of carbon compounds that a cell requires are:

organic

organisms that have the ability to adapt to wide variations in solute concentration are referred to as

osmotolerant

organisms that derive nutrients from the living hosts are called ____

parasites

_____ is a relationship b/w 2 organisms where the host is harmed and the colonizer benefits

parasitism

the engulfment of large particles or cells into vesicles within a cell is specifically called

phagocytosis

the element ____ is rep by the letter P in CHONPS

phosphorus

a ____-troph is an organism that uses the sun's light to provide the chemical energy to produce sugar for cellular respiration

photo

prior to refrigeration, salting was used to prevent microbial growth in foods by causing ____ in bacterial cells

plasmolysis

examples of organic nutrients

proteins; nucleic acids; methane; carbs

organisms that can grow slowly in cold, but have optimum temperatures above 20C are called

psychrotrophs

a ______ is a critical number of cells required to release inducer molecules in order to form a biofilm

quorum

what is NOT an important role for water in the growth and metabolism of cells

resistance of osmotic pressure

which element is rep by S in CHONPS?

sulfur

_____ is a close nutritional association b/w individuals from 2 species that may be helpful, harmful or neither to both members

symbiosis

the speed and continuous movement of atoms and molecules is largely controlled by

temperature

autotrophs are special because

they can use fairly free energy sources to make sugar

true or false: each different carrier protein can only bind and transport a certain molecule.

true

what term is used to describe the cloudiness of a broth culture?

turbidity