Ecology

What are the three categories of adaptations?

Structural (physical features), Behavioral (actions/conduct), and Functional (internal processes/metabolism).

Give an example of a functional adaptation in a desert animal.

Producing highly concentrated urine to conserve water and having a metabolism that produces water from fat breakdown.

What is an extremophile and where might they live?

An organism adapted to survive in extreme conditions, such as high pressure (deep sea), high temperature (volcanic vents), or high salinity (salt lakes).

What are the four main abiotic factors that affect plant distribution?

Light intensity, temperature, moisture levels, and soil pH/mineral content.

What are the four main biotic factors that can disrupt an ecosystem?

Availability of food, new predators arriving, new pathogens/diseases, and competition between species.

Define 'interdependence' in a stable community.

When species rely on each other for food, shelter, pollination, and seed dispersal

How do you calculate the estimated population size using a quadrat?

(Total area / area sampled) x number of organisms counted in the sample.

What is the specific use of a transect line?

To investigate the change in distribution of a species across a specific environmental gradient (e.g., moving away from a hedge).

What are the three main processes that return CO2 to the atmosphere?

Respiration (all living things), Combustion (burning fossil fuels/wood), and Decay (microorganisms respiring).

What is the only process that removes CO2 from the atmosphere?

Photosynthesis by green plants and algae.

Why is high biodiversity crucial for the survival of ecosystems?

It reduces the dependence of one species on another for food and shelter, making the ecosystem more resilient to changes.

How does pollution in water reduce biodiversity?

Fertilizer runoff causes eutrophication (algal blooms), leading to oxygen depletion and the death of aquatic organisms.

What are the two main gases contributing to the enhanced greenhouse effect?

Carbon dioxide (from combustion/deforestation) and Methane (from rice paddy fields and cattle farming).

What are four major consequences of global warming?

Rising sea levels (melting ice/thermal expansion), extreme weather events, altered migration patterns, and loss of habitats/extinction.

Why is peat bog destruction a 'double hit' for global warming?

1. Burning or decaying peat releases stored CO2. 2. The destruction of the bog removes a vital carbon sink.

How can humans maintain biodiversity?

Breeding programs for endangered species, protection of rare habitats, reintroduction of field margins/hedgerows, and recycling resources.

What is the definition of a 'trophic level'?

The position an organism occupies in a food chain (Level 1 is always producers).

What do apex predators represent in a food chain?

Carnivores at the top of the food chain that have no natural predators.

How do decomposers break down organic matter?

They secrete enzymes onto dead matter to break it down into small soluble food molecules, which then diffuse into the microorganism.

Why is only about 10% of biomass transferred to the next trophic level?

Losses due to: 1. Not all of the organism being eaten. 2. Some is lost as waste (feces/urea). 3. Large amounts used in respiration/heat.

What is the formula for efficiency of biomass transfer?

(Biomass transferred to next level / Biomass available at previous level) x 100.

What are the requirements for sustainable food security?

Maintaining soil health, efficient biotechnology, sustainable fishing (quotas/net size), and reducing food waste.

What is 'Fusarium' and how is it used in biotechnology?

A fungus used to produce Mycoprotein (a protein-rich meat substitute) grown in fermenters using glucose syrup and aerobic conditions.

How can GM (genetically modified) crops help food security?

They can be engineered to be drought-resistant, have higher yields, or contain extra nutrients (like Golden Rice).

What is the 'time lag' in a predator-prey cycle?

The delay between the prey population increasing and the predator population subsequently increasing (due to time needed for reproduction).

What is biogas and how is it produced?

A renewable fuel (mostly methane) produced by the anaerobic decay of organic waste, such as sewage or animal manure, using bacteria in a generator.

Why is biogas production temperature-sensitive?

The bacteria involved require an optimum temperature for their enzymes to work