Biology-Ecosystems Essay

Submitted By sbuch03
Words: 1875
Pages: 8

PART A Question 1 (UB and IB) Complete the following table:
Ecosystem
Organism
ABIOTIC FACTOR
Measuring technique
Adaptation to overcome factor
BIOTIC FACTOR
Measuring Technique
Adaptation to overcome factor
Rocky Shore
Example
Limpet

eg temperature

eg thermometer hide under rock crevices to prevent overheating eg competition against other species for food using a quadrat to measure distribution and abundance efficient algae scraping device called a radula that aids in feeding

Barnacle

Harsh waves- Wave action
Observation
The shell allows waves to wash over easily over it so that it isn’t displaced. Also has the vacuum within the shell so it stays attached to the rock and helps maintain moisture when exposed. Predators
Using a quadrat to measure distribution and abundance
Barnacles have the ability to create a vacuum within it shell so it stays attached to the rock, making it extremely difficult for predators to try and get them off to eat them. (This ability also helps maintain moisture when exposed to sunlight.)

Algae

Exposure to sunlight
Observation
Algae absorb red wavelengths in shallow water, blue in medium depths and green light in deep waters. The interaction between the algae and sunlight takes another form.
The threat of predators
Using a quadrat to measure distribution and abundance
The reds, browns, yellows and green colours of algae blend it in with the colours of the ocean floor, in which they won’t be attacked or eaten by their predators.
Mangroves

Mudskipper

Temperature, humidity and salinity.
Thermometer and electrical conductivity metre
Leaves the water to allow its body to cool down through evaporation. If it losses too much moisture this way it will simply dive back into the water. This applies for the humidity and salinity.
Respiratory system

They have a network of capillaries just under their skin that allows the oxygen to diffuse into the blood and lets the carbon dioxide out. This kind of breathing is known as Cutaneous respiration. They also have a layer of mucous that protects their skin, minimising water losses and intakes.

Red Mangroves
Limited oxygen
Too much salt intake
Electrical conductivity metre
Red mangroves prop themselves above water level on stilt roots and absorb air through the pores in their back.
Red mangroves have the ability to exclude salt through a sort of ultrafiltration mechanism. This is possible because of their impermeable roots which are highly suberised.
Reproduction- Budding

The red mangrove can tolerate viviparous seedlings i.e. the seeds germinate and being to grow before the fruit has dropped from the tree. The seedlings tend to grow rapidly, getting to aout 6-12 inches.

Question 2A (IB) Complete the following table using camp booklet data obtained during the camp.

Abiotic Factor
MANGROVE
ROCKY SHORE

Paperbark
Casuarina
Mangrove
Riverbank
Rock Pool
Ocean
Salinity Less than 1% 1%
2%
Less than 1% 4%
4%
Temperature
19°C
19°C
19°C
21°C
19°C
18.5°C
Humidity
(% or low/med/high)
Medium
Medium
Low
Medium
Low
Low
Exposure to the wind
(1 – 10) 1 lowest
5
5
7
10
10
10
Canopy cover
40%
50%
15-20%
0%
0%
0% pH 6.7
6.5
6.6
7.2
6
6
Influence of tide (high/med/low)
Low
Low
Medium
High
High
High
Substrate/soil
Wet/muddy
Muddy
Muddy
Muddy but dried out in areas

Diversity of Organisms
(high/med/low)
High
High
Medium
Medium
High
High

Question 2B (IB) Design a “typical” food web for each ecosystem. Ensure that decomposers and detritivores are included. Use no more than 15 organisms in total for each ecosystem. All organisms must be Australian. Use the “Rocky Shore Ecology” Software to design your Rocky Shore food web

i.

ii.