Properly identifying each species.
Accurately recording his findings.
Not interfering with ecosystem while studying the birds.
Answer:
Trophic level
Consumer
Producer
Explanation:
All living organisms require energy for their life processes, which they obtain by taken in food. In an ecosystem, this food is derived when organisms feed on each other. This process that eventually leads to a flow of energy within organisms is called FOOD CHAIN.
A food chain or food web always begins with a unique set of organisms called PRODUCERS. Producers are autotrophs capable of harvesting light energy from the sun and use it to produce their food (chemical) in a process called PHOTOSYNTHESIS. Other organisms called HETEROTROPHS feed on these producers to derive energy. In ecology, they are called CONSUMERS. Other consumers feed on the previous ones also to get energy.
Hence, each step of the food chain is occupied by organisms that obtain and store energy by feeding on another organism. This step is called TROPHIC LEVEL.
In a nutshell, a PRODUCER (usually plants) starts the food chain/web due to its photosynthetic ability. This producer gets eaten by an organism called CONSUMER and in the process, the energy and nutrient stored in the producers flows to the consumer. Another consumers feeds on the previous one and the energy keeps flowing. Each step of the food chain occupied by an organism that stores and transfers this energy is called TROPHIC LEVEL.
Frost wedging - water expands about 9% after freezing this pushes against the rock and fractures or breaks it open.
thermal expansion - <span>is the tendency of matter to change in shape, area, and volume in response to a change in temperature.</span>
traduce esto artículo
http://www1.lsbu.ac.uk/water/cellulose.html
The question is incomplete. Th ecomplete question is as following:
All of the following protect the skin and mucous membranes from infection EXCEPT
A) multiple layers of cells.
B) tears.
C) saliva.
D) HCl.
E) the "ciliary escalator."
Answer: D) HCl.
Explanation:
- The epidermis, the outer layer of the skin provides waterproofing and serves as a barrier to infection and other laers also sustain any type of injury.
- Tears wash out foreign bodies which enter the eye. In addition, tears contain a substance called lysozyme which has an antibacterial function and works to prevent microbial invasion and infection.
- Saliva protects against infection, especially via the innate immune system. This mechanism is an important first-line protection against bacterial and viral infection
- The mucociliar escalator is within the conducting airways and is composed of mucus and cilia that transfer the mucus up and out of the lungs where it can be removed by coughing or swallowing,
Whereas HCL helps in the digestion process.
Hence, the correct option is D.
