Biology Campbell Chapters 6

Front 1

What is an ORGANELLE?

Back 1

Subcellular structure find in the CYTOSOL of the the cell.

Front 2

What are components of CELL THEORY?

Back 2

all organisms are made up of cells; cell is the simplest form of matter that can live; cell structure is related to function; all cells are related by their descent from earlier celss

Front 3

What are the two types of ELECTRON MICROSCOPE?

Back 3

1. SCANNING ELECTRON MICROSCOPE (SEM) - used for the detailed study of the surface of a specimen.
2. TRANSMISSION ELECTRON MICROSCOPE (TEM) - used mainly for the study of the internal structure of the cell.

Front 4

Light microscopes (LMs)

Back 4

visible light passes through a specimen and then through glasses lenses, which magnify the image

Front 5

What is CYTOLOGY?

Back 5

The study of a cell's structure

Front 6

Quality of image depends on 3 things

Back 6

magnification; resolution; contrast

Front 7

What is CELL FRACTIONATION?

Back 7

To take a cell apart and seperate the major organelles from one another. (Usually done with a centrifuge.)

Front 8

magnification

Back 8

ratio of an object's image size to its real size

Front 9

What are the basic features common to all cells?

Back 9

- All bounded by a membrane (called a PLASMA MEMBRANE)
- CYTOSOL (semifluid substance within the membrane)
- All cells have CHROMOSOMES (carrying genes in the form of DNA)
- RIBOSOMES - tiny organelles that make proteins according to instructions from the genes.

Front 10

resolution

Back 10

the measure of the clarity of the image, or the minimum distance of two distinguishable points

Front 11

What is the major difference between PROKARYOTIC and EUROKARYOTIC cells?

Back 11

Chromosomes of a eukaryotic cell are located in a membrane-enclosed organelle called the NUCLEUS.

Front 12

contrast

Back 12

visible difference in parts of the sample

Front 13

Where is DNA found in a PROKARYOTIC cell?

Back 13

Concentrated in a region called the NUCLEOID (though it is not enclosed by a membrane.

Front 14

Limits of LMs

Back 14

cannot resolve dtail finer than about .2 micrometers, resolution is limited by shortest wavelength of light used to illuminate the specimen; can magnify to about 1000 times the specimen's size; use stains/dyes to enhance specimen

Front 15

What is the NUCLEAR LAMINA?

Back 15

A netlike array of protein filaments that maintains the shape of the nucleus by mechanically supporting the nuclear envelope.

Front 16

6 LM techniques

Back 16

Brightfield stained and unstained; phase contrast; differential-interference contrast; fluorescence; confocal

Front 17

Where are CHROMOSOMES found?

Back 17

In the nucleus.
- Chromosomes carry genetic information.
- Chromosomes are made up of material called CHROMATIN (a complex of proteins and DNA).

Front 18

brightfield unstained

Back 18

light passes through specimen; image has little contrast

Front 19

What is the NUCLEOLUS?

Back 19

A prominent structure within the non-dividing nucleus; where ribosomal RNA (rRNA) is synthesized from instructions in the DNA.
- Proteins imported from the cytoplasm are assembled

Front 20

brightfield stained

Back 20

staining enhances contrast but staining means specimen is fixed/preserved/dead

Front 21

What is a RIBOSOME?

Back 21

The organelles that carry out protein synthesis; made of RNA and protein
- Free Ribosomes float free in the cytosol
- Bound Ribosomes are attached to the outside of the Endoplasmic Reticulum.

Front 22

phase contrast

Back 22

enhances contrast in unstained cells by amplifying variations in density within specimen; useful for examining living cells

Front 23

What is the difference between FREE and BOUND Ribosomes?

Back 23

Free - Most proteins made on free ribosomes function within the cytosol (eg. enzymes that catalyse the first steps of sugar breakdown.)
- Bound: generally make proteins that are desined either for insertion into membranes, for packaging within certain organelles such as lysosomes or for export from the cell (secretion).

Front 24

differential-interference contrast

Back 24

like phase contrast, but making the image appear 3D

Front 25

What is the ENDOMEMBRANE SYSTEM and what does it do?

Back 25

Different membranes that make up the Eukaryotic cell; regulates protein traffic and performs metabolic functions in the cell

Front 26

fluorescence

Back 26

tags molecules with fluorescent dyes or antibodies; substances absorb ultraviolet radiation and emits visible light

Front 27

What components of a cell are included in the ENDOMEMBRANE SYSTEM?

Back 27

Nuclear envelope; endoplasmic reticulum; Golgi apparatus; lysosomes, various kinds of vacuoles and the plasma membrane.

Front 28

confocal

Back 28

uses lasers and special optic for 'optical sectioning' of fluorescently-stained specimens

Front 29

What is the ENDOPLASMIC RETICULUM?

Back 29

A network of sacs and tubes active in membrane synthesis and metabolic processes

Front 30

electron microscopes

Back 30

achieve a resolution of about .002 nm; two types; able to study organelles; stains kill specimen

Front 31

What are two types of the ENDOPLASMIC RETICULUM?

Back 31

SMOOTH ER: so named because it's outer surface lacks ribosomes
ROUGH ER: has ribosomes that stud the outer surface of the membrane.

Front 32

Scanning electron microscopes (SEM)

Back 32

focus a beam of electrons onto the surface of a specimen, provides a 3D image; specimen usually coated with thin gold film

Front 33

What is the role of the SMOOTH ER?

Back 33

Important to the synthesis of lipids, including oils, phospholipids and steroids.
- Enzymes help detoxify drugs and poisons, especially in the liver cells.
- Stores calcium ions

Front 34

Transmission electron microscope

Back 34

focus a beam of electron through a specimen; used to study internal structures of cells; profiles a thin specimen stained with heavy metals and enhance density

Front 35

What is the role of the ROUGH ER?

Back 35

Protein secretion produced by ribosomes and moved by transport vesicles
- Also the membrane factory for the cell

Front 36

What is a GLYCOPROTEIN?

Back 36

A secretory proteins. (Have carbohydrates covalently bonded to them.)
- Found in the ER.

Front 37

all cells (prok and euk) have...

Back 37

plasma membrane; cytosol; chromosomes; ribosomes

Front 38

all prokaryotic cells have...

Back 38

no nucleus; DNA in a unbound region called nucleoid; no membrane bound organelles, cytoplasm bound by plasma membrane; domains Bacteria and Archaea

Front 39

all eukaryotic cells have...

Back 39

DNA in a nucleus that is bounded a membrane called nuclear envelope; membrane bound organelles; cytoplasm in teh region b/w the plasma membrane and nucleus; domains Protists, Fungi, Animal and Plant; usually much larger than prok

Front 40

plasma membrane

Back 40

a selective barrier that allows sufficient passage of oxygen, nutrients and waste to service the volume of every cell; made of double layer of phospholipids

Front 41

What is the GOLGI APPARATUS?

Back 41

We can think of it as the center of manfacturing, warehousing, sorting and shipping.
- Products of the ER are modified and stored and then sent to other destinations.
- Specialized for secretion.

Front 42

The phospholipid tails and interior portions of membrane proteins are...; the phospholipid heads, exterior proteins/parts, and carbohydrate side chains are...; carb chains are only found on...

Back 42

Hydrophobic; hydrophilic and in contact with regions on either side of membrane; outer surface of plasma membrane

Front 43

Back 43

lack a true nucleus, no membrane bound organelles, simpler in structure and smaller; bacteria and archaea

Front 44

Describe the path of a product from the ER to the Golgi appartus.

Back 44

Product protein:
- arrives on the CIS face (recieving end)
- usual modified as it travels to the TRANS end (shipping side)
- proteins are usually transported to the plasma membrane for secretion.

Front 45

pili

Back 45

attachment structure son surface of some prok

Front 46

What is a LYSOSOME?

Back 46

A membranous sac of hydrolytic enzymes that an animal cell uses to digest all kinds of macromolecules. (Carry out intracellular digestion.) Food vacuole fuses with lysosome and enzymes digest food
- lysomal enzymes work best in the acidic environment found in lysosomes.

Front 47

nucleoid

Back 47

region where the cell's DNA is located (not enclosed by a membrane

Front 48

What is PHAGOCYTOSIS?

Back 48

The process of whereby amoebas and other protists eat by engulfing smaller organisms or other food particles; forms food vacuoles

Front 49

ribosomes

Back 49

organelles that synthesize proteins

Front 50

What is AUTOPHAGY?

Back 50

The process by which lysosomes use their hydrolytic enzymes to reyclce the cell's own organic material such as another damaged organelle

Front 51

cell wall

Back 51

help shape and protect cell, made of cellulose, other sugars and protein, only in plants

Front 52

What is a VACUOLE?

Back 52

Membrane sac that aids in digestion of cell and the release of cellular waste products. They carry out hydrolysis and similar to lysosomes
-examples - food, contractile, and central

Front 53

capsule

Back 53

jelly like outer coating of many prok

Front 54

What is a TONOPLAST?

Back 54

The membrane that encloses the large, central vacuole in a plant cell.

Front 55

flagella

Back 55

locomotion of organelles of some bacteria and animal cells

Front 56

How important is the VACUOLE to a plant cell?

Back 56

Extremely. Plant cells enlarge as their vacuoles absorb water, enabling the cell to become larger with a minimal investment in the new cytoplasm.

Front 57

centrosome

Back 57

region where the cell's microtubules are initiated; in an animal cell, contains a pair of centrioles

Front 58

What is a MITOCHONDRIA?

Back 58

- Sites of cellular respiration and metabolic process that generates ATP by extracting energy from sugar, fats and other fuels with oxygen. Power house of the cell

Front 59

cytoskeleton

Back 59

reinforces cells's shape functions in cell movement; components are made of protein; microfilaments, intermediate filaments and microtubules

Front 60

What are CHLOROPLASTS?

Back 60

Found only in plants and algae, are the sites of photosynthesis.
- contain the green pigment chlorophyll, along with enzymes and other molecules that function in the photosynthetic production of sugar.

Front 61

microvilli

Back 61

projections that increase the cell's surface area

Front 62

Are MITOCHONDRIA and CHLOROPLASTS part of the endomembrane system?

Back 62

No, these organelles have at least two membranes separating the innermost space from the cytosol.
- they contain DNA that programs the synthesis of the proteins made on the organelle's own ribosomes, have a double membrane and have proteins made from free ribosomes

Front 63

peroxisome

Back 63

organelles with specialized metabolic functions; produces hydrogen peroxide

Front 64

What is a PLASTID?

Back 64

a plant organelle; e.g. The Chloroplast is a specialized member, give green color. Amyloplasts are colorless plastids that store starch, chromoplasts give fruit the yellow and orange color

Front 65

What is the CYTOSKELETON?

Back 65

Network of fibers extending throughout the cytoplasm.
- Gives mechanical support to the cell and helps maintain its shape
- Plays a major role in organizing the structures ad activities of the cell through motility and regulation
- Composed of microtubules microfilaments and intermediate filaments.

Front 66

Is the CYTOSKELETON more important in plant or animal cells?

Back 66

Animal cells b/c they lack walls.

Front 67

What is CELL MOTILITY?

Back 67

Encompasses both changes in cell location and more limited movements of parts of the cell.
- Requires the interaction of the cytoskeleton with proteins called MOTOR PROTEINS

Front 68

What is the function of the MICROTUBULES?

Back 68

- Thickest component of the cytoskeleton
- They shape and support the cell
- Serve as tracks along which organelles equipped with motor proteins can move
- Responsible for the separation of chromosomes during cell division
- Act as compression-resisting girders of the cytoskeleton
- provide support to the motion of CILIA and FLAGELLA

Front 69

What is the CENTROSOME?

Back 69

A region often locatd near the nucleus that is considered to be a "microtubule-organizing center"

Front 70

What are CENTRIOLES?

Back 70

Found in the centrosome of the animal cell, composed of microtubules arranged in a ring
- Before a cell divides, centrioles replicate

Front 71

Do plant cells have CENTROSOMES/CENTRIOLES?

Back 71

- Both have centrosomes
- Plant cells do not have centrioles

Front 72

What is a DYNEIN?

Back 72

Dynein arms are responsible for he bending movements of cilia and flagella.
- Motor protein
- Performs a complex cycle of movements caused by changes in the conformation of the protein with ATP providing the energy for these changes. (Like a cat walking along along the branch of a tree.)

Front 73

Provide info on a MICROFILAMENT.

Back 73

- also called ACTIN filaments
- appear to be present in all eukaryotic cells
- role is to bear tension (pulling forces) between the microtubules
- form a 3-D network inside the plasma membrane that helps support the cells shape
- known for their role in cell molility

Front 74

What is a PSEUDOPODIA?

Back 74

Assist in the movement of amoeba

Front 75

What is MYOSIN?

Back 75

Motor protein that help with the movement of microfilaments

Front 76

What are INTERMEDIATE FILAMENTS?

Back 76

- Also specialized for bearing tension
- Larger than microfilament but smaller than microtubules
- more permanent fixtures in cells than microtubules or microfilaments
- they assist with the anchoring of the nucleus

Front 77

What is PLASMODESMATA?

Back 77

channels that perforate plant cell walls; thru this, water and small solutes can pass from cell to cell

Front 78

What is SELECTIVE PERMEABILITY?

Back 78

The plasma membrane allows some membranes to cross it more easily than others.

Front 79

What is a GLYCOLIPID?

Back 79

A carbohydrate that is covalently bonded to lipids (e.g. to phospholipids in the plasma membrane layer)

Front 80

What is CISTERNAL MATURATION MODEL?

Back 80

the cisternae of the Golgi actually progress forward from the cis (flat) to the trans(bubbled) face of the Golgi, carrying and modifying their protein cargo as they move

Front 81

What do CONTRACTILE VACUOLES do in protists?

Back 81

in protists, they pump excess water out of cell , thereby maintaing the appropriate concentration of salt and other molecules

Front 82

What are roles of CONTRACTILE VACUOLES in plants?

Back 82

holds reserves of important organic compounds; plant cell's main repository of inorganic ions, as a K and Cl; contain pigments that color cell; help protect the plant against predators by containing compounds that are poisonous; can become very large

Front 83

What is the function of MOTOR PROTEINS?

Back 83

bring movement of cilia and flagella by propelling them; causes muscle cells to contract; aid vesicles in budding off and moving along Golgi body track; aid materials that move about inside cytoplasm

Front 84

What is INTERSTIAL FLUID?

Back 84

liquid b/w cells

Front 85

What is TIGHT JUNCTIONS?

Back 85

membranes of neighboring cells pressed together, preventing leakage of extracellular fluid

Front 86

Name the INTERCELLULAR JUNCTIONS

Back 86

plasmodesmata, tight junctions, desosomes, gap junctions

Front 87

What is GAP JUNCTIONS?

Back 87

(communicating junctions) provide cytoplasmic channels b/w adjacent cells

Front 88

What are ANCHORING (adherence) JUNCTIONS?

Back 88

(desosomes) fasten cells together into strong sheets

Front 89

What is the EXTRACELLULAR MATRIX (EMC)?

Back 89

animal cells lack walls but have this instead; made up of glycoproteins; function in support, adhesion, movement and regulation

Front 90

Examples of GLYCOPROTEINS

Back 90

collagen, proteoglycans, and fibronectin

Front 91

What are INTEGRINS?

Back 91

ECM proteins bind to receptor proteins in the plasma membrane