The Cell

Question 1

Active transport

Answer 1

Movement of a compound against its electrochemical gradient. Requires expenditure of energy. Can be accomplished by direct expenditure of ATP and indirectly by using ATP to create an electrochemical gradient.

Question 2

Adaptations

Answer 2

Genetic or behavioral changes that are advantageous in the given environment. Can lead to speciation.

Question 3

Adipocytes

Answer 3

Cells containing predominantly fat droplets.

Question 4

Aerobic

Answer 4

Requiring oxygen

Question 5

Allele

Answer 5

One form of a gene.

Question 6

Amphipathic

Answer 6

Having both a polar and a non polar portion.

Question 7

Anaerobic

Answer 7

Not dependent on oxygen for growth and survival.

Question 8

Apoptosis

Answer 8

Programmed cell death. Cells that are about to undergo apoptosis contain a high concentration of lysosomes. Apoptosis can contribute to development (webbed hands of human embryo).

Question 9

Archaea

Answer 9

One of two domains of prokaryotes. Have as much in common with eukaryotes as they do with bacteria. Typically found in extreme environments such as salty lakes and boiling hot springs. Cell walls not made from peptidoglycan.

Question 10

Bacilli

Answer 10

Rod-shaped bacteria. Ex: E. coli,

Question 11

Bacteria

Answer 11

One of two domains of prokaryotes. Most prokaryotes are bacteria.

Question 12

Bacterial envelope

Answer 12

Surrounds the protoplast (the bacterial plasma membrane (phospholipid bilayer) and everything it contains). The component of the envelope adjacent to the plasma membrane is the cell wall. Cell walls of bacteria are made of peptidoglycan. Gram-positive =thick peptidoglycan = appear purple after gram staining. Gram-negative =thin peptidoglycan = appear pink.

Question 13

9+2 arrangement

Answer 13

The major portion of each eukaryotic flagellum and cilium contains nine pairs of microtubules that form a circle around two lone microtubules.

Question 14

Bacteriophage

Answer 14

A virus that infects bacteria, typically injects nucleic acids into the host cell through its tail after viral enzymes have digested a hole in the cell wall.

Question 15

Binary fission

Answer 15

A type of asexual reproduction that bacteria undergo.

Question 16

Bottleneck

Answer 16

A situation in which a species may face a crisis so severe that there are few survivors, whose allelic frequencies are not representative of the original population resulting in a shift in the allelic frequencies of the population and can ultimately lead to speciation.

Question 17

Cancer

Answer 17

There are a number of checkpoints that regulate the cell cycle. Sometimes a cell acquires a mutation that allows the cell to bypass these checkpoints. Such cells can grow unchecked and develop into cancer. Two types of mutations can cause cancer: tumor repressor, deactivation of a checkpoint protein; oncogene, activation of a gene that causes the proliferation of the cell.

Question 18

Capsid

Answer 18

The protein coat of a virus that contains anywhere from one to several hundred genes in the form of DNA or RNA.

Question 19

Carrier protein

Answer 19

Proteins embedded into the cell membrane that assist molecules that are too large or too polar to passively diffuse in moving across the membrane.

Question 20

Chemical concentration gradient

Answer 20

A series of vectors pointing in the direction of lower concentration.

Question 21

Centrioles

Answer 21

Function in the production of flagella and cilia but are not necessary for microtubule production.

Question 22

Chemotaxis

Answer 22

Directed movement toward substances that will promote the survival and growth of the bacterium.

Question 23

Cilia

Answer 23

Specialized structures made from microtubules that function to move fluid causing the cell itself or nearby substances to move. cilia create a whip action that causes fluid to move laterally.

Question 24

Cleavage

Answer 24

The pinching of the cytoplasm during cytokinesis.

Question 25

Cocci

Answer 25

Spherical shape bacteria. Examples include staphylococcus and streptococcus.

Question 26

Colligative property

Answer 26

A property that is based on the number of particles present rather than the type of particle.

Question 27

Conjugation

Answer 27

A method of genetic recombination for bacteria involving the transfer of a plasmid. Plasmids are small circles of extra genomic DNA that are not essential to the survival of the bacteria that carry them. Not all bacteria with plasmids can conjugate. To initiate conjugation a bacterium must contain a conjugative plasmid that possesses the gene for the sex pilus. The sex pilus is a hollow protein tube that connects two bacteria to allow the passage of the plasmid from one to the other. The passage of DNA is always from the cell that contains the conjugative plasmid to the cell that doesn’t.

Question 28

Cytoskeleton

Answer 28

A network of filaments that determines the structure and motility of a cell. Three basic parts of the cytoskeleton are microtubules, microfilaments, and intermediate filaments.

Question 29

Desmosomes

Answer 29

A type of intercellular junction that joins two animal cells at a single point. Attach directly to the cytoskeleton of each cell. Do not prevent fluid from circulating around the sides of the cell. Found in tissues that normally experience a lot of stress due to sliding like skin or intestinal epithelium. Often accompany tight junctions.

Question 30

Differential reproduction

Answer 30

May include living beyond reproduction in order to get offspring a better chance to reproduce.

Question 31

Diffusion

Answer 31

If solutions of two solutes, X and Y, are placed on opposite sides of the same container, diffusion is the net movement of X towards Y. For solutes without an electric charge, diffusion occurs in the direction of lower concentration.

Question 32

Domain

Answer 32

The most commonly used classification system contains increasingly specific groupings in the following order: domain, kingdom, phylum, class, order, family, genus, species. There are three domains: bacteria, Archaea, and Eukarya.

Question 33

Dynein

Answer 33

A protein that makes up the cross bridges that connect each outer pair of microtubules to its neighbor in the 9+2 arrangement of flagella and cilia.

Question 34

Electrical concentration gradient

Answer 34

A series of vectors pointing in the direction that a positively charged particle will tend to move.

Question 35

Electrochemical gradient

Answer 35

The chemical concentration gradient plus the electrical concentration gradient for a specific solute.

Question 36

Endocytosis

Answer 36

A method that cells use to acquire substances from the extracellular environment. There are several types of endocytosis: phagocytosis, Pinocytosis, and receptor mediated endocytosis. Only a few specialized cells are capable of phagocytosis.

Question 37

Endoplasmic reticulum

Answer 37

Where are proteins that will ultimately be exported from the cell or sequestered in a vesicle are translated.

Question 38

Enveloped viruses

Answer 38

Viruses with viral envelopes that are pinched off pieces of host cellular membrane that form as the virus undergoes exocytosis from the cell. To a certain extent, the envelope protects and envelopes virus from detection by the immune system. Even more importantly, the receptors on the envelope allow the virus to bind to a new host cell and start the process all over again.