Ecology

Question 1

What is an ecosystem?

Answer 1

interaction between biotic and abiotic communities

Question 2

What is a biome?

Answer 2

• ecosystem within a specific geographical region

Question 3

Where does evolutionary origin of plants and animals trace to?

Answer 3

the seas

• they must colonize land and adapt to
• – lack of water, food, varying temperatures, varying composition of soils

Question 4

What are the 8 terrestrial biomes? (in order from equator to poles)

Answer 4

• desert
• grassland
• rainforest
• temperate deciduous
• temperate coniferous
• taiga
• tundra
• polar

Question 5

Desert Biome

Answer 5

• very little rain

Question 6

Grassland biome

Answer 6

• low rainfall
• no shelter for herbivores
• long legged and hooved animals
• prairies

Question 7

Rainforest biome

Answer 7

• jungles, torrential rainforests (lots of rain)
• temperate vs tropical (tropical high temp)
• dense vegetation
• epiphytes (plants grow on each other) and saprophytes (live off dead matter)

Question 8

Temperate deciduous forest

Answer 8

• cold winters, warm summers, moderate rain

Question 9

Temperate coniferous forest

Answer 9

• cold, dry

- beavers, bears, conifers

Question 10

Taiga

Answer 10

• long, cold winters
• thin soil
• coniferous trees
• extreme northern Canada and Russia

Question 11

Tundra

Answer 11

• treeless
• frozen plain
• permafrost (covered ground with snow and ice)

Question 12

Polar region

Answer 12

• polar ice caps

- no vegetation

Question 13

Marine Biomes

Answer 13

• nutrient materials and dissolved salts

- ocean conditions are more uniform than land

Question 14

Marine Biome Zones

Answer 14

• intertidal zone: low tides that undergoes variations in temperature and dryness

Question 15

Necritic Zone

Answer 15

• part of continental shelf that contains ocean with 600 ft deep

Question 16

Pelagic Zone

Answer 16

• open ocean
  Photic and Aphotic Zone
  Photic: sun lit
  Aphotic: no sunlight, no photosynthesis (nekton and benthos)

Question 17

Freshwater biomes

Answer 17

• rivers, lakes, ponds, marshes etc
• currents exist! therefore need muscle/holdfasts
• variations in climate and water (freeze/dry up)

Question 18

What is usable nitrogen in the form of?

Answer 18

nitrAtes
- converted from elemental nitrogen (which is inert) to nitrAte via
nitrogen fixing bacteria and lightning

Question 19

Usable nitrAtes travel through the nitrogen cycle … describe the pathway.

Answer 19

• Nitrates are absorbed by plants
• proteins produced
• animals eat the proteins

Question 20

What is nitrate converted to in the nitrogen cycle?

Answer 20

Ammonia (NH3) is released by bacteria of decay.

Nitrogen (as nitrate) locked up in dead plants/animal proteins converted to ammonia

Question 21

What are the fates of ammonia?

Answer 21

• nitrified to nitrItes

- denitrified / broken down to free nitrogen

Question 22

What are nitrites used for?

Answer 22

• chemosynthetic bacteria: breaks down ammonia to nitrite and further broken down to nitrAte and absorbed by green plants (cycle happens again)

Question 23

Explain the process of the carbon cycle:

Answer 23

• plants use gaseous CO2 to produce glucose
• animals eat plants and use the digested nutrients to form carbs, fats, proteins etc
• CO2 is metabolically produced CO2 and released back to the air

Question 24

Symbiosis:

Answer 24

• live together in association and may or may not be beneficial to participants

Question 25

Cooperation:

Answer 25

species and embers of same species must cooperate; protect each other and acquire resources

Question 26

What is external fertilization and is it sexual or asexual reproduction?

Answer 26

asexual reproduction
- fusion of female and male gametes when female deposits her eggs and male gametes fertilize somewhere in the environment

Question 27

What is double fertilization and where does it occur in?

Answer 27

• union of two sperm cells with two cells of the embryo sac

- occurs in MOSTLY angiosperms and some gymnosperms