Endosymbiosis -Exam 3

Question 1

far more complex than prokaryotic cells

Answer 1

Eukaryotic cells

Question 2

a nucleus housing highly structured chromosomes

Answer 2

Eukaryotic cells

Question 3

abundant intracellular membranes, including the rough and smooth ER and the Golgi apparatus

Answer 3

Eukaryotic cells

Question 4

mitochondria

in plants, chloroplasts

Answer 4

Eukaryotic cells

Question 5

divide by mitosis

Answer 5

Eukaryotic cells

Question 6

Created 3.45 billion years ago

Answer 6

Fossils of prokaryotes

Question 7

arose between 1.5 and 2 billion years ago

Answer 7

Eukaryotic cells

Question 8

define endosymbiotic theory

Answer 8

how eukaryotes could have evolved from pro-karyotes; a larger cell engulfed smaller cells that evolved into the mitochondrion and the chloroplast

Question 9

“living together inside”; different cells live to-gether, one cell inside another; common among modern-day microbial eukaryotes)

Answer 9

Endosymbiosis

Question 10

common endosymbionts in marine animals and protozoans

Answer 10

dinoflagellates, photosyn-thetic protists

Question 11

endosymbiotic theory was proposed by

Answer 11

Lynn Margulis in 1967

Question 12

5 similarities between mitochondria and bacteria

Answer 12

are 1 to 4 mm in length
are surrounded by two membranes
use O2 to generate ATP
have their own DNA
grow and divide by binary fission

Question 13

3 additional similarities between mitochondria and bacteria

Answer 13

Their genes are similar (and different from the genes in the nucleus

Their ribosomes are similar (and different from the ribosomes in the cytoplasm)

Their enzymes (including DNA and RNA polymerases) are similar (and different from the enzymes in the nucleus and cytoplasm

Question 14

arose as the environment was changing from anaerobic (O2 absent) to aerobic (O2 present)

Answer 14

Eukaryotic cells

Question 15

The increase in atmospheric O2 was due to

Answer 15

photosynthesis by cyanobacteria

Question 16

toxic to anaerobic or-ganisms, so the “Great Oxygenation Event” about 2.3 billion years ago resulted in mass extinction

Answer 16

Molecular oxygen

Question 17

1. evolution of eukaryotic cells

Answer 17

The origin of a flexible cell surface; (The origin of a cytoskeleton)

Question 18

2. evolution of eukaryotic cells

Answer 18

The origin of a nuclear envelope

Question 19

3. evolution of eukaryotic cells

Answer 19

The origin of phagocytosis and the appearance of digestive vesicles or vacuoles

Question 20

4. evolution of eukaryotic cells

Answer 20

The endosymbiotic acquisition of the mitochondria and chloroplasts

Question 21

The prokaryotic cell wall was lost, allow-ing the cell to grow larger
As cell size increases, the surface area-to-volume ratio decreases

Answer 21

flexible cell surface

Question 22

• infolding can occur, creating internal membranes and making more surface area
• allowed endo-cytosis to develop

Answer 22

flexible cell surface

Question 23

likely to have arisen from the plasma membrane

Answer 23

nuclear envelope

Question 24

______ of a prokaryote is attached to the plasma membrane

Answer 24

DNA

Question 25

created a double layer of phospholipids that surrounded the DNA, giving rise to the nucleus

Answer 25

Inward folding of the plasma membrane proposed by de Duve in 1966)

Question 26

infolding of the plasma membrane was also the most plausible origin of other or-ganelles,

Answer 26

the rough endoplasmic reticulum the smooth endoplasmic reticulum the Golgi apparatus

Question 27

had a cytoskeleton and perhaps flagella

Answer 27

the first true eukaryotes

Question 28

allowed a conversion from extracellular digestion to intracellular digestion

Answer 28

Membrane internalization

Question 29

the process in which food particles are engulfed and digested

Answer 29

phagocytosis

Question 30

Digestive vesicles and vacuoles were created by the process of

Answer 30

phagocytosis

Question 31

phagocytized a proteobacterium

Answer 31

primitive eukaryotic

Question 32

Rather than digesting it.............

Answer 32

the eukaryotic cell maintained the proteobacterium inside its cytoplasm

Question 33

evolved into the mitochondrion

Answer 33

proteobacterium

Question 34

Mitochondria are believed to have originated from the

Answer 34

a-proteobacteria, specifically the species Rickettsia

Question 35

species are intracellular parasites in many plants and animals, including ticks, fleas and lice

Answer 35

Rickettsia

Question 36

Disease caused from Rickettsia

Answer 36

Typhus and rocky mountain spotted fever

Question 37

include a high fever, severe muscle pain and a rash, which usually starts on the wrists and ankles

Answer 37

Rocky Mountain spotted fever

Question 38

free within the cytoplasm of the host cell

Answer 38

Rickettsia cell

Question 39

fed on carbon compounds and released H+

Answer 39

proteobacterium

Question 40

_______ cell evolved the ability to feed it carbon compounds and use the H+ to make ATP

Answer 40

primitive eukaryotic

Question 41

initial function of the ____ may have been to detoxify the increasing amounts of O2 in the atmosphere by reducing it to water

Answer 41

mitochondrion

Question 42

By making a “food-for-hydrogen” swap, ______ gained an enormous advantage over other cells

Answer 42

the eukaryotic cell

Question 43

carry out cellular respiration

Answer 43

mitochondria

Question 44

yields far more energy from the breakdown of carbon compounds than an-aerobic pathways do

Answer 44

Respiration

Question 45

eukaryotic cells can be considerably larger with..

Answer 45

hundreds of mitochondria

Question 46

gave rise to multi-cellular fungi, animals and plants

Answer 46

Single-celled eukaryotes

Question 47

a primitive eukaryotic cell incorporated a photosynthetic prokaryote related to

Answer 47

modern-day cyanobacteria --> cyanobacteria then evolved into chloroplasts

Question 48

Cells with chloroplasts gave rise to modern

Answer 48

plants

Question 49

Cells containing chloroplasts were able to carry out ___

Answer 49

photosynthesis

Question 50

the ability to harness the energy of sunlight to make carbon compounds

Answer 50

advantage over non-photosynthetic cells; origin of eukaryotic auto-trophs

Question 51

as the bacteria were engulfed, they were surrounded by ____ causing double membrane around mitochondrion and the chloroplast

Answer 51

eukaryotic cell’s plasma membrane

Question 52

the large majority of the genes in the mitochondrion and chloroplast were transferred to

Answer 52

the nucleus

Question 53

Most of their proteins are thus made in the ____ and then imported into the ___

Answer 53

cytoplasm | organelle

Question 54

The mitochondrion and chloroplast are thus ______ of living independently

Answer 54

incapable