1.2 and 1.3

Question 1

light microscope

Answer 1

observe living specimens, structure of the cells, max magnification 400x, size down to 0.2 micrometers as separate objects

Question 2

electron microscope

Answer 2

higher resolution, down to 1 nanometer; magnification by 500,000x; studying small cellular structures, observe non-living specimens in black and white, ultrastructure of the cells

Question 3

reproduction of prokaryotes

Answer 3

binary fission - asexual

Question 4

prokaryotes

Answer 4

bacteria and archaea

Question 5

parts of prokaryotes

Answer 5

nucleoid, plasmid, naked DNA, plasma membrane, cell wall, cytoplasm, 70S ribosomes, pili, flagellum

Question 6

role of pili

Answer 6

protein filaments on the cell wall that help in cell adhension and in transfering of DNA between 2 cells

Question 7

role of flagella

Answer 7

much longer the pili, responsible for locomotion of the organism, whip-like movement propels the cell along
70S ribosomes - sites of protein synthesis

Question 8

***role of plasmids

Answer 8

small circles of DNA that carry a few genes, give the cell antibiotic resistance and are used in creating genetically modified bacteria

Question 9

draw a prokaryote

Answer 9

…

Question 10

draw an eukaryote

Answer 10

…

Question 11

***eukaryota

Answer 11

protocista, fungi, plantae, animalia

Question 12

***advantages of compartmentalization of cells

Answer 12

1. greater efficiency of metabolism
2. internal conditions like pH can be differentiated in cell to maintain the optional conditions for different enzymes
3. isolations of toxic or damaging substances away from the cytoplasm
4. flexibility of changing the numbers and position of organelles within the cell based on the cell’s requirements

Question 13

***role of nucleus

Answer 13

contains chromosomes, consisting of DNA associated with with histone proteins

Question 14

***chromatin

Answer 14

uncoiled chromosomes

Question 15

***role of nucleolus

Answer 15

part of nucleus responsible for production of ribosomes

Question 16

role of 80S ribosomes

Answer 16

synthesize proteins, releasing them to work in the cytoplasm, constructed in nucleolus

Question 17

role of sER

Answer 17

produces storing lipids, including steoids

Question 18

role of rER

Answer 18

transports protein produced by ribosomes on its surface to the GA

Question 19

role of GA

Answer 19

processes and packages proteins, which are ultimately released in Golgi vesicles

Question 20

role of vesicles

Answer 20

very small vacuoles used to transport materials inside the cells, produced by the cell, and release substances by fusing with the cell membrane

Question 21

role of lysosomes

Answer 21

absent from plant cells; formed in Golgi vesicles, contain high concentration of proteins, contain digestive enzymes used to break down ingested food in vesicles or break down organelles in the cell or the whole cell, destruction of microbes and of old cellular organelles

Question 22

role of centrioles

Answer 22

absent from plant cells; process of nuclear division by helping establish the mictrotubules

Question 23

***role of vacuole

Answer 23

helps in the osmotic balance of the cell and of old cellular organelles

Question 24

role of chloroplast

Answer 24

absent from animal cells; contain pigments like chlorophyll, responsible for photosynthesis

Question 25

microtubules

Answer 25

cylindrical tubes in the cytoplasm that move that move chromosomes during cell division

Question 26

***cilia and flagella

Answer 26

ring of 0 double microtubules + 2 central ones

Question 27

hydrophilic

Answer 27

polar, attracted to water

Question 28

hydrophobic

Answer 28

not attracted to water

Question 29

amphipathic

Answer 29

both hydrophilic and hydrophobic

Question 30

Davson-Danielli model of membrane structure

Answer 30

phospholipid bilayer is sandwiched between 2 protein layers on either side of the membrane

Question 31

***shortcomings of Davson-Danielli

Answer 31

1. it is assumed that all membranes had identical structures (how can different types of membranes carry out different functions?) 2. proteins are amphipathic, but largely non-polar

Question 32

Singer and Nicolson model of membrane structure

Answer 32

proteins are individually embedded in the phospholipid bilayer, fluid mosaic model, proteins move around

Question 33

***functions of membrane proteins

Answer 33

1. hormone binding sites 2. immobilized enzymes 3. cell adhension 4. cell-to-cell communication 5. channels 6. pumps

Question 34

2 groups of proteins

Answer 34

integral and peripheral proteins

Question 35

integral proteins

Answer 35

hydrophobic, embedded in hydrocarbon chains in the center of the membrane, with hydrophilic parts projecting through the regions for phosphate heads on either side

Question 36

***polytopic integral proteins

Answer 36

go all the way

Question 37

***monotopic

Answer 37

penetrating just one surface

Question 38

***glycoproteins

Answer 38

proteins with oligosaccaride - hormone receptors

Question 39

peripheral proteins

Answer 39

hydrophilic on the surface; not embedded in the membrane, attached to the surface of integral proteins, some have 1 hydrocarbon chain attached to them, can be monotopic or attach to the surface

Question 40

***cholesterol

Answer 40

a steroid, only found in animal cell membranes, helps maintain the structure of the cell membrane; amphipathic; sex hormones are synthesized from it; type of lipid (nor fat or oil); reduces membrane permeability to hydrophilic molecules - Na and H

Question 41

***cholesterol at low temperature

Answer 41

disrupts the regular packing of the hydrocarbon tails of phospholipid molecules, which prevents the solidification of the membrane

Question 42

tails behave as ?

Answer 42

liquid

Question 43

heads behave as ?

Answer 43

solids

Question 44

***fluidity of membranes and cholesterol

Answer 44

membranes need to be fluid enough so that cells can move and that required substances can move across the membrane, but if too fluid, membrane couldn't effectively restrict the movement of substances across itself