Ch 1 - The Fundamental Units of Life Flashcards

1
Q

archaeon

A

microscopic organism that is a member of one of the two divisions of prokaryotes; often found in hostile environments such as hot springs or concentrated brine (see also bacterium)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

bacterium

A

microscopic organism that is a member of one of the two division of prokaryotes; some species cause disease. the term is sometimes used to refer to any prokaryotic microorganism, although the world of prokaryotes also includes archaea, which are only distantly related to each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

cell

A

the basic unit from which a living organism is made; an aqueous solution of chemicals, enclosed by a membrane, that has an ability to self-replicate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

chloroplast

A

specialized organelle in algae and plants that contains chlorophyll and serves as the site for photosynthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

chromosome

A

long, threadlike structure composed of DNA and proteins that carries the genetic information of an organism; become visible as a distinct entity when a plant or animal cell prepares to divide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

cytoplasm

A

contents of a cell that are contained within its plasma membrane but, in the case of eukaryotic cells, outside the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

cytoskeleton

A

system of protein filaments in the cytoplasm of a eukaryotic cell that gives the cell shape and the capacity for directed movement. its most abundant components are actin filaments, microtubules and intermediate filaments.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

cytosol

A

contents of the main compartment of the cytoplasm, excluding membrane-enclosed organelles such as endoplasmic reticulum and mitochondria. the cell fraction remaining after membranes, cytoskeletal components and other organelles have been removed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

DNA

A

double stranded polynucleotide formed from two separate chains of covalently linked deoxyribonucleotide units. it serves as the cell’s store of genetic information that is transmitted from generation to generation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

electron microscope

A

instrument that illuminates a specimen using beams of electrons to reveal and magnify the structures of very small objects, such as organelles and large molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

endoplasmic reticulum (ER)

A

labyrinthine membrane-enclosed compartment in the cytoplasm of eukaryotic cells where lipids and proteins are made

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

eukaryote

A

an organism whose cells have a distinct nucleus and cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

evolution

A

process of gradual modification and adaptation that occurs in living organisms over generations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

fluorescence microscope

A

instrument used to visualize a specimen that has been labeled with a fluorescent dye; samples are illuminated with a wavelength of light that excite the dye, causing it to fluoresce

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

genome

A

the total genetic information carried by all the chromosomes of a cell or organism; in humans, the total number of nucleotide pairs in the 22 autosomes plus the X and Y chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Golgi apparatus

A

membrane-enclosed organelle in eukaryotic cells that modifies the proteins and lipids made in the endoplasmic reticulum and sorts them for transport to other sites

17
Q

homologous

A

describes genes, chromosomes or any structures that are similar because of their common evolutionary origin. can also refer to similarities between protein sequences or nucleic acid sequences

18
Q

micrometer

A

unit of length equal to one millionth (10 to the power -6) of a meter

19
Q

microscope

A

instrument for viewing extremely small objects. some use a focused beam of visible light and are used to examine cells and organelles. others use a beam of electrons and can be used to examine objects as small as individual molecules.

20
Q

mitochondrion

A

membrane-enclosed organelle, about the size of a bacterium, that carries out oxidate phosphorylation and produces most of the ATP in eukaryotic cells

21
Q

model organism

A

a living thing selected for intensive study as a representative of a large group of species. examples include the mouse (representing mammals), the yeast Saccharomyces cerevisiae (representing unicellular eukaryote) and Escherichia coli (representing bacteria)

22
Q

nucleus

A

in biology, refers to the prominent, rounded structure that contains the DNA of a eukaryotic cell. in chemistry, refers to the dens, positively charged center of an atom

23
Q

organelle

A

a discrete structure or subcompartment of a eukaryotic cell that is specialized to carry out a particular function. examples include Golgi apparatus and mitochondria

24
Q

photosynthesis

A

the process by which plants, algae and some bacteria use the energy of sunlight to drive the synthesis of organic molecules from carbon dioxide and water

25
Q

plasma membrane

A

the protein-containing lipid bilayer that surrounds a living cell

26
Q

prokaryote

A

major category of living cells distinguished by the absence of a nucleus; includes the archaea and the eubacteria (commonly called bacteria)

27
Q

protein

A

macromolecule built from amino acids that provide cells with their shape and structure and performs most of their activities

28
Q

protozoan

A

a free-living, nonphotosynthetic, single-celled, motile eukaryote

29
Q

ribosome

A

large macromolecular complex, composed of RNAs and proteins, that translates a messenger RNA into a polypeptide chain

30
Q

RNA (ribonucleic acid)

A

molecule produced by the transcription of DNA; usually single-stranded, it is a polynucleotide composed of covalently linked ribonucleotide subunits. serves a variety of informational, structural, catalytic and regulatory functions in cells