Cell

Question 1

The phospholipid bilayer that surrounds all cells, regulating the passage of molecules in and out of the cell.

Answer 1

Cell Membrane

Question 2

The transport or natural drift of molecules traveling from an area of higher concentration to an area of lower concentration. Does not require outside energy from the cell

Answer 2

diffusion

Question 3

The diffusion of molecules that cannot pass through the cell membrane independently, but rather permeable protein channels embedded in the membrane. Does not require outside energy.

Answer 3

facilitated diffusion

Question 4

Process by which water naturally travels from an area of high water concentration to low water concentration

Answer 4

osmosis

Question 5

The measure of water’s tendency to move from a hypotonic solution to a hypertonic solution across a water-permeable membrane.

Answer 5

osmotic pressure

Question 6

The semipermeable lipid bilayer that forms the boundary of a cell.

Answer 6

plasma membrane

Question 7

A series of membrane bound sacs in the eukaryotic cytoplasm. It takes proteins produced by the endoplasmic reticulum and packages and secretes them to various destinations inside and outside of the cell.

Answer 7

Golgi apparatus

Question 8

A specialized cell compartment filled with enzymes at an acidic pH, used for digesting macromolecules.

Answer 8

lysosome

Question 9

The entire content of the cell outside the nucleus, including the membrane bound organelles and the cytosol.

Answer 9

cytoplasm

Question 10

In eukaryotes, the membrane that separates the nucleus and chromatin from the rest of the cell.

Answer 10

nuclear envelope

Question 11

The basic unit of compacted DNA. Consists of DNA wrapped with protein histones to form a bead-shaped package of chromatin

Answer 11

nucleosome

Question 12

A physical structure composed of a single long strand of DNA (and associated proteins), containing many genes along its length. The human genome consists of 46 chromosomes contained within the nucleus of each cell.

Answer 12

chromosome

Question 13

An organelle responsible for protein synthesis. Ribosomes are located in cytoplasm or endoplasmic reticulum.

Answer 13

ribosome

Question 14

The double membrane-bound organelles that produce most of the energy in eukaryotic cells through the process of aerobic (cellular) respiration, which generates ATP.

Answer 14

mitochondria

Question 15

A dense, spherical body inside the nucleus of a cell. Makes the RNA that is a structural component of the ribosomes.

Answer 15

nucleolus

Question 16

The large, central organelle of eukaryotes. Contains the genetic material of the cell and controls cellular activities.

Answer 16

nucleus

Question 17

A form of endocytosis during which liquids are taken into the cell through the invagination of the cell membrane.

Answer 17

pinocytosis

Question 18

The movement of molecules across a cell membrane from a region of lower concentration to a region of higher concentration. Because active transport moves molecules against the concentration gradient, the process requires energy.

Answer 18

active transport

Question 19

A specialized membrane bound structure in a cell that performs a specific function. Examples of organelles include the endoplasmic reticulum and the mitochondria.

Answer 19

organelle

Question 20

A cellular structure that plays an important role in cell replication. During prophase, the centrioles migrate to the poles of the cell and form the mitotic spindle that allows the chromosomes to be organized and split when the cell divides.

Answer 20

centriole

Question 21

A system of protein filaments found throughout the cytoplasm of eukaryotic cells, which provides structural support for the cell. It also helps with the movement of organelles within the cell. It is composed of microfilaments and microtubles.

Answer 21

cytoskeleton

Question 22

The main component of the cytoplasm. It is a grayish, gel-like liquid containing the nucleus, organelles, and cytoskeleton.

Answer 22

cytosol

Question 23

A rigid structure that surrounds the outer membrane of some cells and helps maintain their shape. In plants, it contains cellulose; in fungi it contains chitin; in prokaryotes it typically contains peptidoglycan.

Answer 23

cell wall

Question 24

The doctrine that every living organism is composed of cells and that all cells come only from other preexisting cells.

Answer 24

cell theory

Question 25

The stringy web of genetic material and histone proteins found in the nucleus of eukaryotic cells. During cell division, each strand of DNA coils to form a chromosome.

Answer 25

chromatin

Question 26

The chromosomal junction that marks the union point of two sister chromatids

Answer 26

centromere

Question 27

The prokaryotic concentration of genetic material. Unlike a eukaryotic cell, prokaryotes lack a nuclear envelope and therefore lack a true nucleus.

Answer 27

nucleoid

Question 28

The smallest unit of life, consisting of solution of organic molecules enclosed by a plasma membrane

Answer 28

cell

Question 29

The tendency in membranes for some substances to pass through more easily than others.

Answer 29

selective permeability

Question 30

Short, hairlike projections found on eukaryotic cells that can help the cell move or can sweep food particles toward the mouth

Answer 30

cilia

Question 31

Process by which liquids or small, solid partiles are taken into a cell in the form of small vesicles that are produced through the invagination of the cell membrane

Answer 31

endocytosis

Question 31

A network of membrane bound tubes and sacs in the cytoplasm. It is a major site of protein and lipid synthesis.

Answer 31

endoplasmic reticulum

Question 32

Process by which molecules are secreted from the cell. It occurs when a vesicle fuses with the cell membrane and releases its contents to the outside.

Answer 32

exocytosis

Question 33

A whiplike structure projecting from the surface of some cells and single-cell organisms; coordinated waving allows the organism to swim. Prokaryotic _____ are made of a single helical chain of flagellin proteins; eukaryotic ____ are made of multiple chains of microtubule proteins.

Answer 33

flagellum

Question 34

The theory describing the cell membrane as a dynamic structure with proteins floating, yet partially embedded, in a sea of phospholipids.

Answer 34

fluid-mosaic model

Question 35

Having an affinity for water; usually polar molecules. This is principally important in relation to the phospholipid bilayer.

Answer 35

hydrophilic

Question 36

Having a reluctance to mix with water; usually nonpolar molecules. The fatty acids that form the interior pocket between the two layers of the cell membrane are _____

Answer 36

hydrophobic

Question 37

The cytoskeletal fibers that are thinner than microtubules and bear tension in cells. Useful in retaining cell shape, enacting unicellular motility by localized contraction, and distributing nutrients through cytoplasmic streaming. Its the same as actin, the filaments used in muscle contraction.

Answer 37

microfilament

Question 38

The thick cellular fiber that can be disassembled and reassembled in eukaryotic cytoplasm. It supports the cell and are the chief components in cilia and flagella.

Answer 38

microtuble

Question 39

The transfer of a substance across a permeable membrane by process of diffusion, without the expenditure of energy.

Answer 39

passive transport

Question 40

A double layer of phospholipid molecules providing the structure of cell membranes. Formed naturally from the alignment of two lipid layers such that the hydrophobic tails point in ward toward each other, and the hydrophilic phosphate heads point outward towards the intra- and extracellular water.

Answer 40

phospholipid bilayer

Question 41

The complex formed during telophase in plant cells that results in the formation of two daughter cells separated by a new cell wall.

Answer 41

cell plate

Question 42

A lipid that stabilizes cell membrane fluidity in animal cells and also serves as a precursor to steroid synthesis.

Answer 42

cholesterol

Question 43

A complex carbohydrate that constitutes the cell wall of plants and protist molds

Answer 43

cellulose

Question 44

A type of lipid found in cell membranes. Phospholipids are made up of a single hydrophilic phosphate head and two nonpolar hydrophosbic lipid tails.

Answer 44

phospholipid

Question 45

The amount of energy it will take to break a chemical bond, equal to the amount of energy released when the bond was first formed.

Answer 45

bond energy

Question 46

A large membrane bound sac within cells such as plant cells. Larger than vesicles, the large central vacuole in plant cells serves a variety of functions such as storage of ions or metabolic by products.

Answer 46

vacuole

Question 46

In choloroplasts, the stacks of flattened sacs (thylakoids) used in photosynthesis

Answer 46

granum (plural - grana)

Question 47

The specialized and flattened sacs in chloroplasts responsible for photosynthetic activity. Some are found in stacks called "grana".

Answer 47

thylakoid

Question 48

The fluid located outside the thylakoids in a chloroplast.

Answer 48

stroma

Question 49

Folds on the inner mitochondrial membrane. It creates more surface area, increasing the productivity of cellular respiration.

Answer 49

crista (plural - cristae)

Question 50

An instrument that uses an electron beam to form clear and highly magnified images of microscopic structures. It cannot take pictures of living organisms.

Answer 50

electron microscope

Question 51

A protein embedded in cellular membranes responsible for active transport of ions across the membrane with a resultant change in membrane potential; can be tapped for cellular work. In animals, this is a sodium-potassium pump and in plants, bacteria and fungi, a proton pump.

Answer 51

electrogenic pump

Question 52

Temporary cytoplasmic protrusions of ameboid cells that function in movement and food uptake by phagocytosis.

Answer 52

pseudopods

Question 53

A family of closely related plant organelles including chloroplasts used in photosynthesis and amyloplasts used in starch storage.

Answer 53

plastid

Question 54

The often lethal shearing of a plasma membrane away from its cell wall due to immersion in a hypertonic solution and subsequent cell shriveling.

Answer 54

plasmolysis

Question 55

In plants, the small junctions in cell walls that allow for cytoplasmic connection between cells.

Answer 55

plasmodesma/plasmodesmata

Question 56

A form of endocytosis in which a cell ingests a solid particle.

Answer 56

phagocytosis

Question 57

The specialized cellular compartment used to break down macromolecules. Contains enzymes that transfer hydrogen from a substance to oxygen, creating hydrogen peroxide (H202). It also contains enzymes that break down the toxic hydrogen peroxide into water.

Answer 57

peroxisome

Question 58

The charge difference between inside and outside of a cell due to ion concentrations. It affects the movement of charged substances across the membrane. Electrogenic pumps (sodium-potassium and proton pumps) can alter membrane potential to do cellular work.

Answer 58

membrane potential

Question 59

Dutch clothing salesman (1632-1723) who made the first observations of bacteria and protozoa using single lens microscopes of his own design

Answer 59

van Leeuwenhoek, Antonie

Question 60

An organelle often found in protozoa that pumps excess water out of the cell to keep the cell from bursting in a hypotonic environment (like freshwater).

Answer 60

contractile vacuole

Question 61

A double membrane bound organelle that contains chlorophyll and is found in plant cells. Chloroplasts are responsible for mediating photosynthesis.

Answer 61

chloroplast

Question 61

A pigment located within a chloroplast that absorbs light in plant cells, helping to convert light energy into chemical energy through the process of phtosynthesis.

Answer 61

chlorophyll