PNB 2250 Exam 1 Study Set Questions
and Answers 100% Pass
Animals Traits - ✔✔-distinguish them from plants and single cell organisms
-eukaryotic, multicellular, complex tissues, differentiated tissues
-heterotrophic: consume living or dead plants or animals
-movement or sessile (stuck to something)
Advantages of Multicellularity - ✔✔1. Cells dedicated to specific tasks, increase in
efficiency
2. Not all genes expressed, saves energy
3. Cells farther away from surface (easier to maintain homeostasis)
***Benefits outweigh cost
Disadvantages of Multicellularity - ✔✔1. Need cell-to-cell connections
2. Need cell-to-cell communication
3. Need system to distribute nutrients
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,3. Must develop tissues and organs to more effectively regulate internal and external
processes
Limitations of the Fossil Record - ✔✔1. Loss of soft tissues, loss of DNA
2. Biased-temporal (more recent fossils more likely found), geographical (movement of
Earth hides fossils, and taxonomic (marine animals fossilized near mud so more marine
fossils found)
Is genome size strongly correlated to organism complexity? - ✔✔No- it's how you use
the genes you've been given and which genes are turned on and off
Plants= 25,000 to 60,000 genes
Animals= 19,000 to 30,000 genes
Prokaryotes= 500 to 5,000 genes
Convergent Evolution - ✔✔Def: process by which unrelated organisms independently
evolve similarities (analogous structures) when adapting to similar environments;
shows LIMITED POSSIBLE SOLUTIONS TO PROBLEMS FACED BY ANIMALS (same
mutations can appear again and again in evolution)
Examples:
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, 1. Flight in insects- birds and bats
2. Fingerprints- humans and koalas
3. Opposable Thumb- opossums
4. Echolocation- bats, whales, shrews
How does Chemistry and Physics Affect Animal Development and Physiology? - ✔✔1.
Impact on animal form and function
2. All designs have advantages and disadvantages
3. Satisfaction of essential needs (energy input, waste removal, growth)
How Does Entropy Impact Animal Design? - ✔✔***CHONPS are 96% of body mass
-essential to work against entropy (disorder), stable bonds, allows you to make proteins,
lipids, and carbs, maintain strong structures resistant to entropy (hard to build but
effective)
Homeostasis - ✔✔Def: maintain internal environment suitable for life in the face of a
changing external environment
Examples of Homeostasis - ✔✔blood pH (change in physiological variable), blood
sugar/glucose(variable), body temperature, O2 levels, hormones, sweating, shivering
Ecosystem Engineering - ✔✔Def: engineer/modify living space to help suit it to
animal's needs
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and Answers 100% Pass
Animals Traits - ✔✔-distinguish them from plants and single cell organisms
-eukaryotic, multicellular, complex tissues, differentiated tissues
-heterotrophic: consume living or dead plants or animals
-movement or sessile (stuck to something)
Advantages of Multicellularity - ✔✔1. Cells dedicated to specific tasks, increase in
efficiency
2. Not all genes expressed, saves energy
3. Cells farther away from surface (easier to maintain homeostasis)
***Benefits outweigh cost
Disadvantages of Multicellularity - ✔✔1. Need cell-to-cell connections
2. Need cell-to-cell communication
3. Need system to distribute nutrients
Katelyn Whitman, All Rights Reserved © 2025 1
,3. Must develop tissues and organs to more effectively regulate internal and external
processes
Limitations of the Fossil Record - ✔✔1. Loss of soft tissues, loss of DNA
2. Biased-temporal (more recent fossils more likely found), geographical (movement of
Earth hides fossils, and taxonomic (marine animals fossilized near mud so more marine
fossils found)
Is genome size strongly correlated to organism complexity? - ✔✔No- it's how you use
the genes you've been given and which genes are turned on and off
Plants= 25,000 to 60,000 genes
Animals= 19,000 to 30,000 genes
Prokaryotes= 500 to 5,000 genes
Convergent Evolution - ✔✔Def: process by which unrelated organisms independently
evolve similarities (analogous structures) when adapting to similar environments;
shows LIMITED POSSIBLE SOLUTIONS TO PROBLEMS FACED BY ANIMALS (same
mutations can appear again and again in evolution)
Examples:
Katelyn Whitman, All Rights Reserved © 2025 2
, 1. Flight in insects- birds and bats
2. Fingerprints- humans and koalas
3. Opposable Thumb- opossums
4. Echolocation- bats, whales, shrews
How does Chemistry and Physics Affect Animal Development and Physiology? - ✔✔1.
Impact on animal form and function
2. All designs have advantages and disadvantages
3. Satisfaction of essential needs (energy input, waste removal, growth)
How Does Entropy Impact Animal Design? - ✔✔***CHONPS are 96% of body mass
-essential to work against entropy (disorder), stable bonds, allows you to make proteins,
lipids, and carbs, maintain strong structures resistant to entropy (hard to build but
effective)
Homeostasis - ✔✔Def: maintain internal environment suitable for life in the face of a
changing external environment
Examples of Homeostasis - ✔✔blood pH (change in physiological variable), blood
sugar/glucose(variable), body temperature, O2 levels, hormones, sweating, shivering
Ecosystem Engineering - ✔✔Def: engineer/modify living space to help suit it to
animal's needs
Katelyn Whitman, All Rights Reserved © 2025 3
