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Flashcards in Chapter 1 Deck (68):
1

What are the three primary cells that feed of energy?

Organotrophic
phototrophic
lithotrophic

2

What is Organotrophic?

cells that feed on other organic molecules

3

What is phototrohic?

cells that feed on sunlight

4

What is lithotrophic?

Cells that feed on minerals from the earth

5

What type of cells are the most abundant form?

phototrophic
lithotrophic

Organotrophic cells could not survive without either

6

What are aerobic lithothrophes?

Cells that use minerals for energy and atmospheric oxygen to drive the reactions

7

What are anaerobic lithotrophs?

Cells that use minerals for energy but do not use atmospheric oxygen to drive the reactions

8

What are the two basic classifications of cells?

Eukaryotes- membrane enclosed DNA
Prokaryotes- Non enclosed DNA

9

Name some characteristics of prokaryotes?

live as individuals
spherical, rod shaped
cell wall
single cytoplasmic compartment
no organized internal structure
measure only a few microns

10

What are the main domains of life?

Bacteria (eubacteria)
Archaea (archaeabacteria)
Eukaryotes

11

Which domains are prokaryotes?

Bacteria (eubacteria)
Archaea (archaeabacteria)

12

What cause different species to arise?

Mutation
Natural selection

13

How is the relation between different closely related species traced?

Some parts of the genome is mutates a lot. some parts of the genome is highly conserved.

14

How is all the life on earth related?

Through the ribosomal small subunit RNA is virtually the same in all living organisms

15

Why are prokaryotes small?

Small surface area to volume.
maximizes the cells uptake of nutrients across the plasma membrane increasing the cell reproductive rate

16

How many genes does a prokaryote have?

1000-6000

17

What is the genome size of prokaryotes?

10^6 - 10^7

18

What are the ways a new gene is created?

Intragenic mutation
Gene duplication
Segment shuffling
Horizontal (intracellular) Transfer

19

What is intragenic mutation?

Changes in DNA sequence by DNA replication

20

What is gene duplication?

a gene is duplicated within same cell
free to evolve on different paths

21

what is Segment shuffling?

Two or more gene segments join to form a new gene

22

What is Horizontal (intracellular) transfer?

Transfer of DNA from one genome to another even from different species

23

How does homologs arise?

When part of the genome is mistankely duplicated.
both genes are related but may or may not serve seperate functions.

gives rise:
paralogs
othologs

24

What are homologs that derive from the same ancestral gene that are in two separate species and is similar in function?

Ortholog

25

What are homologs that derive from the same ancestral gene and are in the same species and diverged in function?

paralog

26

What type of cells readily has horizontal gene transfer?

prokaryotes- can result in cell picking up new traits

eukaryotes rarely have horizontal gene transfer

27

What cells are eukaryotes more similar in metabolic processes?

Bacteria
because of sexual mixing of early cells

28

What cells are eukaryotes more similar in infortion processing (DNA replication, transcription, translation).

archaea
because of sexual mixing of early cells

29

What is way to horizontal gene transfer?

Sexual reproduction
only occurs between the same species

30

What is one characteristic of horizontal gene transfer?

they leave an individual more closely related relatives with respect some genes.

31

What can be deduced from the a gene sequence?

The function of a gene

32

How many gene families are conserved over all three domain?

264

33

What is the model organism studied by molecular biologist?

E.coli

34

What are characteristics of E.coli that makes it ideal for study?

small
genetically differ from one to another
high rate of mutation
fast reproduction
has fundamental mechanisms of life

35

Where do eukaryotic cells keep their DNA?

The nucleus

36

What is the nuclear envelope?

double layer membrane that separates the nucleus from the cytoplasm

37

What are some features of a eukaryote?

membrane enclosed organelles
10x bigger than prokaryotes
1000x larger volume
cytoskeleton
lack cell wall
perform phagocytosis

38

What is one theory of the evolution of eukaryotic cells?

it was a predator cell,
requires large cell with flexible membrane and DNA to be in membrane away from the cytoskeleton

39

With what did primitive eukaryotic cells form a symbiotic relationship with?

Mitochondria wanted shelter for progeny
Eukaryotes wanted oxygen

40

What is mitochondria thought to be?

primitive oxygen metabolizing bacteria

41

What are some character of mitochondria?

Double plasma membrane
circular DNA
harness sugar to produce ATP
produce oxygen
has its own ribosomes
has own tRNA

42

What are chloroplast?

similar to mitochondria they perform photosynthesis
mostly in plants

43

What does plant cells have that protects them?

Cell wall- prevents them from changing shapes
no phagocytoses and no movement

44

What do fungi posses?

Cell wall and mitochodria
since cant change shape because of the cell wall and have no chloroplast they are scavengers

45

Why are the genomes of eukaryotes hybrid?

DNA sequences move from the symbionts (Mitochondria, Chloroplasts) to the host cell.

Symbionts genome is a cutdown version of bacterial genome.

46

Why are eukaryotes genome so large?

1) larger predatory cells
2) transposable elements

Majority DNA is non-coding

47

What is the role that noncoding DNA play in the cell?

They are regulatory genes that regulate the expression of adjacent genes
this is needed for formation of more complicated organisms.

48

How does the cells differentiate in the body?

They are contain the same genes. regulatory genes control the differentiation of cells and their activity.

49

How do regulatory proteins control genome activity?

They bind directly or indirectly to regulatory DNA or interfere with the ability of other proteins to do so .

Most of coding genome codes for regulatory proteins

50

What are some unicellular eukaryotes?

protozoa (protists)
unicellular algae
unicellular fungi

51

What are characteristics Saccharomyces cerevisiae (single celled yeast) that makes it an ideal eukaryotoic cell to study?

Small single celled
closely related to plants and animals
easy to grow in nutrient medium
cell wall
immobile
mitochondria
divides rapidly
reproduce by cell division or sexually (by changing growth conditions)

52

what plant is the model plat for study?

Arabidopsis

53

What are the animals whose genome is sequenced?

Caenorhabditis elegans
Drosphila melanogaster
Mus musculus
Homo sapiens

54

What are the organisms that is not considered living?

Viruses
prions
viroids

55

Why are viruses not considered living?

no metabolism
cannot reproduce outside of host cell

56

What are viroids?

virus like entities that infect plant s
they are smaller than viruses and do not have a protein coat

57

What are the types of bacterial cell walls?

Gram positive
gram negative
gram non-reactive

58

What are the parts common to both gram negative/positive cell walls?

flagellum
pilus
capsule
peptidoglycan (thicker in gram positive)
cytoplasmic membrane

59

What is in gram positive cell walls that is not in gram negative walls?

teichoic acid

60

what is common to gram negative that is not common to gram positive cell walls?

Endotoxin/LPS (outer membrane)

61

What are the common shapes of bacteria?

Cocci (spherical)
rod shaped (bacilli)
spiral shaped

62

What is the ribosomal large subunit of eukaryotes?

80s

63

What is the ribosomal subunit of prokaryotes?

70s

64

What are the cell wall made up of in eukaryotes?

cellulose or chitin

65

What type of E. Coli is used for labs?

E. Coli K12

66

what strain of E.Coli is pathogenic?

E.Coli 0157:H7 (EHEC)

67

What is the difference between K12 and )157:H7

0157 has 1.4 more DNA (5.5 MB versus 4.1)
1300-1600 more proteins than k12
131 is thought to be virulent
prophages may play an extra role in DNA

68

what are the types of horizontal gene transfer?

transduction
transformation
conjugation

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