Answer:
There is no video but ecological relationship will be defined on a general note and it is not always beneficial to organisms.
Explanation:
In an ecosystem, organisms of the same or different species tend to interact with one another. This interaction is referred to as ECOLOGICAL RELATIONSHIP between the involved organisms. An ecological relationship can be of different types depending on the effect.
SYMBIOSIS is an ecological relationship between two organisms that interact together. SYMBIOSIS can either be mutualistic (both organisms benefit), parasitic (one organism loses and one gains), or commensalistic (one organism benefits and one neither benefits or loses). Another ecological relationship is PREDATION, where one organism called the PREDATOR feeds on part or all of another organism called PREY in order to obtain energy.
As stated above, some of the organisms involved in an ecological relationship benefits while others lose. Hence, it is not always a beneficial relationship to organisms.
Answer:
The answer should be 
Since the pedigree has two different letters, it will have one letter of each, but the DNA will still be A.
Answer: An object with twice the mass of another object will weigh twice as much is the statement accurately describes the relationship between mass and weight.
Hope it helps you if not sorry
Explanation: A.Mass is an objects weight multiplied by the amount of gravitational force acting upon the object
Answer:
The correct answer is D. levator scapulae.
Explanation:
The levator scapulae is the muscle involved in the scapula lifting, as it's located on the sides and back of the neck. As the person's head is protruding forward it's highly possible that the muscle involved is the <em>levator scapulae. </em>
Answer:
Carbon dioxide
Explanation:
The alveoli picks up the oxygen you breathe in and releases the outgoing waste product carbon dioxide