The hypothalamus regulates the release of hormones from the pituitary gland, maintains body temperature, and organizes behaviors such as feeding, fluid intake, mating, and aggression. It is the central regulator of autonomic and endocrine visceral functions.
Options for the question have not been provided. They are as follows:
A. collagen fibers.
B. gelatinous mass.
C. actin and myosin fibers.
D. keratin fibers.
E. fibroblast cells.
Answer:
C. actin and myosin fibers.
Explanation:
Muscle cells or myocytes are unique because they have an abundant amount of actin and myosin fibers. These fibers are responsible for the contraction and relaxation of muscles. They are protein filaments, myosin is called thick filament and actin is called thin filament. Muscle cells not only have an abundant number of these fibers, but also they are organized properly in a fixed pattern. Each myosin is surrounded by actin and each actin is surrounded by myosin. They slide over each other in a fixed pattern to cause muscle contraction.
Energy is transfered from a molecule of sugar to atp by cellular respiration