Deck 3: The Cell

Question 1

Which of the following individuals argued in favor of the theory of spontaneous generation?

A) Francesco Redi
B) Louis Pasteur
C) John Needham
D) Lazzaro Spallanzani

Answer 1

The theory of spontaneous generation was first proposed by the Greek philosopher Aristotle (384-322 BC). According to this theory, life arises from the non-living matter, if that material contains "pneuma" (means, vital heat). This theory was persisted till 17 th century. Several of the scientists supported and opposed this theory.
Francesco Redi (1626-1697) was an Italian physician, who first refused the theory of spontaneous generation. He refused the idea of spontaneous generation of maggots (larva of flies) from the meat.
Louis Pasteur was a French chemist during the 19 th century. He disproved the theory of spontaneous generation and won the debate on this topic and Academy's prize. He filtered the air through a gun-cotton filter and observed the presence of microbes on the filter under the microscope.
Lazzaro Spallanzani (1729-1799) refused the idea of spontaneous generation. He proposed that the life arises from air.
Thus, the options (a), (b), and (d) are incorrect.
John Needham (1713-1781) supported the theory of spontaneous generation. He took a broth infused with animal and animal mallet and boiled it for a brief period (to kill the pre-existing microbes). He sealed the flasks for few days and later observed the microbial growth in the container. However, the pre-heating did not actually kill the pre-existing microbes.
Hence, the correct answer is
.

Question 2

Which of the following individuals is credited for definitively refuting the theory of spontaneous generation using broth in swan-neck flask?

A) Aristotle
B) Jan Baptista van Helmont
C) John Needham
D) Louis Pasteur

Answer 2

The theory of spontaneous generation was first proposed by the Greek philosopher Aristotle (384-322 BC). According to this theory, life arises from the non-living matter, if that material contains "pneuma" (means, vital heat). This theory was persisted till 17 th century. Several of the scientists supported and opposed this theory.
Thus, the option (a) is incorrect.
Jan Baptista van Helmont was a Flemish scientist (17 th century). He supported the theory of spontaneous generation and proposed that the mice can arise spontaneously arise from wheat kernels and rags open to air.
Thus, the option (b) is incorrect.
John Needham (1713-1781) supported the theory of spontaneous generation. He took a broth infused with animal and animal mallet and boiled it for a brief period (to kill the pre-existing microbes). He sealed the flasks for few days and later observed the microbial growth in the container. However, the pre-heating did not actually kill the pre-existing microbes.
Thus, the option (c) is incorrect.
Louis Pasteur was a French chemist during the 19 th century. He disproved the theory of spontaneous generation and won the debate on this topic and Academy's prize. He filtered the air through a gun-cotton filter and observed the presence of microbes on the filter under the microscope.
Pasteur performed an experiment using the swan-neck flasks (long and twisted necks). These flasks can exchange the air inside with the external air, but the microbes from the external air cannot enter into the flask, instead they trapped in the flask of the neck. He sterilized the broth in one of the flasks. With this experiment, he observed that the growth did not occur in the sterile broth.
After that he broke the necks of the flasks and allowed contamination of the broth, microbial growth was observed.
Hence, the correct answer is
.

Question 3

Which of the following experimented with raw meat, maggots, and flies in an attempt to disprove the theory of spontaneous generation.

A) Aristotle
B) Lazzaro Spallanzani
C) Antonie van Leeuwenhoek
D) Francesco Redi

Answer 3

The theory of spontaneous generation was first proposed by the Greek philosopher Aristotle (384-322 BC). According to this theory, life arises from the non-living matter, if that material contains "pneuma" (means, vital heat). This theory was persisted till 17 th century. Several of the scientists supported and opposed this theory.
Thus, the option (a) is incorrect.
John Needham (1713-1781) supported the theory of spontaneous generation. He took a broth infused with animal and animal mallet and boiled it for a brief period (to kill the pre-existing microbes). He sealed the flasks for few days and later observed the microbial growth in the container. However, the pre-heating did not actually kill the pre-existing microbes.
Lazzaro Spallanzani (1729-1799) refused the idea of John Needham. He proposed that the life arises from air.
Leeuwenhoek, famously known as Antony Leeuwenhoek is a popular scientist known for his works with the improvement of microscope. He is known as "father of microbiology."
Thus, the options (b) and (c) are incorrect.
Francesco Redi (1626-1697) was an Italian physician, who first refused the theory of spontaneous generation. He refused the idea of spontaneous generation of maggots (larva of flies) from the meat.
He performed an experiment in which he allowed one pair of jars with the meat to open air and another pair of jars with the meat covered with a gauge. The third set of jars with meat is sealed with the cork. He observed the growth of maggots in the jar left open to air and covered with gauge. But the jar sealed with the cork did not show any growth of maggots. Thus, he proved that maggots do not arise spontaneously from meat.
Hence, the correct answer is
.

Question 4

Which of the following individuals did not contribute to the establishment of cell theory?

A) Girolamo Fracastoro
B) Matthias Schleiden
C) Robert Remak
D) Robert Hooke

Question 5

Whose proposal of the endosymbiotic theory of mitochondrial and chloroplast origin was ultimately accepted by the greater scientific community?

A) Rudolf Virchow
B) Ignaz Semmelweis
C) Lynn Margulis
D) Theodor Schwann

Question 6

Which of the following developed a set of postulates for determining whether a particular disease is caused by a particular pathogen?

A) John Snow
B) Robert Koch
C) Joseph Lister
D) Louis Pasteur

Question 7

Which of the following terms refers to a prokaryoticcell that is comma shaped?

A) coccus
B) coccobacilli
C) vibrio
D) spirillum

Question 8

Which bacterial structures are important for adherence to surfaces? (Select all that apply.)

A) endospores
B) cell walls
C) fimbriae
D) capsules
E) flagella

Question 9

Which of the following cell wall components is unique to gram-negative cells?

A) lipopolysaccharide
B) teichoic acid
C) mycolic acid
D) peptidoglycan

Question 10

Which of the following terms refers to a bacterial cell having a single tuft of flagella at one end?

A) monotrichous
B) amphitrichous
C) peritrichous
D) lophotrichous

Question 11

Bacterial cell walls are primarily composed of which of the following?

A) phospholipid
B) protein
C) carbohydrate
D) peptidoglycan

Question 12

Which of the following organelles is not part of the endomembrane system?

A) endoplasmic reticulum
B) Golgi apparatus
C) lysosome
D) peroxisome

Question 13

Which type of cytoskeletal fiber is important in the formation of the nuclear lamina?

A) microfilaments
B) intermediate filaments
C) microtubules
D) fibronectin

Question 14

Sugar groups may be added to proteins in which of the following?

A) smooth endoplasmic reticulum
B) rough endoplasmic reticulum
C) Golgi apparatus
D) lysosome

Question 15

Which of the following structures of a eukaryotic cell is not likely derived from endosymbiotic bacterium?

A) mitochondrial DNA
B) mitochondrial ribosomes
C) inner membrane
D) outer membrane

Question 16

Which type of nutrient uptake involves the engulfment of small dissolved molecules into vesicles?

A) active transport
B) pinocytosis
C) receptor-mediated endocytosis
D) facilitated diffusion

Question 17

Which of the following is not composed of microtubules?

A) desmosomes
B) centrioles
C) eukaryotic flagella
D) eukaryotic cilia

Question 18

Exposure to air is necessary for microbial growth.

Question 19

Bacteria have 80S ribosomes each composed of a 60S large subunit and a 40S small subunit.

Question 20

Mitochondria in eukaryotic cells contain ribosomes that are structurally similar to those found in prokaryotic cells.

Question 21

The assertion that "life only comes from life" was stated by Louis Pasteur in regard to his experiments that definitively refuted the theory of ___________.

Question 22

John Snow is known as the Father of _____________.

Question 23

The ____________ theory states that disease may originate from proximity to decomposing matter and is not due to person-to-person contact.

Question 24

The scientist who first described cells was _____________.

Question 25

Prokaryotic cells that are rod-shaped are called _____________.

Question 26

The type of inclusion containing polymerized inorganic phosphate is called _____________.

Question 27

Peroxisomes typically produce _____________, a harsh chemical that helps break down molecules.

Question 28

Microfilaments are composed of _____________ monomers.

Question 29

Explain in your own words Pasteur's swan-neck flask experiment.

Question 30

Explain why the experiments of Needham and Spallanzani yielded in different results even though they used similar methodologies.

Question 31

How did the explanation of Virchow and Remak for the origin of cells differ from that of Schleiden and Schwann?

Question 32

What evidence exists that supports the endosymbiotic theory?

Question 33

What were the differences in mortality rates due to puerperal fever that Ignaz Semmelweis observed? How did he propose to reduce the occurrence of puerperal fever? Did it work?

Question 34

What is the direction of water flow for a bacterial cell living in a hypotonic environment? How do cell walls help bacteria living in such environments?

Question 35

How do bacterial flagella respond to a chemical gradient of an attractant to move toward a higher concentration of the chemical?

Question 36

What existing evidence supports the theory that mitochondria are of prokaryotic origin?

Question 37

Why do eukaryotic cells require an endomembrane system?

Question 38

Name at least two ways that prokaryotic flagella are different from eukaryotic flagella.

Question 39

What would the results of Pasteur's swan-neck flask experiment have looked like if they supported the theory of spontaneous generation?

Question 40

Why are mitochondria and chloroplasts unable to multiply outside of a host cell?

Question 41

Why was the work of Snow so important in supporting the germ theory?

Question 42

Label the parts of the prokaryotic cell.

Label the parts of the prokaryotic cell.

Question 43

Which of the following slides is a good example of staphylococci?

Question 44

Provide some examples of bacterial structures that might be used as antibiotic targets and explain why.

Question 45

The causative agent of botulism, a deadly form of food poisoning, is an endospore-forming bacterium called Clostridium botulinim. Why might it be difficult to kill this bacterium in contaminated food?

Question 46

Label the following parts of this eukaryotic cell.

Question 47

How are peroxisomes more like mitochondria than like the membrane-bound organelles of the endomembrane system? How do they differ from mitochondria?

Question 48

Why must the functions of both lysosomes and peroxisomes be compartmentalized?