1 - A ground level plant develops curling tendrils that wrap around other objects so it can "climb".
This is a species changing over time as it was originally a ground level plant but began to climb higher.
2 - Over many generations.
This is because diversity takes time and has to be integrated through generations; for instance, marriage. In a family, it becomes more diverse after the next generation as each generation is likely to marry someone of another ethnicity and allow the family tree to become more diverse.
3 - Mutate or Survive
It depends on what it means by mutate - develop a mutation to make it adaptable? If that's the case, then mutations within the DNA would be a result of adaptation and increase survival. Otherwise, survive is the obvious answer as adaption allows for species to move around and live longer.
Hope this helps!
I suggest you watch the Amoeba Sisters video again, 1-2x and take notes.
Biomagnification is when toxins / heavy metal are present in small amounts in fish, but accumulate as you move into higher trophic levels. This is one reason why it can be toxic for humans to eat tertiary or quaternary consumers, such as swordfish, shark, etc.
The correct answer is: A. Myofibrils contain thick and thin filaments.
Skeletal muscle cells are called muscle fibers because of their long and cylindrical shape. The plasma membrane of muscle fibers is sarcolemma, the cytoplasm is sarcoplasm, and the smooth endoplasmic reticulum sarcoplasmic reticulum (SR) Sarcoplasmic reticulum is specialized becaused it is involved in the process of contraction, so it stores, releases, and retrieves calcium ions.
The functional unit of a skeletal muscle fiber is the sarcomere which consists of highly organized contractile myofilaments actin that are thin filaments and myosin (thick filaments), together with other support proteins.