Biology Revision - Energy And Biomass In Food Chain

In a food chain, the primary producer is the plant that produces its own food through photosynthesis. The herbivore is the primary consumer that feeds on the plants. Therefore, the missing term would be the secondary consumer, which is the carnivore that feeds on the herbivores. Carnivores are animals that primarily eat meat, completing the food chain by consuming the primary consumers.

Energy losses are mainly due to waste products such as faeces and urine. Not all food is fully digested and absorbed by the body, so some of it is lost in the form of waste. This means that the energy contained in the undigested food is not utilized by the body and is instead excreted. Therefore, waste products contribute to energy losses in the overall system.

As you move up the trophic levels in a food chain, there is typically a decrease in the number of organisms. This is because energy is lost as it is transferred from one level to the next. The primary producers, such as plants, convert sunlight into energy through photosynthesis. However, only a small fraction of this energy is consumed by herbivores, such as rabbits, which in turn provide energy to their predators, like foxes. Therefore, each trophic level has fewer organisms than the previous one, resulting in a decrease in the number of organisms as you move up the food chain.

The explanation for the correct answer, biomass, is that it refers to the total mass of living organisms in a given area or ecosystem. In this scenario, the number of organisms alone does not accurately represent the amount of energy available for each level of the food chain. Biomass takes into account the size and weight of the organisms, which is a more reliable indicator of the energy available for consumption. Therefore, when considering the flow of energy through a food chain, it is often better to look at biomass rather than the numbers of organisms.

In a food chain, the primary producer is the plant that produces its own food through photosynthesis. The herbivore is the primary consumer that feeds on the plants. The carnivore is the secondary consumer that feeds on the herbivore. Therefore, the next consumer in the food chain after the carnivore is the tertiary consumer.

The correct answer is "total mass excluding water." This refers to the mass of an object or substance without the presence of water. It represents the dry weight or mass of the material after any water content has been removed. This measurement is often used in various scientific and industrial applications to determine the true weight or mass of a sample without the interference of water.

In the context of food chains, a plant is considered a primary producer. This is because plants are able to produce their own food through the process of photosynthesis, using sunlight, water, and carbon dioxide to produce glucose and oxygen. They are at the beginning of the food chain, as they serve as a source of energy for other organisms. Therefore, the correct answer is "producer".

The energy losses mentioned in the question are mainly due to waste products such as faeces and urine, which are not fully digested and absorbed by the body. However, in warm-blooded animals, another significant energy loss is through the production of heat, which is generated through the process of respiration. This heat production is necessary for maintaining a constant body temperature, but it also represents an energy loss that is not fully utilized by the organism.

Respiration is the process by which glucose is broken down to release energy. Glucose is a carbohydrate molecule that serves as the primary source of energy for cells. Through a series of biochemical reactions, glucose is oxidized, releasing energy in the form of ATP (adenosine triphosphate). This energy is then used by the cell for various metabolic processes, such as muscle contraction, active transport, and synthesis of molecules. Therefore, glucose is the correct answer for the given question.

The term "top" is used to describe the position of an organism in a food chain or food web. In this context, a "top carnivore" refers to an organism that is at the highest trophic level and feeds primarily on other carnivores or omnivores. These organisms are typically large predators and have no natural predators of their own. They play a crucial role in regulating the populations of lower trophic levels and maintaining the balance of the ecosystem.

In a food chain, plants are considered primary producers as they are able to produce their own food through photosynthesis. The next level in the food chain is occupied by primary consumers, which are organisms that directly consume plants for their energy and nutrients. Herbivores are a type of primary consumer as they exclusively feed on plant material. Therefore, herbivores are the correct answer for the missing term in the given question.

Animals require energy from respiration for movement. Movement involves the contraction and relaxation of muscles, which requires energy. This energy is produced through respiration, where glucose is broken down to release ATP, the energy currency of cells. Therefore, movement contributes to energy losses in animals.

The correct answer is "larger" because the question is asking about the biomass of the fox compared to the fleas. Biomass refers to the total weight of living organisms in a given area or ecosystem. Since the fox is larger in size than the fleas, it would have a greater biomass.

The term "wet mass" refers to the total mass of an object or organism when it is wet, which includes the mass of the water present. It is important to consider the water content when measuring the wet mass of something, as water can significantly contribute to the overall weight. Therefore, the correct answer is "total mass including water".

As you move up a trophic level in a food chain, there is a decrease in energy and biomass. This is because energy is lost as heat during metabolic processes and only a fraction of it is transferred to the next trophic level. Additionally, organisms at higher trophic levels require more energy to sustain themselves, resulting in less energy being available for growth and reproduction. Similarly, biomass decreases because each trophic level contains fewer organisms than the level below it, as energy is lost and not all of it is converted into new biomass.