Cells

Question 1

Plasma membrane

Answer 1

Selective barrier that surrounds the cell

Question 2

Eukaryotic cell

Answer 2

A cell with DNA contained in a double membrane-bound nucleus

Question 3

Prokaryotic cell

Answer 3

A cell with DNA concentrated in a region called the nucleoid

Question 4

Cytoplasm

Answer 4

The contents of a cell, excluding the nucleus

Question 5

Microvilli

Answer 5

Projections that increase the surface area of a cell

Question 6

Nucleus

Answer 6

The container for most genes in a eukaryotic cell

Question 7

Chromosomes

Answer 7

Discrete units of DNA that carry genetic information

Question 8

Nucleolus

Answer 8

A structure inside the nucleus that synthesizes ribosomes

Question 9

Ribosomes

Answer 9

Complexes of rRNA and protein; synthesize proteins from RNA; can be free in the cytosol or bound to ER

Question 10

Endomembrane system

Answer 10

The multi-organelle pathway that regulates protein traffic and performs metabolism

Question 11

Endoplasmic reticulum

Answer 11

An extensive network of convoluted membranes

Question 12

Smooth ER

Answer 12

Lacks surface ribosomes; synthesizes lipids, detoxifies, stores calcium ions

Question 13

Rough ER

Answer 13

Has surface ribosomes; modifies proteins and phospholipids

Question 14

Golgi apparatus

Answer 14

Shipping center of the cell; receives at the cis face from ER, sends at the trans face to other areas

Question 15

Cisternal maturation model

Answer 15

In the Golgi, the stacks of cisternae move from the cis to the trans face

Question 16

Lysosomes

Answer 16

Membrane-bound sac of hydrolytic enzymes

Question 17

Phagocytosis

Answer 17

Cell breaking down food particles

Question 18

Autophagy

Answer 18

Cell recycling damaged components

Question 19

Vacuoles

Answer 19

Large vesicles that store materials

Question 20

Mitochondria

Answer 20

Site of cellular respiration, change fuel to energy (ATP)

Question 21

Chloroplasts

Answer 21

Site of photosynthesis, change energy to organic molecules

Question 22

Endosymbiont theory

Answer 22

An idea that early eukaryotes assimilated prokaryotes, forming a merged eukaryote with mitochondria and/or chloroplasts

Question 23

Peroxisome

Answer 23

An organelle that removes hydrogen from substrates

Question 24

Cytoskeleton

Answer 24

A network of fibers that organizes cellular structures and activities

Question 25

Microtubules

Answer 25

Thin, hollow tubes made of tubulin; includes centrioles, cilia, and flagella

Question 26

Microfilaments

Answer 26

Two intertwined strands of actin; includes myosin and cortical microfilaments

Question 27

Intermediate filaments

Answer 27

Fibrous proteins coiled into cables

Question 28

Amphipathic

Answer 28

Describing a molecule with hydrophobic and hydrophilic regions

Question 29

Fluid mosaic model

Answer 29

A description of the cell membrane as a mosaic of proteins bobbing in a fluid bilayer of phospholipids

Question 30

Cholesterol in the membrane

Answer 30

Moderates membrane fluidity to prevent breakup or solidification at extreme temperatures

Question 31

Integral proteins

Answer 31

Membrane proteins that partly or fully penetrate the hydrophobic region of the lipid bilayer

Question 32

Peripheral proteins

Answer 32

Membrane proteins that are only loosely bound to the lipid bilayer

Question 33

Six main functions

Answer 33

Transport, enzymatic activity, signal transduction, cell-cell recognition, intercellular joining, attachment to ECM/cytoskeleton

Question 34

Glycolipids

Answer 34

Lipids bonded to a membrane carbohydrate

Question 35

Glycoproteins

Answer 35

Proteins bonded to a membrane carbohydrate

Question 36

Transport proteins

Answer 36

Facilitate movement of hydrophilic substances across the membrane

Question 37

Channel proteins

Answer 37

Contain a hydrophilic channel that allows molecules to pass across

Question 38

Carrier proteins

Answer 38

Change shape to shuttle their cargo across the membrane

Question 39

Diffusion

Answer 39

"Spreading out" phenomenon due to thermal energy of atoms/molecules

Question 40

Concentration gradient

Answer 40

The "slope" of concentration, from high to low

Question 41

Passive transport

Answer 41

Cell expends zero energy

Question 42

Osmosis

Answer 42

Diffusion through a selectively permeable membrane

Question 43

Animal cell tonicity

Answer 43

Isotonic (ideal), hypertonic, hypotonic

Question 44

Plant cell tonicity

Answer 44

Turgid (ideal), flaccid, plasmolyzed

Question 45

Ion channels

Answer 45

Channel proteins for ions

Question 46

Sodium-potassium pump

Answer 46

A carrier protein that moves sodium outside the cell and potassium into the cell, both against their concentration gradients

Question 47

Membrane potential

Answer 47

The slight difference in charge outside cells compared to inside

Question 48

Cotransporters

Answer 48

Transport proteins that couple the downhill movement of one solute with the uphill movement of a second

Question 49

Exocytosis

Answer 49

Secretion of molecules out of cells

Question 50

Endocytosis

Answer 50

Taking in of outside matter by a cell

Question 51

Phagocytosis

Answer 51

Cellular eating; extension of pseudopodia around a large particle to eat

Question 52

Pinocytosis

Answer 52

Cellular drinking; intake of tiny amounts of extracellular fluid

Question 53

Receptor-mediated endocytosis

Answer 53

Pinocytosis that is triggered by ligands binding to receptors

Question 54

Paracrine signaling

Answer 54

Release of chemicals to all nearby cells

Question 55

Synaptic signaling

Answer 55

Release of neurotransmitter due to an electrical signal

Question 56

Endocrine signaling

Answer 56

Release of organism-wide hormone that only some cells respond to

Question 57

Three stages of cell signaling

Answer 57

Reception, transduction, response

Question 58

Ligand

Answer 58

A signaling molecule that binds to a specific receptor; also called first messengers

Question 59

Three types of receptors

Answer 59

Ion channel receptors, G protein-coupled receptors, tyrosine kinases

Question 60

Second messengers

Answer 60

Water soluble molecules that spread within the cell to trigger responses