Lecture 3 Flashcards
Are prokaryotes considered to bbe evolved organisms?
they are highly evolved organisms
Why do we study prokaryotes?
- earliest form of life
- diverse and highly specialized
- abundant
- relatively simple organisms for various biological studies
- essential to biosphere functioning
- industrial potential
what is prokaryotes importance to humans?
- digestion
- diseases including superbugs (antibiotic resistance)
- environment
What are prokaryotes importance to humans?
- digestion
- diseases including superbugs (antiobiotic resistance)
- environment
What are the different shapes of prokaryotes?
- spherical
- rod shaped
- spiral
What are the biological characteristics of prokaryotes?
- unicellular and small (most)
- rigid cell wall
- DNA
- one double strand of DNA
- circular chromosome
- plasmids
- lacks nucleus
- generally lack other membrane bound organelles (except photosynthesizers)
- lack cytoskeleton
- smaller ribosomes than eukaryotes
- no sexual reproduction
- simple flagella common
What are biological implications of being microscopically small?
- rapid reproduction
- extensive easy dispersal
- intimate contact with surroundings implies high sensitivety to environment (and changes in it)
- high rate of living
- small size means water is extremely viscous
What does it mean that prokaryotes have a high rate of living?
small sized organisms have relatively high metabolic rates
What are the biological implications of being microscopically small?
- Rapid Reproduction: Microscopic organisms can reproduce quickly, facilitating population growth.
- Extensive Easy Dispersal: Being small allows easy dispersal through various environments.
- High Sensitivity to Environment: Microorganisms have intimate contact with surroundings, making them highly sensitive to environmental changes.
What does the “Everything is everywhere, but the environment selects” principle suggest?
The Baas-Becking hypothesis implies that microbes are ubiquitously distributed, but their survival and prevalence are determined by the specific environmental conditions.
How do microbes exhibit opportunism and dormancy in their life cycles?
Microbes can switch between opportunistic behavior, taking advantage of favorable conditions, and dormancy, a state of reduced activity during unfavorable conditions.
How is the ecology of prokaryotes closely linked to water availability?
- Direct Metabolic Demand: Water is essential for the metabolic processes of prokaryotes.
- Nutrient Supply: Water supplies nutrients necessary for microbial growth.
- Waste Removal: Water aids in the removal of metabolic wastes from prokaryotic cells.
Why do small-sized organisms exhibit a high ‘rate of living’?
Small-sized organisms have relatively high metabolic rates, leading to a faster pace of life processes.
What is the significance of small size in relation to water viscosity for microorganisms?
Passive Movement: Small size means most movement is passive in water flow.
Swimming Ability: Some microorganisms can swim, but typically only short distances (a few mm) due to the high viscosity of water.
What does high ‘rate of living’ mean?
High ‘rate of living’ refers to the metabolic activity rate of an organism. It is influenced by the surface area to volume ratio, where organisms with smaller ratios tend to have higher metabolic rates, while those with larger ratios exhibit slower metabolic rates.
How is the supply of nutrients, including carbon, vital in the context of energetics and nutrition?
The supply of nutrients, including carbon, is crucial for the metabolic process. Nutrients serve as building blocks and energy sources for various cellular activities.
What does restricted mobility imply for microscopically small organisms, specifically prokaryotes?
Restricted mobility implies that spatial and temporal heterogeneity in nutrients and the environment is crucial for prokaryotic activity. The inability to move freely necessitates reliance on localized resource availability.
What is the waste removal process associated with the given equation: CO₂(HCHO)ₙ + H₂O + Energy + O₂?
The given equation represents a simplified form of photosynthesis where carbon dioxide (CO₂) is converted into carbohydrate (HCHO) with the release of oxygen (O₂) and energy. This process involves waste removal and contributes to the overall energy balance in the cell.
How does surface area influence an organism’s ability to take up nutrients and release wastes?
Surface area determines the organism’s capacity for nutrient uptake and waste release. Larger organisms, like elephants, with lower surface area to volume ratios, have slower metabolic rates compared to smaller organisms, like mice, which have higher surface area to volume ratios, enabling faster metabolic rates.
How does the rigid cell wall of microbes impact their ability to acquire nutrients?
The rigid cell wall precludes phagocytosis in microbes, affecting their nutrient acquisition strategy.
What is the primary role of electron donor and acceptor compounds in the metabolic process?
Electron donor and acceptor compounds are essential for metabolism. They participate in oxidation/reduction reactions, enabling the transfer of energy to drive chemiosmosis.
How does the concept of scale describe the prokaryotic world’s resource distribution?
This concept highlights that resources for prokaryotic organisms are unevenly distributed, forming small islands or hotspots of activity amidst discontinuous environments.
How do prokaryotes mainly complete reproduction?
fission
Why do elephants and mice have similar total lifetime metabolic activity despite their lifespan difference?
Elephants and mice may have similar total lifetime metabolic activity, measured by the total number of heartbeats, despite their lifespan difference. This is because the surface area to volume ratio influences metabolic activity, with larger organisms having slower rates due to their restricted nutrient uptake caused by a relatively smaller surface area.
