Chapter 3 The Living Unit

Front 1

1. cells are the basic structural and functional units of life
2. The activity of an organism depends on the activities of its cells
3. The biochemical activities of a cell are dictated by their organelles
4. The continuity of life has a cellular basis

Back 1

Four concepts of the cell theory

Front 2

1. cells vary greatly in their size and shape
2. all cells are composed primarily of CHNO
3. all cells have the same basic parts and some common functions
4. a generalized human cell contains the plasma membrane, the cytoplasm and the nucleus

Back 2

Characteristics of cells

Front 3

composed of a double layer of phospholipids in which small amounts of cholesterol and proteins are embedded

Back 3

Plasma membrane

Front 4

composed of two layers of phospholipids lying tail to tail with their polar heads exposed to water inside and outside the cell

Back 4

Phospholipid bilayer

Front 5

Glycolipids

Back 5

only found in the outer membrane

Front 6

found only in the outer membrane, cell signaling

Back 6

Lipid rafts

Front 7

firmly inserted into the plasma membrane
span the width of the membrane and are involved with transport as channels or carriers

Back 7

Integral proteins

Front 8

Not embedded in the membrane
attached to integral proteins or to phospholipids
may function as enzymes

Back 8

Peripheral proteins

Front 9

fuzzy, sticky, carb-rich area surrounding the cell

Back 9

Glycocalyx

Front 10

type of membrane junction in which integral proteins on adjacent cells fuse together to form an impermeable junction in order to prevent molecules from passing through the extracellular space between cells.

Back 10

Tight junctions

Front 11

Mechanical couplings that are scattered along the sides of adjoining cells that prevent seperate on and reduce the chance of tearing when a tissue is stressed

Back 11

Desmosomes

Front 12

communication junction between cells that allows substances to pass between adjacent cells

Back 12

Gap junction

Front 13

use ATP to move substances down their concentration gradient

Back 13

Passive processes DO NOT

Front 14

Diffusion
Simple diffusion
Facilitated diffusion
Osmosis

Back 14

Types of passive processes

Front 15

movement of molecules down their concentration gradient

rate influenced by size of molecule and temperature

Back 15

Diffusion

Front 16

Simple diffusion

Back 16

diffusion through the plasma membrane

Front 17

substances are moved through the plasma membrane by binding to protein carriers in the membrane or by moving through channels

Back 17

Facilitated diffusion

Front 18

diffusion of water through a selectively permeable membrane

Back 18

Osmosis

Front 19

uses solute pumps to move substances across a concentration gradient

Back 19

Active transport

Front 20

Primary active transport
Secondary active transport

Back 20

Two types of active transport

Front 21

Means by which LARGE particles, macromolecules and fluids are transported across the plasma membrane, or within the cell

Back 21

Vesicular transport

Front 22

a process used to move substances from inside the cell to the extracellular enviroment

Back 22

Exocytosis

Front 23

vesicular transport processes that move molecules using protein coated vesicles

Back 23

Endocytosis
Transcytosis
Vesicular trafficking

Front 24

voltage across the cell membrane that occurs due to a seperation of oppositely charged particles

inside of membrane is negatively charged compared to outside

Back 24

Membrane potential

Front 25

determined mainly by the concentration gradient of potassium (K+)

Back 25

Resting membrane potential

Front 26

Resting membrane potential is maintained by

Back 26

Active transport pumps

Front 27

cell adhesion molecules are glycoproteins that play roles in embryonic development, wound repair, and immunity

Back 27

CAM'S

Front 28

integral proteins and glycoproteins that serve as binding sites

function in contact signaling, electrical signaling and chemical signaling

Back 28

Roles of membrane receptors

Front 29

consists of one atom of oxygen and one atom of nitrogen

first known gas to act as a biological messenger

Back 29

Nitric oxide

Front 30

cellular material between the cell membrane and the nucleus and is the site of most cellular activity

Back 30

Cytoplasm

Front 31

cytosol
cytoplasmic organelles
cytoplasmic inclusions

Back 31

Three major elements of cytoplasm

Front 32

Mitochondria
Ribosomes
Endoplasmic reticulum (smooth and rough )
Golgi apparatus
Lysosomes
Peroxisomes
Cytoskeleton
Centrosomes and centrioles

Back 32

Cytoplasmic organelles

Front 33

Mitochondria

Back 33

power plants of the cell, produces most of the ATP

Front 34

Ribosomes

Back 34

consists of protein and ribosomal RNA, the site if protein synthesis

Front 35

looping network of tubules, enzymes catalyze reactions involved in several processes

Back 35

Smooth ER

Front 36

contains Ribosomes that manufactures all proteins that are secreted from cells

Back 36

Rough ER

Front 37

series of stacked, flattened membranous sacs associated with groups of membranous vesicles

modifies, concentrates and packages proteins and lipids made at the rough ER

packages digestive enzymes into Lysosomes

Back 37

Golgi apparatus

Front 38

spherical membranous organelles that contain digestive enzymes

Back 38

Lysosomes

Front 39

membranous sacs containing enzymes such as oxidases and catalases, which are used to detoxify harmful substances, free radicals

Back 39

Peroxisomes

Front 40

series of rods running through the cytosol, supporting cellular structures and aiding in cell movement

Back 40

Cytoskeleton

Front 41

microtubules
microfillaments
intermediate filaments

Back 41

Three types of rods in cytoskeleton

Front 42

region near the nucleus in which a group of microtubules is anchored

function as a microtubule organizing center, and forms the miotic spindle during cell division

Back 42

Centrosomes

Front 43

small, barrel - shaped organelles associated with the centrosome and also form the bases of cilia and flagella

Back 43

Centrioles

Front 44

finger like extensions of the plasma membrane that increase surface area.

Back 44

Microvilli

Front 45

control center of the cell

contains cellular DNA

most cells have only one nucleus

all body cells except red blood cells have nuclei

larger than cytoplasmic organelles, it has three regions and protein-containing subcompartments

Back 45

Nucleus

Front 46

double membrane barrier surrounding the nucleus

Back 46

Nuclear envelope

Front 47

dark staining spherical bodies within the nucleus

typically one or two per nucleus

assembly site of ribosomal subunits

large in actively growing cells

Back 47

Nucleoli

Front 48

roughly half DNA, the genetic material of the cell, and half histone proteins

Nucleosomes are the fundemental unit of chromatin

when a cell is preparing to divide, chromatin condenses into dense, rod like chromosomes

Back 48

Chromatin

Front 49

Stages of Mitosis

Back 49

Prophase
Metaphase
Anaphase
Telophase

Front 50

G1 centrioles begin replicate
S DNA is replicated
G2 centrioles finish replicating, final preperation for mitosis begin

DNA material in the form of chromatin

Nuclear envelope visible

Back 50

Interphase (not part of mitosis)

Front 51

1st phase mitosis
chromatin coils and condenses forming chromosomes
nuclear envelope fragments
miotic spindle forms
chromosomes first appear duplex
chromosomal structures are attached to the kinetochore fibers

Back 51

Prophase

Front 52

molarity inside and outside cell are equal

Back 52

Isotonic

Front 53

molarity outside the cell is greater than inside, draws water in

Back 53

Hypotonic

Front 54

molarity inside cell greater than outside, water pushes out

Back 54

hypertonic

Front 55

Metaphase

Back 55

chromosomes line up in center of cell

Front 56

Shortest phase
Centromeres of chromosomes split simultaneously
each chromatid becomes a chromosome
v shaped due to pull of poles

Back 56

Anaphase

Front 57

begins when chromosome movement stops
new nuclear membrane forms around each mass
nucleoli disappears
spindle disappears

Back 57

Telophase

Front 58

begins during late Anaphase
form cleavage furrow
two daughter cells pinched apart, each containing a nucleus identical to the original

Back 58

Cytokinesis

Front 59

takes place in nucleus

Back 59

Transcription

Front 60

Initiation
Elongation
Termination

Back 60

3 Phases of transcription

Front 61

converts base sequence of nucleic acids into the amino acid sequence of proteins
involves mRNAs, tRNA's, and rRNA's

Back 61

Translation

Front 62

carries instructions for building a polypeptide, from gene in DNA to Ribosomes in cytoplasm

Back 62

mRNA

Front 63

structural component of Ribosomes that, along with tRNA, helps translate message from mRNA

Back 63

rRNA

Front 64

transfer RNA, bind to amino acids and pair with bases of codons of mRNA at ribosome to begin process of protein synthesis

Back 64

tRNA

Front 65

Involves mRNAs, tRNAs, and rRNAs

Back 65

Translation