Bios 2210 Exam 1 study guide

What is a protist?

Eukaryote that cannot be classified as an animal, plant, fungi, or bacteria

What are the Enterobacteriacea?

a group of short, Gram-negative, facultative anaerobic rods that are found in the intestinal tract of various mammals, including human

What are phototrophic bacteria?

acquire the energy for anabolism by absorbing light with pigments located in thylakoids

What is a micrograph or microphotograph?

a photograph or digital image taken through a microscope or similar device to show a magnified image of an object

What is a protozoan?

a single-celled microscopic animal of a group of phyla of the kingdom Protista, such as an amoeba, flagellate, ciliate, or sporozoan.

What is a hydrogen bond?

a weak bond between two partially charged atoms

What is selective permeability?

ability of a membrane to regulate passage of materials into and out of the cell

What molecular structure was discovered in the 1950s and who was involved? What is the field of study called molecular biology?

double helix: James watson and Francis crick.. genetics

Where are microbes?

everywhere

How are disaccharides held together?

glycosidic bonds

cell arrangement

grouping of individual cells

What is a fatty acid?

hydrocarbon chain with a carboxyl group at one end

What are fungi? And molds? Are they photosynthetic? Are they eukaryotes?

organisms that eats organic material, Molds are microscopic fungi that live on plant or animal matter, no, eukaryotic

Why does a cell "shrink" when the medium or solution it is in has a higher solute concentration than the cell itself? What is this called?

osmosis, changing concentrain

What are helminths?

parasitic worms

What is tonicity?

the ability of a surrounding solution to cause a cell to gain or lose water

What is biochemistry

the application of chemistry to the study of biological processes at the cellular and molecular level

Microbiota?

the term for the microbes that are normally present in and on the human body; usually beneficial

Describe the unique cell characteristics of Archaea.

their ability to live in extremely hot or chemically aggressive environments

What is a redox reaction?

transfer of one or more electrons from one reactant to another

What does the term strepto- mean?

twisted chain

Are Bacteria and Archaea both prokaryotes?

yes

Are Lactobacillus spp. And Streptococcus spp. Gram positive?

yes

Are bacteria found in air, soil, and water?

yes

Is glucose a monosaccharide? How many carbons does it have?

yes, 6 carbons

Typical size of bacteria

1-5 micrometers um

Typical size of virus?

10-100 nanometers

Give an example of a slightly acidic pH?

6

What is a prokaryote?

A cell without a nucleus

What is a polar covalent bond?

A covalent bond in which electrons are not shared equally

polymer

A long molecule consisting of many similar or identical monomers linked together.

What are the types and main groups of microbes?

Viruses, Bacteria, Archaea, Fungi, and Protists.

Describe Proteobacteria in terms of their cell wall srtucutre?

All "Proteobacteria" are Gram-negative (though some may stain Gram-positive or Gram-variable in practice), with an outer membrane mainly composed of lipopolysaccharides. Many move about using flagella, but some are nonmotile or rely on bacterial gliding.

Prokaryotic

An organism whose cells do not have an enclosed nucleus, such as bacteria.

endosymbiotic theory

Ancestors of mitochondria and plastids was prokaryotes that came to live in a host cell.

Microbes

Any microscopic organism. Mainly bacteria, protists, some fungi, and even some tiny multi-cellular organisms.

Eukaryotic

Cell with a nucleus (surrounded by its own membrane) and other internal organelles.

binomial nomenclature

Classification system in which each species is assigned a two-part scientific name

What is gram staining?

Gram staining is a procedure by which bacteria can be classified by the ability of the cell wall to absorb a crystal violet dye, followed by a red safranin counterstain.

Gram positive bacteria, why do they stain dark purple and how are they different from Gram negative bacteria?

Gram-positive bacteria have a thick mesh-like cell wall made of peptidoglycan (50-90% of cell envelope), and as a result are stained purple by crystal violet, whereas gram-negative bacteria have a thinner layer (10% of cell envelope), so do not retain the purple stain and are counter-stained pink by safranin.

Do any eukaryotes have cell walls?

In eukaryotes, vertebrates don't have a cell wall but plants do.

How do microscopes work?

Most microscopes use lenses to magnify the image of an object by focusing light or electrons

What was discovered in 1940s that changed the practice of medicine? Who was well known for this discovery?

Penicillian: Alexander Fleming

What are flatworms?

Platyhelminthes

What is the difference between SEM and TEM ?

SEMs are used to examine the surface of specimens and produce a 3D image. TEMs are used to examine the internal ultrastructure of cells.

What is cell morphology?

The cell shape, arrangement, structures (ex. Endospores, flagella, etc.)

phlogeny

The evolutionary history of a species or group of related species

How are the cell structures different in prokaryotes vs. eukaryotes?

The primary distinction between these two types of organisms is that eukaryotic cells have a membrane-bound nucleus and prokaryotic cells do not

Taxonomy

The scientific study of how living things are classified

Describe the shape and arrangement of the cells of Staphylococcus aureus.

They grow in clusters, pairs and occasionally in short chains.

Microbiome?

all of the microorganisms that live in a particular environment, such as a human body

What is the subunit of proteins?

amino acids

Define magnification and how to calculate total magnification when using a compound microscope ( like you would use in lab )

amount or degree of visual enlargement of an observed object : 2x,4x,10x times original 10

Define virus, are they prokaryotes or eukaryotes, why not?

an infective agent that typically consists of a nucleic acid molecule in a protein coat, is too small to be seen by light microscopy, and is able to multiply only within the living cells of a host. neither not living

What are the main groups of eukaryotes?

animals, plants, fungi, protists

What is the important role of Streptomyces?

antibiotics

What is yeast?

any unicellular fungus that reproduces vegetatively by budding or fission, including forms such as candida that can cause disease.

Colonial morphology?

appearance of colonial growth on agar media such as color, density, consistency, surface texture, shape, and size.

Why do we know much less about Archaea species when compared to Bacteria species?

archaea are less abundant and harder to find

What are some shapes of bacteria ?

bacillus (rod) coccus (spherical) spirillum (spiral) vibrio (curved rod)

How are microbes classified?

basis of cell structure, cellular metabolism, or on differences in cell components such as DNA, fatty acids, pigments, antigens, and quinones

What is a peptide bond?

bond between two amino acids

cellular & acellular

cellular is of, relating to, consisting of, or resembling a cell or cells while acellular is not composed of cells; not cellular

What is the function of proteins in the cell?

cellular machines for cellular signaling, catalyzing chemicals, molecular transportation

Modern day tree of life- Woese and Fox....and what is 16S rRNA?

cellular morphology and genomic similarities (16srRNA used)

What is electron microscopy?

it provides detailed images of cells and its parts. Electrons are absorbed, deflected or transmitted on the density of the structures of the specimen

Cholesterol, found in animal tissues, where in human cells?

liver

What cell structures are found in eukaryotic cells and not prokaryotic cells?

mitochondria

Endosymbiotic theory and its supporting evidence?

mitochoondria

organic molecules

molecules that contain carbon

What is chemotaxis?

movement of a motile cell or organism, or part of one, in a direction corresponding to a gradient of increasing or decreasing concentration of a particular substance.

Cyanobacteria? Are they eukaryotic or prokaryotic?

prokaryotic

Where are proteins made in the cell?

ribosomes

What are nematodes?

roundworms

Compare the magnification capability of SEM vs Compound light microscopy like bright field.

sem 100,000x, light 1000x

Can you recognize images taken from an SEM compared to a TEM?

sem looks 3d, tem looks 2d

What are examples of polysaccharides?

starch, glycogen, cellulose, chitin