Final Exam

Question 1

What are the defining characteristics of all animals?

Answer 1

• Domain Eukarya; Kingdom Animalia
• Multicellular w/ well developed tissues (except sponges)
• Heterotrophic by ingestion/absorption (fungi)
• Internal digestive cavity
• Capable of movement, though some move then anchor themselves for the rest of life

Question 2

Which traits allow animal groups to differentiate?

Answer 2

1. Does the animal have true tissues?
   - cells are coordinated
   - cells are NOT coordinated
2. What type of symmetry?
   - radial: multiple planes divide
   - bilateral: only one plane
3. Which direction does gut form?
   - protosome: mouth first, gut from front to back
   - deuterosome: anus first, gut from back to front
4. Does the animal molt as it grows?
   - shedding of exoskeleton

Question 3

What are the 9 major animal phyla?

Answer 3

1. Chordates (lizards, humans)
2. Echinoderms (starfish, sea urchins)
3. Arthropods (scorpion, millipede)
4. Roundworms (hookworm, heartworm)
5. Molluscs (octopus, snails)
6. Annelids (earthworm, leach)
7. Flatworms (tapeworm, fluke)
8. Cnidarian (jellyfish, hydra)
9. Sponges

Question 4

What features set the chordates apart?

Answer 4

1. Notocord: rod of tissue for support
2. Dorsal, hollow nerve cord: forms central nervous system
3. Gill pouches or slits
4. Postanal tail

• All features are present in embryos but may or may not persist into adulthood.

Question 5

What are the vertebrate groups?

Answer 5

1. Lampreys
2. Cartilaginous Fishes
3. Ray-finned Fishes
4. Lobe-finned Fishes
5. Amphibians
6. Reptiles and Birds
7. Mammals

Question 6

What are the three groups of mammals?

Answer 6

1. Monotremes (lay eggs; no nipples, just hair; only 5 species)
2. Marsupials (short womb time; pouch; about 300 species)
3. Placentals (full womb time; about 4500 species)

Question 7

Understand all major evolutionary adaptations

Answer 7

1. True tissues
2. Symmetry (bilateral, radial)
3. Gut (deuterosome - butt; protosome - mouth)
4. Molting
5. Vertebrae
6. Jaws & fins
7. Lungs
8. Four legs
9. Amniotic egg
10. Feathers
11. Hair, long legs, mammary glands

Question 8

Define a population

Answer 8

A population is a group of the same species interacting in a local environment

Question 9

What is population ecology?

Answer 9

the study of populations in relation to their environment

Question 10

What is exponential growth?

Answer 10

J-shaped curve shows that growth is constantly trending upwards in an unlimited environment.

Question 11

What is carrying capacity?

Answer 11

Carrying capacity refers to the environmental factors that influence ability to support certain population sizes.

Question 12

What can limit exponential growth?

Answer 12

carrying capacity and natural disasters

Question 13

How does carrying capacity affect logistic growth?

Answer 13

It stabilizes the population size

Question 14

What is a biological community?

Answer 14

An assembly of various populations living close enough to have potential interactions

Question 15

Define the various species interactions, cite examples of each

Answer 15

1. Competition
   - [-/-] interaction
   - Two species compete for same resource, not enough for both
   - Competitive Exclusion Principle: one will outcompete the other
   - Resource Partitioning: no two species can occupy the same niche; some overlap possible
   - Examples: lion and cheetah; tall and short trees
2. Predation
   - [+/-] interaction
   - Claws, teeth, fangs, stingers and poision are important adaptations that enable this
   - Strong selective pressure on prey
   - Prey have developed defenses
   - Example: fox and rabbit; spiders and flies
3. Parasitism
   - [+/-] interaction
   - Parasite derives nutrients from host
   - Host often harmed/killed in the process
   - Examples: malaria, cordyceps fungus, european cuckoo
4. Mutualism
   - [+/+] interaction
   - Both species benefits
   - Species can be dependent or independent of one another
   - Examples: probiotic bacteria & animals, bees & flowers
5. Commensalism
   - [+/0] interaction
   - One species benefits
   - Other is neither helped or harmed
   - Very hard to classify
   - Examples: egrits & cattle, spider & frog
6. Facilitation
   - [+/+ or 0/+] interaction
   - One species has positive effect on another
   - However, no direct contact!
   - Examples: black rush,

Question 16

What are the various defense strategies employed by prey?

Answer 16

• Behavioral: hiding, fleeing, herding, projectile vommit, blood squirts, alarm calls
• Mophological and physiological: colaposematic coloration, camouflage
• Mimicry: Batesian, where harmless species mimics harmful one. Mullerian, where two harmful species resemble each other.
• Mechanical: spikes, tough shell, urdicating hairs, quills
• Chemical: cloud of ink, toxic secretions, poison skin, skunk spray, acid firing

Question 17

What is the difference between primary and secondary succession? In which situations would each occur?

Answer 17

Difference is whether soil exists or not. Secondary succession also much more common. Primary succession occurs when there is no soil, secondary succession occurs after major damage occurs but soil still remains.

Question 18

Examples from the Challenges of Life video clip

Answer 18

Raising Offspring

• Giant pacific octopus, finds nesting place, hatches offspring then dies
• Red poison dart frog takes tadpoles on back to find small pools of water atop bromeliad plants and feeds unfertilized eggs to them
• Chinstrap penguins must learn to swim and feed on their own at early age
• Orangutans will raise young for 8 years

Eating

• Bottlenose dolphins kick up dust cloud with tails to entrap fish for feeding
• Cheetahs work in groups to take down large prey they cannot do alone
• Chameleons use camo to get up close to prey
• Flying fish can travel up to 200m in the air to avoid predators
• Brown tufted capuchins eat tough nuts by peeling off fiber skin, letting dry, then cracking nut with rocks

Reproduction

• Stalk-eyed fly pumps air into head to extend eye stalks. Widest one wins!
• Male hippos fight one another for mating rights
• Grebes (bird) renew vows every year through mimicking and dancing, only strongest and ost faithful remain together.

Question 19

What is an ecosystem?

Answer 19

An ecosystem consists of all living (biotic) and non-living (abiotic) factors that coexist and interact in a given community

Question 20

How does energy flow through and nutrients cycle through an ecosystem?

Answer 20

Energy from sun is captured by primary producers and converted to chemical energy. Primary consumers eat primary producers, Secondary consumers eat primary ones, and tertiary consumers eat secondary ones. Nutrients cycled back after organisms die by decomposers.

Question 21

How do the laws of thermodynamics relate to energy flow in an ecosystem?

Answer 21

1st LoT: energy captured from sun is conserved and lost from organisms as heat.
2nd LoT: energy conversions are not 100% efficient, some is always lost as heat.

Question 22

What is a trophic level?

Answer 22

Position in food chain relative to energy source

Question 23

What is trophic efficiency?

Answer 23

percentage of energy transferred to next trophic level

Question 24

Why is only 10% of the energy at one trophic level available to the next?

Answer 24

50% is lost as heat and feces
40% goes to cellular respiration
10% remains for biomass (new growth)

Question 25

What is the ultimate fate of energy reaching Earth?

Answer 25

It is lost as heat, it is not recycled back to the sun.

Question 26

How would global vegetarianism among humans impact available energy?

Answer 26

There would be more energy available as not as much needs to go into the food chain before it reaches us.

Question 27

How does the law of conservation of mass relate to nutrient cycling?

Answer 27

Matter can neither be created or destroyed, hence nutrients are continually recycled within the biotic and abiotic components of ecosystems.

Question 28

What is the general pattern of biogeochemical cycle?

Answer 28

1. autotrophs take in inorganic carbon (CO2)
2. Use CO2 to produce sugars (glucose)
3. Heterotrophs use glucose to produce tissues (glycogen).
4. Repeated all the way to the top of the food chain.
5. Decomposers release elements from waste or dead material back into environment as CO2.

Question 29

Explain the carbon cycle in detail.

Answer 29

Inorganic carbon in the form of CO2 in the atmosphere is used by primary producers in photosynthesis, converting the carbon to an organic form, sugar, which is later used by all consumers through the food chain. Organic carbon is returned to the atmosphere by the decomposition of organic material, burning of fossil fuels and cellular respiration.

Question 30

What are three ways to define biodiversity?

Answer 30

1. Genetic: genetic differences within and between populations
2. Species: variety of species in an ecosystem (most common, popular)
3. Ecosystem: variety of ecosystems

Question 31

In what ways does biodiversity impact humans?

Answer 31

• Biophilia (like living amongst living things)
• Pharmaceutical uses
• Ecosystem services

Question 32

What are some ecosystem services and why are they important?

Answer 32

Purification of water/air, cycling of nutrients, detoxification/decomposition of wastes, pollination.

Can be done much more efficiently at scale and best of all, FREE!

Question 33

Describe the patterns of loss of diversity (extinction).

Answer 33

Background extinctions are considered normal and account for about 10%of species loss over time. Mass extinctions occur once in long time, but cause a tremendous loss in species. There is concern that the current background extinction rate is on the rise (20-30%) leading researchers to ponder whether another mass extinction event is on the horizon.

Question 34

What are the major threats to biodiversity?

Answer 34

1. Habitat destruction
   - considered greatest threat
   - also habitat fragmentation
   - in ohio: wetlands, prairies, forests, riparian habitats
   - coral reefs
2. Invasive species
   - introduced by accident or intentionally
   - grow unimpeded due to lack of natural controls (predators, disease, etc.)
   - 3 characteristics: voracious appetite, protected from predation, crazy reproduction.
3. Overharvesting
   - affects both plants and animals
4. Global change
   - climate, acid rain, atmospheric CO2

Question 35

What is the difference between ozone problem and global climate change?

Answer 35

The depletion of the ozone layer is bad for the planet because it absorbs UVB radiation that is harmful to life (though ozone gas itself is harmful to humans).

Global climate change refers to the average temperature rise on Earth, which is being affected by excessive amounts of atmospheric CO2 trapping excess heat.

Question 36

Explain why the phrase “global warming” does not adequately describe issue of climate change.

Answer 36

Because the rise of temperature is not uniform across the globe. The effects of the rise in average temperature can be felt more in the arctic than in the tropics.

Question 37

What are some important influences on biodiversity?

Answer 37

• Access to sunlight: more sunlight = more energy for life = more species
• Evolutionary History of Area: the more stable an area the more likely for biodiversity. No major events to wipe out populations
• Rate of Disturbance: How frequent disturbance affects survivability of species. Intermediate Disturbance Theory says too much disturbance causes low diversity, but so does low b/c superior species can outcompete lesser ones.

Question 38

What is restoration ecology?

Answer 38

The practice of restoring degraded ecosystems to a more natural state by speeding up recovery. Very difficult to return to exact pristine state prior to destruction. Still takes a very long time and results not guaranteed.

Question 39

What are the major limitations to growth in the tropics?

Answer 39

Deforestation and deprived soils from agriculture and farming.

Question 40

What is an Al-accumulator? How could it be used in a restoration context?

Answer 40

A plant that is able to absorb and retain aluminum from soil. Al is not good for plants because it is toxic to plants and makes the soil acidic.

Question 41

What is a N-fixer? How could it be used in a restoration context?

Answer 41

A plant that is able to extract nitrogen from the atmosphere and return it to the deprived soil where it can be used by other plants.

Question 42

What were the results of the study described?

Answer 42

The results were largely inconclusive. The introduction of Al-accumulator and N-fixer did not improve soil acidity or nutrient levels for the plant in question. There was some improvement of soil temperatures.