Test 1 Review Terms

Question 1

Microbe

Answer 1

The term microbe was coined to refer collectively to the microscopic organisms; including bacteria; fungi; protozoa; and viruses.

Question 2

Thermophile

Answer 2

archaebacteria that live in hot springs in boiling water up to 210 degreez f

Question 3

Halophile

Answer 3

archaebacteria living in extremely salty enviornments such as the ocean and even in solid salt crystals

Question 4

Methanogen

Answer 4

methanogens are present in the gut of several organisms like cows and buffaloes and they are responsible for the procution of bio gas.

Question 5

Algae

Answer 5

A group of aquatic; photosynthetic; eukaryotic organisms ranging from unicellular to multicellular forms; and generally possess chlorophyll but lack true roots; stems and leaves characteristic of terrestrial plants.

Question 6

Protozoa

Answer 6

Eukaryotic organisms belonging to a group characterized for being single-celled; most of them motile and heterotrophic.

Question 7

Fungi

Answer 7

a general term used to denote a group of eukaryotic protists; including mushrooms; yeasts; rusts; moulds; smuts; etc.; which are characterised by the absence of chlorophyll and by the presence of a rigid cell wall composed of chitin; mannans and sometimes cellulose.

Question 8

Helminth

Answer 8

Any of the parasitic worms that live inside their host.

Question 9

Agent

Answer 9

Any power; principle or substance capable of producing an effect; whether physical; chemical or biological.

Question 10

Virus

Answer 10

Viruses possess both living and non-living characteristics. The unique characteristic that differentiates viruses from other organisms is the fact that they require other organisms to host themselves in order to survive; hence they are deemed obligate parasites.

Question 11

Viroid

Answer 11

Extremely small viruses of plants. Their genome is a 240-350 nucleotide circular rNA strand; extensively base paired with itself; so they resist RNAase attack.

Question 12

Prion

Answer 12

An infectious protein particle similar to a virus but lacking nucleic acid;

Question 13

Bacillus

Answer 13

a genus of bacteria of the family Bacillaceae; including large aerobic or facultatively anaerobic; spore forming; rod shaped cells; the great majority of which are gram-positive and motile.

Question 14

Coccus

Answer 14

a bacterium with a rounded or spherical shape. Any spherical or nearly spherical bacteria.Pertaining to bacterium with a round appearance.

Question 15

Objective lens

Answer 15

The lens or system of lenses in a microscope (or telescope) that is nearest to the object under examination.

Question 16

Ocular lens

Answer 16

Eyepiece of the microscope; the lens at the end of certain optical instruments (e.g. telescopes) used to view the image of an object; scene; etc.

Question 17

Magnification

Answer 17

The act or process of enlarging the physical appearance or image of something.

Question 18

Resolution

Answer 18

The detection of a target having two or more parts;

Question 19

Immunofluorescence

Answer 19

Immunofluorescence is a technique used for light microscopy with a fluorescence microscope and is used primarily on microbiological samples. This technique uses the specificity of antibodies to their antigen to target fluorescent dyes to specific biomolecule targets within a cell; and therefore allows visualisation of the distribution of the target molecule through the sample.

Question 20

Simple diffusion

Answer 20

The passive movement of molecules or particles along a concentration gradient; or from regions of higher to regions of lower concentration.

Question 21

Concentration gradient

Answer 21

the gradual difference in the concentration of solutes in a solution between two regions. In biology; a gradient results from an unequal distribution of ions across the cell membrane. When this happens; solutes move along a concentration gradient. This kind of movement is called diffusion

Question 22

Facilitated diffusion

Answer 22

Transport of substances across a biological membrane from an area of higher concentration to an area of lower concentration by means of a carrier molecule. Since the substances move along the direction of their concentration gradients; energy is not required.

Question 23

Active transport

Answer 23

A kind of transport wherein ions or molecules move against a concentration gradient; which means movement in the direction opposite that of diffusion or movement from an area of lower concentration to an area of higher concentration. Hence; this process will require expenditure of energy; and the assistance of a type of protein called a carrier protein.

Question 24

Osmosis

Answer 24

Net movement of water molecules through a semipermeable membrane from an area of higher water potential to an area of lower water potential.

Question 25

Electron transport chain

Answer 25

A group of compounds that pass electron from one to another via redox reactions coupled with the transfer of proton across a membrane to create a proton gradient that drives ATP synthesis.

Question 26

Electrochemical gradient

Answer 26

Proton motive force wheree a series of rotein complexes within the memhrane ejects protons from the cell.

Question 27

Peptidoglycan

Answer 27

A polymer that serves a structural role in the bacterial cell wall; giving structural strength; as well as counteracting the osmotic pressure of the cytoplasm. It is also involved in binary fission during bacterial cell reproduction. The peptidoglycan layer of Gram-positive bacteria is substantially thicker than that of Gram-negative bacteria. Hence; Gram-positive bacteria are more susceptible to certain antimicrobial agents like penicillin

Question 28

Flagellin

Answer 28

Subunit protein of the bacterial flagellum.

Question 29

Peritrichous

Answer 29

Having flagella uniformly distributed over a cell; used especially with reference to bacteria.

Question 30

Polar flagellum

Answer 30

A single flagellum at one end of the cell

Question 31

Sex pilus

Answer 31

fine filamentous projections (pili) on the surface of a bacterium that are important in conjugation. Often seem to be coded for by plasmids that confer conjugative potential on the host; in the case of the f plasmid; the f pili are 8-9nm diameter and several microns long; composed of pilin. Whether the pili merely serve to establish and maintain adhesive contact between the partners in conjugation or whether dNA is actually transferred through the central core of the pilus is still unresolved; although a simple adhesion role is more generally accepted.

Question 32

Nucleoid

Answer 32

In contrast to eukaryotes with a nucleus; prokaryotes have a nucleoid where the genetic material can be found. The nucleoid is different from the nucleus of the eukaryotes in a way that the genetic material is not enclosed in a membrane to separate it from the cytoplasm.

Question 33

Plasmid

Answer 33

A linear or circular double-stranded DNA that is capable of replicating independently of the chromosomal DNA.

Question 34

Organelle

Answer 34

Literally; the term means "little organs". As the body is composed of various organs; the cell; too; has "little organs" that perform special functions. They are membrane-bound compartments or structures of a cell.

Question 35

Exocytosis

Answer 35

The process in which the cell releases materials to the outside by discharging them as membrane-bounded vesicles passing through the cell membrane.

Question 36

Endocytosis

Answer 36

A process in which cell takes in materials from the outside by engulfing and fusing them with its plasma membrane.

Question 37

Pinocytosis

Answer 37

A process of taking in fluid together with its contents into the cell by forming narrow channels through its membrane that pinch off into vesicles; and fuse with lysosomes that hydrolyze or break down contents.

Question 38

Phagocytosis

Answer 38

The process of engulfing and ingestion of particles by the cell or a phagocyte (e.g. macrophage) to form a phagosome (or food vacuole); which in turn fuse with lysosome and become phagolysosome where the engulfed material is eventually digested or degraded and either released extracellularly via exocytosis; or released intracellularly to undergo further processing.

Question 39

Atomic number

Answer 39

The number of protons in the nucleus of an atom and also its characteristic atomic number

Question 40

Mass number

Answer 40

The mass number (A); also called atomic mass number or nucleon number; is the total number of protons and neutrons

Question 41

Isotope

Answer 41

sotopes are variants of a particular chemical element such that; while all isotopes of a given element share the same number of protons in each atom; they differ in neutron numbers

Question 42

Valence electrons

Answer 42

In chemistry; a valence electron is an electron that is associated with an atom; and that can participate in the formation of a chemical bond; in a single covalent bond; both atoms in the bond contribute one valence electron in order to form a shared pair. The presence of valence electrons can determine the element's chemical properties and whether it may bond with other elements: For a main group element; a valence electron can only be in the outermost electron shell. In a transition metal; a valence electron can also be in an inner shell.

Question 43

Hydrogen bonds

Answer 43

Weaker A hydrogen bond is the electromagnetic attractive interaction between polar molecules in which hydrogen (H) is bound to a highly electronegative atom; such as nitrogen (N); oxygen (O) or fluorine (F). The name hydrogen bond is something of a misnomer; as it is not a true bond but a particularly strong dipole-dipole attraction; and should not be confused with a covalent bond.

Question 44

Acid

Answer 44

They are chemical compounds which yield hydrogen ions or protons when dissolved in water; whose hydrogen can be replaced by metals or basic radicals; or which react with bases to form salts and water

Question 45

Base

Answer 45

The nonacid part of a salt; a substance that combines with acids to form salts; a substance that dissociates to give hydroxide ions in aqueous solutions; a substance whose molecule or ion can combine with a proton (hydrogen ion); a substance capable of donating a pair of electrons (to an acid) for the formation of a coordinate covalent bond.

Question 46

pH

Answer 46

In chemistry; pH is a measure of the acidity or basicity of an aqueous solution. Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline

Question 47

Monomer

Answer 47

A molecule that may react chemically to another molecule of the same type to form a larger molecule; such as dimer; trimer; tetramer; polymer; etc. (2) The simplest unit; or the repeating unit; of a polymer.

Question 48

Polymer

Answer 48

Polymers are made from monomers linked by chemical bonds. They are produced by polymerization; and occur either naturally or synthetically.

Question 49

Macromolecule

Answer 49

In biology; a macromolecule is a term used to contrast a micromolecule (which is smaller in size and in molecular weight). Macromolecules are usually used to refer to large biological polymers; such as nucleic acids and proteins; which are made up of small monomers linked together.

Question 50

Dehydration Synthesis

Answer 50

It is a type of condensation reaction in which monomers join together into polymers while losing water molecules. This process is carried out by losing (-OH) from one of the monomers and (H) from another monomer. The two unstable monomers join together; and the (-OH) and (H) combine forming water (H2O). A-OH + B-H ? AB + HOH

Question 51

Hydrolysis

Answer 51

The process of splitting a compound into fragments with the addition of water; a kind of reaction that is used to break down polymers into simpler units; e.g. starch into glucose.

Question 52

Denaturation

Answer 52

A process in which the folding structure of a protein is altered due to exposure to certain chemical or physical factors (e.g. heat; acid; solvents; etc.); causing the protein to become biologically inactive. Like cooking an egg white

Question 53

Active site

Answer 53

A specific region of an enzyme where a substrate binds and catalysis takes place (binding site). The part of an enzyme or antibody where the chemical reaction occurs.A structural element of protein that determines whether the protein is functional when undergoing a reaction from an enzyme. this structural element will be accordingly shaped to the structure of the enzyme at work on it.

Question 54

Substrate

Answer 54

In biochemistry; a substrate is a molecule upon which an enzyme acts. Enzymes catalyze chemical reactions involving the substrate(s). In the case of a single substrate; the substrate binds with the enzyme active site; and an enzyme-substrate complex is formed. The substrate is transformed into one or more products; which are then released from the active site. The active site is now free to accept another substrate molecule

Question 55

Proton motive force

Answer 55

energy that is generated by the transfer of protons or electrons across an energy-transducing membrane and that can be used for chemical; osmotic; or mechanical work.