Animal Tissue Test - 7

The seed coat is fused with the pericarp in caryopsis. The caryopsis is popularly called a grain and is the fruit typical of the family Poaceae (or Gramineae), which includes wheat, rice, and corn.

Underground stems have distinct nodes and internodes. The nodes bear dry scale leaves with axillary buds. Terminal buds are also present.
Examples of underground stems include corms,rhizomes and tubers.

Antipodal cells and egg cell are haploid structures as they are formed after meiosis. Nucellus, megaspore mother cell and primary endosperm nucleus are diploid structures.

Epithelia are neither innervated by nerve cells nor pervaded by blood vessels due to lack of intercellular space.Epithelial cell sheets limit the movement of solutes through the intercellular space by forming tight junctions between adjacent epithelial cells, and therefore act as the major barrier between the internal and external environment of the body.

Erythrocytes are the red blood cells (RBCs). There are three types of blood cells: red blood cells, white blood cells, and platelets. RBCs are by far the most abundant type of cell in the human body, accounting for over 80 percent of all cells. Adult humans have somewhere around 25 trillion RBCs in their body, on average.

Skeletal muscle is unable to undergo a sustained contraction as it would lead to tetanus state of muscles.

Cartilage is classified in three types, elastic cartilage, hyaline cartilage and fibrocartilage, which differ in relative amounts of collagen and proteoglycan. Cartilage does not contain blood vessels (it is avascular) or nerves (it is aneural). Nutrition is supplied to the chondrocytes by diffusion.

Phloem is the conducting tissue, which is removed in girdling as it forms a part of the bark.

Many pitchers are lined with downward pointing hairs and waxy scales which cause prey to slip into the bottom of the pitcher. Prey are eventually broken down by digestive enzymes (such as proteases) which are secreted from the wall of the pitcher. Rainfall can accumulate in the bottom of the pitcher, creating a habitat for aquatic life, such as protozoa, mosquito larvae and even frogs (called a phytotelma).

Options 1, 2 and 3 are incorrect. The main constituent of the cellular tissue of the bone is ossein. Bone is highly vascular and its matrix occurs in concentric rings.
The osteocytes are the main bone forming cells. These osteocytes are irregular with off branches. Hence, option 4 is true.