Chapter 3 Part 4 Flashcards
(26 cards)
True or False: Exposure to air is necessary for microbial growth.
True
What type of ribosomes do bacteria have?
80S ribosomes composed of a 60S large subunit and a 40S small subunit
Fill in the blank: The assertion that ‘life only comes from life’ was stated by Louis Pasteur in regard to his experiments that definitively refuted the theory of _______.
spontaneous generation
John Snow is known as the Father of _______.
epidemiology
What theory states that disease may originate from proximity to decomposing matter and is not due to person-to-person contact?
miasma theory
Who was the scientist that first described cells?
Robert Hooke
Explain in your own words Pasteur’s swan-neck flask experiment.
Pasteur demonstrated that microorganisms in the air contaminate sterile solutions, disproving spontaneous generation.
Why did the experiments of Needham and Spallanzani yield different results?
Needham’s experiments allowed air exposure, while Spallanzani sealed his flasks, preventing contamination.
How did the explanation of Virchow and Remak for the origin of cells differ from that of Schleiden and Schwann?
Virchow and Remak proposed that cells arise from pre-existing cells, while Schleiden and Schwann suggested cells were the basic unit of life.
What evidence supports the endosymbiotic theory?
Mitochondria and chloroplasts have their own DNA, ribosomes, and reproduce independently.
What were the differences in mortality rates due to puerperal fever that Ignaz Semmelweis observed?
Mortality rates were higher in clinics where doctors did not wash hands compared to midwives’ clinics.
How did Semmelweis propose to reduce the occurrence of puerperal fever?
He proposed hand washing with chlorinated lime solution.
What is the direction of water flow for a bacterial cell living in a hypotonic environment?
Water flows into the cell.
How do cell walls help bacteria living in hypotonic environments?
Cell walls prevent bursting from osmotic pressure.
How do bacterial flagella respond to a chemical gradient of an attractant?
They rotate counterclockwise to move toward a higher concentration.
Fill in the blank: Mitochondria in eukaryotic cells contain ribosomes that are structurally similar to those found in _______.
prokaryotic cells
What are prokaryotic cells that are rod-shaped called?
bacilli
The type of inclusion containing polymerized inorganic phosphate is called _______.
metachromatic granules
Peroxisomes typically produce _______ that helps break down molecules.
hydrogen peroxide
Microfilaments are composed of _______ monomers.
actin
What existing evidence supports the theory that mitochondria are of prokaryotic origin?
Similarities in DNA and ribosomal structures between mitochondria and bacteria.
Why do eukaryotic cells require an endomembrane system?
To compartmentalize cellular functions.
Name at least two ways that prokaryotic flagella are different from eukaryotic flagella.
- Prokaryotic flagella are simpler in structure
- Prokaryotic flagella rotate, while eukaryotic flagella whip
Why are mitochondria and chloroplasts unable to multiply outside of a host cell?
They rely on host cellular machinery for replication.
