Ecology 2 - The Niche

Question 1

What is the niche

Answer 1

• Ecological space that an organism occupies
• Includes the habitat

Question 2

Explain the niche fully

Answer 2

• Defined by the organisms response to all factors that influence it
• Deals with performance

Question 3

Explain performance and the niche fully

Answer 3

• Performance / abundance on y-axis with evironmental gradient ( temp ) on x-axis
• Measured in terms of survival; growth and reproduction
• At peak = optimum temp can reproduce and survive as deer down graph, performance decreases

Question 4

What is net photosynthesis

Answer 4

• Is the difference in what the plant produces in photosynthesis and what it uses in respiration
• Contributes to growth

Question 5

How are rocky shores studied

Answer 5

• Go down to shore at low tide at top of shore and take a shore profile
• Place quadrats and count number of species in block ending up with a shore profile

Question 6

Explain shore zonation

Answer 6

• AKA shore profile
• Has diffrenet bands at top of shore compared to bottom of shore
• Littorina zone ( seaweed ) at top then upper balanoid ( barnacles ); lower balanoid ( seaweeds ); cochlear ( limpet ) and then infratidal

Question 7

Why do we get zonation bands

Answer 7

Because of the sun

Question 8

Why do planets orbit sun

Answer 8

Gravity between sun and earth which is weaker than the force between earth and the moon

Question 9

How long does it take the moon to orbit the earth

Answer 9

+- 28 days

Question 10

What is subject to gravitational pull on earth

Answer 10

Water

Question 11

Explain high tides

Answer 11

• Happens twice a day
• 8am and 8pm
• Moon and sun in alignment and earth is between them thus the water bukges on either side

Question 12

When does spring tides occur

Answer 12

When moon and sun are in alignment and pull in smae direction

• High tides are highest during spring tides, which occur during full and new moons, not 14 days after.

Question 13

Explain New moon

Answer 13

• 14 days after spring tide when moon has moved to the side
• Thus moon and sun arent in alignment and pull in opposite directions
• Difference in low and high tide is less neap tides

Question 14

Explain heoght above chart datum

Answer 14

• MTL - Mean tide level
• MLWN - Mean low water neap
• MLWS - mean low water spring
• MHWS - Mean high water neap
  -MHWN - mean high water sprin

Question 15

Explain the shore for marine animals

Answer 15

Top of shore = very stressful beacuse its hot and dry compared to the bottom

Question 16

What are tide levels influenced by

Answer 16

Amount of wave exposure

Question 17

Explain animals being displaced on the shore

Answer 17

• Need to be able to find their way back to their zone if displaced
• Use responses to light and gravity
• If washed to bottom of shore = use negative geotaxis

Question 18

Explain shells and the shore

Answer 18

Top of shore = tall; spire shell as has less surface area for radiation

• Flat shell = recieces lots of radiation
• SMooth; flat shell with lasrge foot = more conduction; more radiation and le re-radiation than a corrugated shell with large foot but is more re-rediate