08/02/2025, 17:18 Biology Paper III Essays - Evernote
Importance of different relationships between
organisms [25 Marker]
Importance of different relationships between organisms [25 Marker]
• Mycorrhizae
• Nitrogen Cycle
• Virus replication
• Succession
• Cholera within eukaryotic organisms
Evidence of the importance of relationships between organisms can firstly be
seen when looking at mycorrhizae and the symbiotic relationship they form
with plants. Mycorrhizae is a fungi which infects the roots of the plant
increasing the surface area of the roots by producing thin long strands known
as hyphae, so the rate of ion assimilation and water uptake increases providing
the plants with more nutrients. These nutrients (such as nitrates, K+, and
phosphorus from the soil) become incorporated into the plants biomass making
up their DNA, ATP, and proteins. This is vital as a plants growth is usually
inhibited by the concentration of ions present in its system as the nutrients are
used to produce the necessary reactants for cell division and DNA replication
allowing the plant to grow larger and be more successful. It would have more
leaves and therefore an increased rate of photosynthesis allowing it to grow
more once again and become more successful. In return the mycorrhizae
receives carbohydrates from the plant acting as their own food source. This is
important for plants specifically in nutrient poor soils; therefore, mycorrhizae is
found mostly in more intense environments where soils are less fertile and
abundant in nutrients. Desert plants are known to have many mycorrhizae
spreading deep and far into the soil in search of any nutrients to assimilate into
their biomass. The fungi also enhances disease resistance in the plant
protecting it from other invading species or pathogens as it acts as a physical
barrier alongside a chemical one with some mycorrhizae directly secreting
antimicrobial substances onto the plants roots.
In the nitrogen cycle the important interaction of various organisms can also be
seen. The process begins as nitrogen fixing bacteria convert nitrogen gas from
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Importance of different relationships between
organisms [25 Marker]
Importance of different relationships between organisms [25 Marker]
• Mycorrhizae
• Nitrogen Cycle
• Virus replication
• Succession
• Cholera within eukaryotic organisms
Evidence of the importance of relationships between organisms can firstly be
seen when looking at mycorrhizae and the symbiotic relationship they form
with plants. Mycorrhizae is a fungi which infects the roots of the plant
increasing the surface area of the roots by producing thin long strands known
as hyphae, so the rate of ion assimilation and water uptake increases providing
the plants with more nutrients. These nutrients (such as nitrates, K+, and
phosphorus from the soil) become incorporated into the plants biomass making
up their DNA, ATP, and proteins. This is vital as a plants growth is usually
inhibited by the concentration of ions present in its system as the nutrients are
used to produce the necessary reactants for cell division and DNA replication
allowing the plant to grow larger and be more successful. It would have more
leaves and therefore an increased rate of photosynthesis allowing it to grow
more once again and become more successful. In return the mycorrhizae
receives carbohydrates from the plant acting as their own food source. This is
important for plants specifically in nutrient poor soils; therefore, mycorrhizae is
found mostly in more intense environments where soils are less fertile and
abundant in nutrients. Desert plants are known to have many mycorrhizae
spreading deep and far into the soil in search of any nutrients to assimilate into
their biomass. The fungi also enhances disease resistance in the plant
protecting it from other invading species or pathogens as it acts as a physical
barrier alongside a chemical one with some mycorrhizae directly secreting
antimicrobial substances onto the plants roots.
In the nitrogen cycle the important interaction of various organisms can also be
seen. The process begins as nitrogen fixing bacteria convert nitrogen gas from
https://www.evernote.com/client/web#/notebook/6023ecd6-5695-e5af-51bd-423d67e1dfa4/note/95a4717e-737d-72c6-98e5-126dcb6ef17c 1/4