Answer:
B.secrete hormones directly into the bloodstream
Multicellular organisms can be much larger and more complex. This is because the cells of the organism have specialised into many different types of cells such as nerve cells, blood cells, muscle cells all performing different functions.
Answer:
the thin filaments are pulled away from one another, thereby reducing their ability to interact with myosin
Explanation:
The myofibril is the basic unit of a muscle cell. Each myofibril is composed of contractile units known as sarcomeres which may contain two different types of myofilaments: thick myofilaments and thin myofilaments. The thick filaments are known to have a constant length, and they consist especially of myosin proteins. These filaments (thick) do not extend to the ends. On the other hand, the thin filaments extend in from each end, and they are mainly composed of actin proteins that serve as tracks for the movement of myosin proteins.