Animal tissues are composed of sets of animal cells collected together. The structure of cells varies depending on their function. Therefore, the tissues are different and could be generally classified into four main kinds:

 

(i) Epithelial

Epithelial tissues form the protective coating and inner lining of the body and organs. They were the first to develop during embryonic development and the first to evolve during evolution. 

These tissues perform the following functions:

• • Help in the absorption of water and nutrients.

  • Form lining of blood vessels, alveoli, kidney tubules.

  • It forms a barrier to keep different body organ systems.

(ii) Connective

The embryo's mesodermal cells give rise to connective tissues. There are three components to these: Matrix of Intercellular Communication, mucopolysaccharide, and specifically hyaluronic acid.  These tissues perform the following functions:

• • bind structures together

  • store fat and transport substances

  •  form a framework and support for organs and the body system

(iii) Muscular

The embryo's mesoderm develops into muscle tissue.  Muscle tissue can be divided into skeletal muscle tissue, cardiac muscle tissue, and smooth muscle tissue.

 

Cardiac Smooth Skeletal Muscular Tissue performs the following functions:

• • Aids motility and mobility

  • Help keep the bones and other components in place

  • Controls peristalsis and parturition

(iv) Nervous

The peripheral and central nervous systems are composed of nerve tissue. Its main functions are as follows:

• • Neurons are the structural and functional building blocks of the nervous system. It is made up of three parts: an axon, a cell body, and dendrites.

  • Neuroglia is the brain and spinal cord cells that have specialized functions. They support neurons and fibres.

  • Neurosecretory cells serve as endocrine organs. Chemicals are released directly into the bloodstream by the axons.

 

The fundamental tissues present in organisms combine to create organs, which coordinate to create an organ system. In multicellular organisms, cells join together to form organ systems. Such a structure is crucial for more effective and well-coordinated tasks.

A body is made up of millions of cells. Every organ in our body is made up of one or more types of tissues. For instance, our heart comprises all four tissues, i.e., connective, epithelial, muscular, and neural tissues.

The diversity in organ and organ systems has a distinct pattern. This observable pattern

is referred to as an evolutionary tendency. An evolutionary tendency could be either a directional shift in a single lineage or a similar change across species, which means that multiple organisms undergo the same kind of change. Titanotheres, for example (a cool, extinct group linked to current horses and rhinos), show an evolutionary pattern.

Morphology is the study of shape or general physical attributes, especially and specifically in the case of plants or microorganisms. The term 'anatomy' is often used to study an animal's interior organs.

The earthworm is a red and brown terrestrial invertebrate that thrives in the wet soil's outermost surface. During the day, they reside in burrows created by burrowing and swallowing earth. Their fecal deposits, called worm castings, may be seen in gardens. Pheretima and Lumbricus are the most common types of earthworms found in Indian soil.

 

The earthworm's body wall is covered externally by a thin non-cellular cuticle, followed by the epidermis, two muscle layers (circular and longitudinal), and an innermost coelomic epithelium. The epidermis is composed of a single layer of columnar epithelial cells, including secretory gland cells.

 

The alimentary canal is a straight tube that connects the first and end segments of the body.

An earthworm’s body is long and cylindrical. It is split into several hundred short, identical segments (metameres numbering 100-110). The dorsal surface of the body is defined by a black median mid-dorsal line (dorsal blood vessel) running down the body's longitudinal axis.

 

Cockroaches are brownish or black-bodied creatures in the class Insecta of the phylum Arthropoda. Cockroaches with bright yellow, crimson, and green colours have also been found in tropical areas. Their size varies from 15 to 3 inches (0.6-7.5 cm). They feature a long antenna, legs, and a flat stretch of the top body wall covering the head. They are nocturnal omnivores that dwell in moist environments globally. They have infiltrated human houses and hence have become prevalent pests and disease carriers.

 

The adult body of the average cockroach, Periplaneta americana, is 33-53 mm long, with wings that reach past the tip of the abdomen in males. The cockroach's body is divided into three separate regions: the head, thorax, and abdomen. A tough, brown chitinous exoskeleton covers the whole body.

 

The alimentary canal is separated into three sections in the body cavity: foregut, midgut, and hindgut. The mouth opens into a small tubular pharynx, which leads to the oesophagus, a tiny tube conduit. This, in response, opens into a sac-like structure called a crop, which is used to store food.

 

Frogs are members of the class Amphibia of the phylum Chordata and can live on land and water. Rana tigrina is the most common frog species in India.

 

Frogskin is made of two layers: epidermis and dermis, which together include resident immune cells. The organ systems of frogs are quite well-developed. A bodily cavity houses its digestive, respiratory, circulatory, excretory, neurological, and reproductive systems. An alimentary canal and digestive glands make up the digestive system. The liver and pancreas are the two primary digestive glands in frogs. A DNA-bearing nucleus is seen in the middle of the cell in frogs. Amphibians have an uncommon circulatory system, with three chambers, two atria, and a single ventricle in their hearts. Frogs have a blood vascular system and a lymphatic system in their vascular system.

 

1. What are the key features of NCERT Solutions for Class 11 Biology Chapter 7?

NCERT Solutions for Class 11 Biology Chapter 7 is among the ideal resources for the CBSE Term – I exam preparation and other competitive exam preparation. These are its features:

• • A team of experts solves and evaluates NCERT solutions.

  • Extensive coverage of the chapter’s important concepts 

  • Provides curriculum-oriented answers

  • In a basic language that is simple to understand and apply

2. What are the concepts present in Chapter 7 of NCERT Solutions for Class 11 Biology?

Below listed are some of the important concepts covered in Structural Organisation in Animals Class 11:

• • Tissue

  • Animal tissues, which include epithelial tissues, connective tissues, muscle tissues, and neural tissues

  • The neuroglial cell

  • The function of nephridia and the different types of nephridia

  • Peristomium and prostomium

  • Blood cellular components

  • Striated and cardiac muscles

  • Earthworm

  • Simple and compound glands

  • Cockroach

  • Frog

3. Distinguish between simple epithelium as well as compound epithelium.