Answer:
mutation
Explanation:
A mutation is a random change to genetic material. ... If a mutation occurs in a gene that results in a change to the sequence of DNA bases, then the structure of the protein that is made may also be altered. This could alter an individual's phenotype
Answer:
B. Cartilaginous fish
Explanation:
Sharks have a cartilaginous skeleton. Cartilage is less dense than bone which allows sharks to move quickly through the water without using too much energy.
Answer:
oxygen
Explanation:
A limiting factor is any condition whose decrease, increase, absence or presence is able to limit/stop population growth. Examples of limiting factors include abiotic conditions (e.g., temperature, water, oxygen, CO2, etc) or biotic conditions (e.g., food, mate, etc). There are many aquatic species that require high levels of oxygen (e.g., fish), thus being it a limiting factor for these species.