7 th Grade Microbiology Study Guide
Answers
Vocabulary-
Flagella – long, thin, whip-like structure that helps some protists move from place to place.
Cilia – short thread-like structures that stick out from the cell membrane and help the organism move quickly in any direction.
Aerobe – an organism that uses oxygen for respiration
Anaerobe – an organism that does not use oxgen, or cannot live in an oxygenated environment.
Pathogen – an organism that causes disease.
Protist – a one-celled or many-celled eukaryotic organism that lives in moist or wet places.
Euglenoids – plant-like protists that also have characteristics of animals.
Diatoms – plant-like protists that form glasslike boxes around themselves.
Dinoflagellates – algae that produce a toxin that is harmful to humans and have two flagella that cause it to have a spinning motion.
Protozoans – one-celled, animal-like protists that live in water or soil, or on living and dead organisms.
Ascus – little saclike reproductive structures in which sac fungi produce spores.
Hyphae – many-celled, threadlike tubes that form the body of a fungus.
Mycorrizae – a network of hyphae and roots that help plants absorb more of certain nutrients from the soil.
Sporangium – round spore case of zygotic fungi
Saprophyte – organism that gets food by absorbing dead and rotting tissues of other organisms.
Concepts-
1.
Euglena- moves with a flagellum, plant-like, contains chloroplasts.
Amoeba- moves with a psuedopod, is animal-like.
Paramecium- moves with cilia, has an oral groove and both a micronucleus and a
2.
macronucleus, and is animal-like.
Animal like Plant like Fungus like
Called protozoans, do not have cell walls, move around with cilia, flagella, or pseudopods, eats other organisms
Has chlorophyll, makes own food, cell walls, and structures to hold in place
Produce spores, eat dead organisms or as parasites, can have cell walls, can often move with pseudopods
Paramecium, Amoeba Euglena, Algae Slime molds, water molds, downy mildew
3.
Archaebacteria- live in areas that have extreme temperatures and/or pressure.
Eubacteria- live everywhere else.

4.
Cocci Baccili
5.
Bacteria have to have:
Ribosomes- to make proteins
Nucleus- as a control center and to contain DNA
Cytoplasm- to suspend organelles
Cell membrane and/or cell wall- to contain everything
Spirillia
6.
Some bacteria may have a gelatin capsule, a slime layer, or a flagellum.
7.
Bacteria reproduce asexually through fission, and sexually by exchanging genetic material through thin tubes that pass through both bacteria.
8.
Some bacteria produce their own food through photosynthesis or chemical reactions, others eat other bacteria, and some eat dead material. (Producers, consumers, and recyclers).
9.
Aerobes- need oxygen for respiration and to break down food.
Anaerobes- lives in places without oxygen- often cannot survive if oxygen is present.
10.
Cyanobacteria live together in long chains. They are important because they produce oxygen in the water, but can also be harmful by taking all the nutrients in the water. They make their own food through photosynthesis, have clorophyll, and also have a blue pigment that gives them their color.
11.
Consumer bacteria are categorized by whether they test positive for Gram’s stain. Gram’s stain is absorbed by the cell wall, so the thicker cell walled bacteria are grouped together and have a purple color. Thinner walls, or bacteria that have no cell walls, are pink, and are grouped separately.
12.
Beneficial bacteria- nitrogen fixers, saprophytes, intestinal bacteria, bacteria that break down wastes, bacteria used to make dairy products and other foods.
13.
Antibiotics stop bacteria growth and harm bacteria. Penicillin prevents bacteria from forming cell walls.
14.
Saprophytic bacteria can be used for composting, water treatment, and bioremediation.

15.
Nitrogen fixing bacteria take nitrogen from the air and converts it into forms other plants and animals can use.
16.
Pathogens are harmful organisms . Toxins are harmful substances .
17.
Pasteurization is the process of heating food to a temperature that kills most bacteria, but doesn’t affect the flavor.
18.
A vaccine is made from dead bacteria or damaged particles taken from bacterial cell walls. When injected into the blood stream, it allows the white blood cells to recognize the bacteria.
19.
20.
21.
Protists reproduce asexually through cell division (mitosis) or meiosis.
Dinoflagellates have two flagella that cause the organism to spin when in motion.
The three colors of algae are green, brown, and red.
22.
Red algae live in salt water up to 20 meters deep, green algae live in fresh water, and brown algae live in cool saltwater environments, like the Pacific ocean.
23.
An algal bloom is when algae reproduce rapidly. If dinoflagellates bloom, other organisms like oysters and shellfish that eat the dinoflagellates can have a large build up of toxin that harm humans when they are eaten.
24.
Diatoms have industrial uses like road paint and filters, and also can be used in cosmetics and salve.
25.
A Paramecium has cilia, an oral groove, and two nuclei, the micronucleus and macronucleus.
26.
A pseudopod is an extension of cytoplasm that drags the organism along.
27.
Protozoans can be transferred to humans through a mosquito bite or through drinking infested water.
28.
The three types of fungus-like protists are slime molds, water molds, and downy mildew.
29.
Common characteristics of fungi include cell walls, have hyphae, break down dead material (are saprophytes) and often are immobile.
30.
Fungi reproduce through the use of spores and meiosis.
31.- 32. The three groups are sac fungi (they have an ascus), club fungi (like mushrooms) and zygotic fungi (have sporangium.

33.
A lichen is an organism made up of a fungus and either a green alga or cyanobacterium. The fungus gets food made by the alga (or cyanobacterium), and the alga (or cyanobacterium) is protected by the fungus. They are important because they are a food source for many animals, they help produce soil by breaking down rock.
34. Some fungi are beneficial because they help make food, recycle waste, and some are even antibiotics. Other fungi are harmful because they destroy crops or are parasitic.