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79 Cards in this Set

  • Front
  • Back
Many biologists do not consider viruses to be a
living organism
It is only when the virus invades a _____ ______ that it shows signs of _____.
Living cell; life
Once viruses invade living cells they can cause _________-
the word "virus" is the latin word for
List 9 diseases that are caused by viruses
influenza, AIDS, colds, West Nile, mumps, chicken pox, small pox, rabies, measles
The viruses which cause diseases are called ______ viruses
A virus does not have a ___, but it described as being a _____.
cell; particle
A virus has no ______, no _____, and is not surrounded by a _____---
nucleus, cytoplasm, membrane
Most viruses require and ____ _____ to be seen.
electron microscope
Viruses are measured in
A virus is one ______ of a ______
millionth, millimeter
The simplest viruses are a core of _____ _________ wrapped in a ____ ____
nucleic acid; protein coat
Sometimes nucleic acid is _ _ _ and sometimes it is _ _ _
The living cell which is invaded by a virus is called the ____ ___
host cell
A virus cannot _____ on its own
In the living cell, the virus injects its ____ or ________ into the host cells _____. This causes the host cell to become a ___ ____.
nucelus; viral factory
Viruses generally invade only ____ kinds of cells
The polio virus would attack only ___ ___ in the ____ ____ and ______
nerve cells; spinal cord; brain
The mumps virus infects only __ __ of ___ ___.
one pair; salivary glands
Viruses may be the primary cause of
Since viruses do not have a ____ ____ the best that can be done is to create drugs such as __ __ __ that will slow the ____ of the virus
cell membrane; AZT; reproduction
Viral diseases can be ____ with ____
prevented; vaccines
List 7 viral diseases for which there are vaccines
rabies, mumps, polio, measles, chicken pox, small pox, flu
The virus which causes the commom cold _____ so quickly and so often that there is no eddective ___ for the common cold
mutates; vaccine
When a virus enters the human body and gets into the ___ ___, the ____ ___ goes into action.
blood stream; immune system
Armed w/a _____ of the invader, these WBC go to the ____ ____ and tell it to make ___ ___ ___ which will ____ the invader. In about _ days, the ____ releases the new ___ ___ ___ which ears the birus through the process called _______
description; thymus gland; WBC; kill; 2; thymus; WBC; phagocytosis
IF you have already had the disease caused by a virus, or if you have been ____ against that disease, you already have the ___ ___ ___ which ____ the virus
vaccinated; WBC; kill
You cannot have most viral illnesses ____
There are an estimated _________ mutant forms of the virus that creates the ____ ____. IF you had had a cold fromm all of these, you would be ____ to it.
common cold; immune
____ maybe had been the first form of life to exist on earth
Early bacteria may have taken their energy from ____, ___-, and ___ rather than the ____
iron, sulfur, N2, sun
Bacteria are ____- a word which means they are everywhere
Bacteria are measured by the ________
Bacterua rabge in size from __ to____ millimicrons in length
500; 10,000
___________ are sphere shaped bacterial cells
____ are sperical bacterial cells joined in pairs
_________ are spherical shaped bacterial cells which form colonies in clusters like a cluster of _____
______ are spherical shaped bacterial cells which form colonies of filaments or a ____ of cells
Streptococcus; string
______ are rod shaped bacteria
____ are rod shaped bacteria in colonies of pairs
_____ are rod shaped bacteria joined end to end to forma a colony which resembles a string or a _____
streptobacillus; fillament
______ are cells shaped like bent rods or corkscrews
bacteria have a ___ ___ which gives it shape
cell wall
Within the bacterial cell wall there is a thin ____ ____ which surrounds the ____
plasma membrane; cytoplasm
Bacteria have no ____ ___ but a nuclear area near the______ of the cell
nuclear membrance

surrounding the bacterial cell wall is a ____ ____ which _____ the bacteria and helps the cell ____ on to things
slime layer; protects; stick
The slime layer is sometimes called a ______
Some bacteria can ____. Movement is referred to scientifically as _____.; Most of bacteria that are this move by way of _____. Those are ___ ___ structures that whips about allowing the bacterium to move in the ____.
move; motility; flagella; whip-like; fluids
Many bacteria have the ability to go ____ when temp, moisture, light conditions, and food supply do not allow them to ____ live. These bacteria transform themselves into ____ which are capable of remaining dormant for ___ of years. When conditions become right for living, they spring back to ___living.
dormany; actively; endospores; thousands; active
endospores have been found in deep layers of ____ in the antartic, trapped there for ____ of years. when placed in a better invironment, they became ___ cells.
ice, thousands, viable
Most bacteria grow best in the
Many bacteria are killed by the ____ radiation of the ___
ultraviolent, sun
Some bacteria are ____ and use oxygen for respiration
Most bacteria are ____ and are killed by oxygen
Still other bacteria can either ___ or ___ oxygen, but do best either ___ or ___ oxygen
take, leave, with, without
Those bacteria which must have oxygen are called ____ ___
obligate aerobes
Those bacteria which are killed by oxygen are called _____
obligate anaerobes
Those bacteria whih grow best w/o ocygen, but are not killed by it are called ____ ____
faculative anaerobes
Those bacteria that grow best w/oxygen, but are not killed by a lack of it are called ______ _____
faculative aerobes
The anaerobic respiration of bacteria can produce several different ___ _______ such as ___, ___ ___, and___
by-products; ethanol, lactic acid, methanol
Some bacteria are ____ and make their own food
Some bacteria have ____ for photosynthesis
Some backteria use iron, nitrogen, or sulfur and make their food through ______
Most bacteria are _____ and feed on other organisms
Some _____ bacteria are saprophytes
____ feed on dead organic matter
When saprophytes feed on dead matter, they cause this dead organic matter to _____. These bacteria also feed on dead organic matter which is intended to be ___ ___
decompose; human food
Some heterotrophic bacteria are ____.
parasites invade the bodies of ___ and ___ and get food directly from the ____ ____ of these organisms. The organism invaded by these bacteria is called the ____.
plants and animals; living tissue; host
Most bacteria reproduce by ____ ____. In ____ ___ everything in the cell is ____ and then the cell ____ into ___ cells.
binary fission; duplicated, splits, 2
Bacteria fix ____ so that plants can use it. Although 70% of the earth's atmosphere is ____, it is not in a ____ form. Bacteria transform ____ into a _____ form.
n2, n2, useable, n2, useable
Bacteria are the main _______. If there were no bacteria, dead bodies would lie around for thousands of years _____.
decomposers, unchanged
In the late 1800's, _____ _____ formulated ____ theory, which changed the course of ____ ____. ___ theory is that bacteria can cause disease.
Louis Pasteur, germ, modern medicine, germ
List 9 diseases caused by bacteria
plague, pnuemonia, whooping cough, strep throat, botulism, syphillis, salmonella, TB, leprosy
____ drugs come directly from bacteria and molds
____ drugs are synthetic versions of the chemicals that kill bacteria
The primary defense against bacterial invasion is the ____ ____
immune system
_____ is a process of heating certain liquid food , like ___, to kill most of the bacteria
pasteurization, milk
_____ prevents bacterial invasion, as does ____, ____, and _____.
Canning, refrigeration, freezing, dehydration