micro-organisms Flashcards
why do some scientists classify viruses as living organisms?
because they can replicate and adapt to their environment
what is the meaning of organic matter?
a substance made by a living organism
why are viruses considered non living?
because they don’t have cells/organelles, are only made up of DNA or RNA with capsids, need to invade a host cell to reproduce, do not respond to stimuli, do not grow, do not obtain or use energy, do not complete all seven life processes
why can’t viruses reproduce?
don’t have the tools to replicate their DNA/genetic material
what is a capsid?
protein coat/shell
what are decomposers?
microorganisms that feed on remains of other animals, digest dead matter and put the nutrients into the soil, work as fertilizers
example or harmful decay?
food decay (rotting of food)
what is pasteurization?
heat treatment that destroys pathogenic microorganisms in certain foods and beverages without changing their flavor
what factors speed up the growth of microorganisms?
warmth/high temp, water, oxygen
what factors slow the growth of microorganisms?
cold temp, avoid moisture, avoid air (oxygen)
order of making yogurt or cheese?
milk–> cream–> yogurt–>cheese
what changes milk into cheese or yogurt?
bacteria
what is fermentation?
the process of turning carbohydrates (sugars) into acids or alcohol
fermentation with bacteria?
bacteria feeds on sugars in milk and change it into lactic acid (a weak, sour acid)
fermentation with fungi?
yeast (a fungi) feeds on sugar in the flour, respire and produce carbon dioxide gas, produces bubbles that make the dough rise
fermentation occurs in…
bacteria & fungi
infectious diseases?
some microbes enter your body, make you ill and reproduce in the host cell. the produce toxins that can damage your cells. they are contagious.
what is spontaneous generation?
the idea that micro-organisms spawn in the substances they are found in
who is Luis Pasteur
a French scientist in the 19th century that proved the idea of spontaneous generation to be wrong
