How does skeletal tissue protect the brain?

Skeletal tissue constitutes the structural framework of the animal body, holds the muscles, and protects the internal organs from injury. The brain is the most sensitive and important part of the body of vertebrate animals. So, its protection demands the highest importance. There is a cover made up of hard bones around the brain known … Read more

What is muscle tissue?

The tissue having the capacity of contraction and expansion is known as muscle tissue. It originates from the mesoderm of the embryo and regulates the movement of the organs and the organism. The cells of muscle tissue are elongated and myofibrils are present in them. Matrix generally remains absent in this tissue.

Why are plastids called colour forming organs?

The coloured organelles present within the cytoplasm of plant cells are known as plastids. They are responsible for the formation of color of any plant part like leaves, flowers, and fruits. In absence of light plastids are known as leucoplasts become colorless. The colorless plastids are known as leucoplasts generally present in the cell of … Read more

What is plasmalemma?

The protoplasm of the living cell remains surrounded by a bi-layered selectively permeable membrane known as plasmalemma or cell membrane. “Plasmalemma” is another, less common term for the cell membrane or plasma membrane. It functions as the outermost boundary of all living cells, separating the interior (cytoplasm) from the external environment. Here’s a closer look … Read more

What is an ion?

Compounds composed of metals and nonmetals contain charged species. The charged species are known as ions. An ion is a charged particle and can be negatively or positively charged. A negatively charged ion is called an ‘anion’ and the positively charged ion, a ‘cation’. Take, for example, sodium chloride (NaCl). Its constituent particles are positively … Read more

Molecules of elements

The molecules of an element are constituted by the same type of atoms. Molecules of many elements, such as argon (Ar), helium (He), etc. are made up of only one atom of that element. But this is not the case with most of the nonmetals. For example, a molecule of oxygen consists of two atoms … Read more