Bio Test #5 Flashcards Preview

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Flashcards in Bio Test #5 Deck (75):
1

What is the monomer for nucleic acids?

nucleotide

2

What is the polymer for nucleic acids?

DNA & RNA

3

What are the 3 main parts of the structure of Nucleotide?

a sugar
a phosphate group
a nitrogenous base

4

Why are there different types of nucleotides?

Different type of nucleotides because different nitrogenous bases attached to them

5

What are the four different bases?

Adenine
Guanine
Cytosine
Thymine

6

What group are the bases in?

Adenine & Guanine are Purines
Cytosine & Thymine are Pyrimidines

7

How are nucleotides linked together to create 1 strand?

Nucleotides are linked together by a covalent bond between the carbon in the 3rd position & the phosphate group

8

How many strands is DNA made of?

2

9

What keeps DNA strands together?

The strands are held together by hydrogen bonds between bases

10

What does complementary base pairing consist of?

Adenine only bonds with Thymine
Cytosine only bonds with Guanine

11

How many hydrogen bonds are needed for each complementary base pair?

Between Adenine & Thymine there are 2 hydrogen bonds
Between Cytosine & Guanine there are 3 hydrogen bonds

12

What are the functions of DNA?

DNA makes up our genes, it contains instructions to synthesize proteins for the whole, it transfers hereditary info from cell to cell

13

What are the functions of RNA?

makes mRNA (messenger), tRNA (transfer), rRNA (ribosomal)
copies & transports DNA instructions out of the nucleus (mRNA)
translates instructions into proteins (mRNA, tRNA, rRNA)
can also function as an enzyme

14

cytology

science that studies cells' structure and functions

15

cytologist

person that studies cells

16

Cell Theory

1. All organisms are made of cells & cells' products
2. Cells are the smallest & simplest, structural & function unit of life
3. Cells come from pre-existing

17

Cell Shapes

squamous, cuboidal, columnar, speroid, discoid, fusiform, fibrous

18

squamous

flat & angular; cover the esophagus, skin, lining of cavities, capillaries, alveoli

19

cuboidal

cube, liver cells

20

columnar

taller than wide, lining of intestine

21

speroid

roundish, fat cell

22

discoid

disk shape, red blood cell

23

fusiform

thick in the middle & tapered at end, smooth muscles

24

fibrous

thread like, skeletal muscle

25

virus

a non-cellular structure composed of DNA/RNA and surrounded by a protein coat

26

What are characteristics of viruses?

Not cells made of the same material; have same genetic material
have the ability to evolve through natural selection
require a host to reproduce and survive
have an incubation period that varies according to virus

27

How important is incubation?

It is crucial to the virus spreading

28

What process does virus reproduction use?

Lytic Process

29

How do viruses reproduce?

1. Adsorption
2. Entry
3. Replication
4. Assembly
5. Release

30

adsorption

virus attaches to the host cell

31

entry

virus injects its DNA/RNA into the cell

32

replication

genetic material of the virus takes control of the host cell and tells the cell to make viral DNA/RNA and protein coats

33

assembly

viral DNA directs host cell to assemble viruses

34

Release

new viruses destroy the membrane of the host cell and are released outside

35

What are prokaryotic cells?

Do not have nucleus, considered to be the most similar to a primordial cell

36

What do scientists believe about the first cell?

They believe that it was developed from non-living chemical substances. Even though this does not happen now and cells only originate from other cells

37

What are prokaryotes also called?

Prokaryotes are also called Bacteria

38

What are characteristics of prokaryotes?

They have few internal structures, but have a great variety of shapes & metabolic activity

39

What are 3 examples of Prokaryotes?

Blue-Green Bacteria
Nitrogenfixing Bacteria
Decomposers

40

Blue-green Bacteria

photosynthetic; make their own food using energy from sun; autotroph (self-feeding)

41

Nitrogenfixing Bacteria

absorb N2 from atmosphere and transform it into nitrate (NO3) & nitrite (NO2) which are then used by plants

42

Decomposers

use decaying matter & through fermentation break it back into simpler nutrients, important in our digestive system

43

What are the 3 main shapes of Prokaryotes?

round/cocci
rod/bacillus
spiral

44

What is Gramstain and its significance?

a series of stains poured over a bacteria and
it indicates presence of certain chemicals in cell wall (purple if contains stain, pink if not)

45

How can bacteria be classified?

Through its shape, gramstain, and antibiotic resistance

46

How do you test bacteria's antibiotic resistance?

the bacteria is grown on plates with different kinds of antibiotics and if they grow that means they are resistant to that antibiotic

47

What are the functions for cell wall?

maintain shape, protect from others, and prevents cell from bursting

48

What are the functions for cell membrane?

separates inside of cell from outside environment, allows things in & out of the cell & regulates flow

49

What are the functions for mesosome?

involved in ATP production

50

What are the function for cytoplasm?

to contain enzymes for chemical reactions

51

What is the structure of cell wall?

Cell wall maintains modified sugar polymers called peptydeglygans

52

What is the structure of cell membrane?

made of phospholipids

53

What is the structure of mesosome?

made by foldings of the cell membrane

54

What is the structure of cytoplasm?

structure is a semi-transparent gelatinous

55

What are the functions for ribosomes?

synthesize protein by translating mRNA

56

What are the functions of Naked DNA?

store genetic info, transfer genetic info to daughter cells, directs all activities of the cell

57

What is the structure of ribosomes?

made of rRNA organized into 2 sub units; prokaryote cells have small ribosomes called "70s"

58

What is the structure of Naked DNA?

made of nucleotides and is organized in a loop

59

Describe other structures

their presence varies:
Pilus, Flagellum, Capsule, Endospore

60

Describe Pilus/i

an "other structure" there are 2 types
1. sexpilus
2. common pilus

61

sexipilus

stabilize bacteria during conjugation

62

common pilus

attachment to surfaces, defense from phagocytic cells

63

Describe Flagellum

long slender projection; its function is locomotion; can be either polar or peritrichus

64

locomotion

moves in a whip like motion and propels cell forward

65

Polar Flagellum

can have more than one strand on one side

66

Peritrichus Flagellum

can have more than one strand on multiple sides

67

Describe Capsule

hard covering; it protects

68

Describe Endospore

hard covering; function: survival in periods of environmental stress (changes in temp., pH, chemicals)

69

What are the 2 main processes of reproduction of bacteria?

Binary Fission & Bacterial Conjugation

70

Binary Fission

asexual reproduction; not the same as mitosis

71

What are the advantages & disadvantages of Binary Fission?

Adv: it allows bacteria to grow rapidly
Dis: because all bacteria are identical, if something kills/harms one bacteria, it will affect the whole population
This process allows bacteria to grow exponentially

72

Bacterial Conjugation

2 genetic material exchange between 2 already existing bacteria

73

Plasmid

extra chromosomal DNA, capable or replicating independently from the main DNA; can carry specific properties

74

What are considerations of Bacterial Conjugation?

This is how bacteria can acquire new properties that allow them to survive & evolve

75

How do you prevent the ability for bacteria to survive & evolve too often?

enforce prudent use of antibiotic
improve sanitation to avoid spread of bacteria
invest in research
take antibiotic for whole course of treatment