Chapter Two Terminology

Question 1

Define ATP

Answer 1

Adenosine Triphosphate, the primary agent that couples exergonic and endergonic reactions.

Question 2

Define Bilayer

Answer 2

A membrane with two molecular layers.

Question 3

Define Cell

Answer 3

The smallest unit with the capacity to live and reproduce.

Question 4

Define Cytoplasm

Answer 4

All parts of the cell that surround the central nuclear or nucleoid region.

Question 5

Define Cytoskeleton

Answer 5

The interconnected system of protein fibres and tubes that extends throughout the cytoplasm of an eukaryotic cell.

Question 6

Define Cytosol

Answer 6

Aqueous solution in the cytoplasm that contains ions and various organic molecules.

Question 7

Define DNA

Answer 7

Deoxyribonucleic acid. The large, double stranded, helical molecule that contains the genetic material for all living organisms.

Question 8

Define Eukaryote

Answer 8

Organism in which the DNA is enclosed in the nucleus.

Question 9

Define Flagellum

Answer 9

A long, threadlike, cellular appendage, found in both prokaryotic and eukaryotic cells, but with different structures and modes of locomotion.

Question 10

Define Gene

Answer 10

A unit containing the code for one of the protein molecules or one of its parts, or for functioning RNA molecules such as rRNA and tRNA.

Question 11

Define Hydrophobic

Answer 11

Non-polar substances that are excluded by water and other polar molecules.

Question 12

Define Illumination

Answer 12

The lighting up of a part, cavity, organ, or object for inspection.

Question 13

Define Magnification

Answer 13

The ration of an object viewed to its real size.

Question 14

Define Messenger RNA

Answer 14

mRNA. An RNA molecule that serves as a translate for protein synthesis.

Question 15

Define Microscopy

Answer 15

Technique for producing visible images of objects too small to be seen by the human eye.

Question 16

Define Nucleic Acid

Answer 16

A complex organic substance present in living cells, especially DNA or RNA, whose molecules consist of many nucleotides linked in a long chain.

Question 17

Define Nucleoid

Answer 17

The central region of the prokaryotic cell with no boundary membrane separating it from the cytoplasm, when DNA replication and RNA transcription occur.

Question 18

Define Nucleus

Answer 18

The central region of the eukaryotic cells, separated by membrane from its surrounding cytoplasm, where DNA replication and RNA transcription occur.

Question 19

Define Organelle

Answer 19

The nucleus and other specialized structures and compartments of eukaryotic cells.

Question 20

Define Pilus

Answer 20

A hair or hairlike appendage on the surface of a prokaryote.

Question 21

Define Plasma Membrane

Answer 21

The outer limit of the cytoplasm responsible for the regulation of substances moving into and out cells.

Question 22

Define Prokaryote

Answer 22

Organism in which the DNA is suspended in the cell interior without separation from other cellular components by a discrete membrane.

Question 23

Define Resolution

Answer 23

The minimum distance two points in a specimen can be separated and still be seen as two points.

Question 24

Define RNA

Answer 24

Ribonucleic acid. A polymer assembled from repeating nucleotide monomers in which the five carbon sugar is ribose. Cellular RNA are mRNA (which is translated to produce a polypeptide), tRNA (which brings an amino acid to the ribosome for assembly into a polypeptide during translation), and rRNA (which is a structural component of ribosomes). The genetic material of some viruses is RNA.

Question 25

Define Ribosomal RNA

Answer 25

rRNA. The RNA component of ribosomes.

Question 26

Define Ribosome

Answer 26

A ribonucleoprotein particle that carries out protein synthesis by translating mRNA into chains of amino acids.