A muscle fiber contains many myofibrils, which are cylinders of muscle proteins. These proteins allow a muscle cell to contract. Myofibrils contain two types of filaments that run along the long axis of the fiber, and these filaments are arranged in hexagonal patterns. There are thick and thin filaments.hese proteins allow a muscle cell to contract. Myofibrils contain two types of filaments that run along the long axis of the fiber, and these filaments are arranged in hexagonal patterns. There are thick and thin filaments.
Cocklebur (Xanthium strumarium L.) is a large, annual broad-leaved weed with an erect, branched stem and broadly triangular leaves (Figure 1). The stem is rough-hairy, spotted with purple and up to 1.5 m high. The leaves are alternate on the stem, with toothed or lobed margins and rough-hairy surfaces.
Pillbugs, also known as sowbugs, or woodlice, are familiar backyard creepy crawlies to most of us. Pillbugs are correctly. classified as terrestrial Isopods, and belong to the Class Crustacea. Familiar crustaceans include lobsters, crabs, shrimp, and daphnia (water fleas).The crustaceans, in turn, are part of a larger group, Arthropoda, or jointed-legged animals.illbugs, also known as sowbugs, or woodlice, are familiar backyard creepy crawlies to most of us. Pillbugs are correctly. classified as terrestrial Isopods, and belong to the Class Crustacea. Familiar crustaceans include lobsters, crabs, shrimp, and daphnia (water fleas).