- 1 Structure and Types of Animal Tissues
- 1.1 Epithelial Tissue: Structure with Diagram, Function, Types
- 1.2 Structure, Functions, and Types of Muscular Tissue
- 1.4 Nervous Tissue – Characteristics, Structure, Function
One of the most fascinating Biology Topics is the study of genetics and how traits are passed down through generations.
Structure and Types of Animal Tissues
Breathing is one of the most vital activities for humans. When we breathe, we can, in fact, feel the movement of our lungs and diaphragm. How do these parts move inside our body? For breathing, we have specialized cells in our bodies, called muscle cells. The contraction and relaxation of these muscle cells result in movement.
During breathing, we inhale oxygen gas (along with air). Where does this oxygen go? It goes to our two lungs and then is transported to all cells of our body through the blood. So, why do cells need oxygen? Mitochondria present in each and every cell of our body utilizes oxygen to generate energy in the form of ATP molecules. These ATP molecules provide energy for all sorts of activities performed by our body cells.
Blood is a fluid connective tissue. It flows and connects different parts of the body. It carries oxygen and food to all cells and in return collects metabolic wastes (e.g., carbon dioxide) from them. Thus, muscles and blood, both are examples of tissues found in our body. On the basis of the functions they perform in the body of multicellular animals, the animal tissues are classified as
- Epithelial tissue
- Muscle or muscular tissue
- Connective tissue
- Nervous tissue
Muscle forms the muscular tissue and blood is a type of connective tissue. These tissues are further differentiated as shown in the following chart:
Epithelial Tissue: Structure with Diagram, Function, Types
Nature: Epithelial tissue is the simplest tissue. It is the protective tissue of the animal body (as the epidermis of plants). The cells of this tissue are tightly packed and they form a continuous sheet. Cells of epithelium contain very little or no intercellular matrix. The tissue covers most organs and cavities within the body. It also forms a barrier to keep different body systems separate. The skin and lining of the buccal cavity, blood vessels, alveoli (of lungs), and kidney tubules are made of epithelial tissue. Epithelial cells lie on a delicate non-cellular basement membrane which contains a special form of matrix protein, called collagen. Epithelial tissue may be simple, i.e., composed of a single layer of cells, or stratified, i.e., made up of several layers of cells.
Functions of Epithelial Tissue:
- The cells of the body surface (i.e., epidermis) form the outer layer of skin.
- These cells protect the underlying cells from drying, injury, and chemical effects.
- They also protect the body from viral or bacterial infection.
- Inside the body, epithelial cells form the lining of the mouth and alimentary canal and protect these organs.
- Epithelial tissues help in the absorption of water and nutrients.
- Epithelial tissues help in the elimination of waste products.
- Some epithelial tissues perform the secretory function. They secrete a variety of substances such as sweat, saliva (mucus), enzymes, etc.
Types of Epithelial Tissue
Depending upon the shape and function of the cells, the epithelial tissues are classified as follows:
- Squamous epithelium
- Cuboidal epithelium
- Columnar epithelium
- Glandular epithelium
- Ciliated epithelium
1. Squamous Epithelium
Nature: Squamous epithelium is made up of thin, flat, irregular-shaped cells which fit together like floor tiles to form a compact tissue. Squamous epithelium is also known as tessellated and pavement epithelium.
Occurrence: It forms the delicate lining of cavities (mouth, oesophagus, nose, pericardium, alveoli, etc.) and of blood vessels and covering of the tongue and skin.
Functions of Squamous Epithelium:
This epithelium protects the underlying parts of the body from mechanical injury, entry of germs, chemicals, and drying. It also forms a selectively permeable surface through which Alteration occurs.
Stratified Keratinized Squamous Epithelium
This is found in the skin and covers the external dry surface of the skin. Cells of this tissue are arranged in many layers. Cells forming different layers of this epithelium are not similar. Deeper layers of the tissue have cuboidal cells which become polygonal and finally flattened (squamous) towards the free surface.
The flattened cells of the superficial layer contain a fibrous protein, keratin, and become dead cells. Florny, scale-like remains of dead squamous cells, ultimately flake away. This epithelium is water-proof and highly resistant to mechanical injury.
2. Cuboidal Epithelium
Nature: It consists of cube-like (cubical) cells that are square in section but the free surface appears hexagonal.
Occurrence: The cuboidal epithelium is found in kidney tubules, thyroid vesicles and in glands (e.g., salivary glands, sweat glands, and exocrine pancreas). It forms the germinal epithelium of gonads (testes and ovaries).
Functions of Cuboidal Epithelium:
It helps in absorption, excretion, and secretion. It also provides mechanical support.
3. Columnar Epithelium
Nature: The columnar epithelium consists of cells that are taller than broader (i.e., pillar-like). The nuclei are towards the base and sometimes the free ends of cells have a brush border containing microvilli.
Occurrence: It forms the lining of the stomach, small intestine, and colon, forming a mucous membrane. It also forms the lining of the gall bladder and oviducts and facilitates movement across the cells.
Functions of Columnar Epithelium:
Its main functions include absorption (e.g., stomach, intestine) and secretion (e.g., mucus by goblet cells or mucous membrane.
Differences between Squamous Epithelium and Columnar Epithelium
|Squamous Epithelium||Columnar Epithelium|
|1. The component cells are thin and flat.||1. The component cells are pillar-like.|
|2. The nucleus lies in the centre of the cell which generally bulged out.||2. The nucleus is located near the base of the cell.|
|3. This tissue occurs in the lung alveoli, blood capillaries, Bowman’s capsule, buccal cavity, skin, etc.||3. It occurs within the layer of the stomach and intestine, their glands, and the covering of the epiglottis.|
|4. It functions as a selectively permeable barrier, in ultrafiltration and wear and tear.||4. It takes part in absorption, secretion, and protective covering.|
4. Glandular Epithelium
The columnar epithelium is often modified to form glands that secrete chemicals.
6. Ciliated Epithelium
Nature: Certain cuboidal or columnar cells have a free border that bears thread-like cytoplasmic outgrowths, called cilia. Such cells form the ciliated epithelium.
Occurrence: Ciliated cuboidal epithelium is found in the sperm ducts. The ciliated columnar epithelium lines the trachea (wind-pipe), bronchi (lungs), kidney tubules, and oviducts (Fallopian tubes).
Functions of Ciliated Epithelium:
The rhythmic, concerted beating of the cilia moves solid particles (e.g., mucus) in one direction through the ducts.
Structure, Functions, and Types of Muscular Tissue
The muscle tissues or muscles of the body form the contractile tissue and are made of muscle cells. Muscle cells are elongated and large-sized, so they are also called muscle fibers. The movements of the body or limbs are brought about by contraction and the relaxation of contractile proteins which are present in muscle cells. The movements of the internal organs such as the heart and alimentary canal, are all caused by muscle tissues. Muscle cells are typically arranged in a parallel arrangement allowing them to work together effectively.
On the basis of their location, structure, and function, there are following three types of muscle fibres:
- Striated muscles
- Smooth muscles
- Cardiac muscles
1. Striated Muscles
Nature: Striated muscles are also known as striped, skeletal or voluntary muscles. Since the entire muscle fibres show alternate dark and light stripes (striations or bands), they are called striped muscles. Since they are attached to the bones and are responsible for body movements, they are called skeletal muscles. And lastly, since these muscles work according to our will, they are also called voluntary muscles.
The striated muscle fibres (cells) are long or elongated, non-tapering, cylindrical, and unbranched. These cells have a number of nuclei (i.e., each muscle cell is multi-nucleated). Each muscle cell is enclosed in a thin but distinct plasma membrane, called sarcolemma. Its nuclei are peripheral in position, i.e., nuclei are located just beneath the sarcolemma. In the sarcoplasm (cytoplasm) of the muscle cell are embedded a large number of contractile elements, called sarcostyles or myofibrils.
Occurrence: Striated muscles occur in the muscles of limbs (e.g., biceps and triceps of arms), body wall, face, neck, etc. Striated muscles present in the tongue, pharynx, diaphragm, and upper part of the esophagus are called visceral striated muscles.
Functions of Striated Muscles:
- Striated muscles are powerful and undergo rapid Contraction. These muscles can get tired and may need rest.
- Striated muscles provide the force for locomotion and all other voluntary movements of the body.
2. Smooth Muscles
Nature: Smooth smooth muscles are also known as unstriated, visceral or involuntary muscles. Smooth muscles occur as bundles or sheets of elongated fusiform or spindle-shaped (pointed at both ends) cells or fibres. These are held together by loose connective tissue. Each muscle cell is enclosed in a plasma membrane. There is a single centrally located cigar-shaped nucleus in the centre of the cytoplasm or sarcoplasm (uninucleate cell). Delicate, contractile threads called myofibrils run longitudinally throughout the cell. These fibrils do not bear any bands, stripes, or striations across the muscle hence, called smooth or unstriated muscles.
Occurrence: Smooth muscles are found in the walls of the hollow (tubular) visceral organs except that of the heart, and so are called visceral muscles. Thus, they occur in the wall of the alimentary canal and internal organs, ducts of glands, urogenital ducts, and blood vessels. Smooth muscles are found in the stomach, intestine, ureter, bronchi, iris of eye, etc.
Functions Smooth Muscles:
- Smooth muscles do not work (contract) according to our will, so they are also called involuntary muscles. The movement of food in the alimentary canal, and opening and closing of tubes are involuntary movements.
- Smooth muscle contracts slowly but can remain contracted for long periods of time. Due to this fact, smooth muscles cause the characteristic peristaltic movements in the tubes. Peristaltic movements are the rhythmic progressive waves of muscular contraction and relaxation. Such wave-like peristaltic movements occur in the gastrointestinal tract and male genital tract.
- In some organs, smooth muscles contract throughout the organ to produce extrusive movements as in the urinary bladder, the gall bladder, and the uterus.
3. Cardiac Muscles
Nature: Cardiac muscles show characteristics of both smooth and striated muscles. Cardiac muscles are composed of branched fibres and the branches join to form a network. Each fibre or cell is surrounded by sarcolemma, a cytoplasm (sarcoplasm) with longitudinal myofibrils, and a centrally located nucleus (i.e., each cell is uninucleated). The intercellular spaces of cardiac muscles are filled with abundant loose connective tissue supplied with blood capillaries.
Cardiac muscles have stripes of light and dark bands. In addition, these muscle fibers show densely stained cross-bands called intercalated impulses (Act as impulse boosters). These are regions of interdigitations of plasma membranes (sarcolemmas) consisting of adjacent muscle cells or fibres (i.e., each fibre of cardiac muscle is formed due to the joining of an individual uninucleate muscle cell to one another in a linear arrangement).
Occurrence: The cardiac muscles occur in the heart (i.e., in the walls of the heart).
Functions of Cardiac muscles:
- Cardiac muscles contract and relax rapidly, rhythmically, and tirelessly throughout a lifetime. They contract endlessly from the early embryonic stage until death.
- The contraction and relaxation of the heart muscles help to pump and distribute blood to various parts of the body.
Comparison of Smooth, Skeletal, and Cardiac Muscles
|Smooth muscle||Skeletal muscle||Cardiac muscle|
|1. Not striated||Striated||Striated|
|3. Not branched||Not branched||Branched|
|5. No discs||No discs||Intercalated discs|
|8. Contraction not inherent||Contraction not inherent||Contraction inherent|
Connective Tissue – Definition, Components, & Functions
The connective tissue is specialized to connect and anchor various body organs. The tissues can connect bones to each other, muscles to bones, bind tissues, and can also give support to various parts of the body by creating a packing around organs. The packing would prevent the organs from getting displaced by body movements. Thus, the main functions of connective tissue are binding, supporting, and packing together different organs of the body.
The cells of connective tissue are living, separated from each other (i.e., loosely spaced), and low in number. The homogeneous, gel-like intercellular substance called medium or matrix forms the main bulk of the connective tissue. Thus, the space between cells is filled with a non-living matrix which may be solid as in bone and cartilage and fluid as in the blood. Matrix is fibrous in nature and binds other tissues. In fact, the nature of the matrix decides the function of connective tissue.
Cells of Connective Tissue
Connective tissue contains the following types of cells:
- Fibroblasts: They form ground substances and fibres (e.g., collagen).
- Adipose cells: They store fats (lipids) in their vacuoles.
- Macrophages: These may be free-moving or fixed phagocytes (leucocytes or WBCs). They are involved in the destruction and removal of invading bacteria, foreign bodies and damaged cells from tissues.
- Mast cells: They secrete substances such as heparin (anticoagulant), histamine (vasodilator), and serotonin (vaso-constrictor). They promote inflammation of the infected area.
- Immunocytes: These include cells such as lymphocytes and plasma cells both producing antibodies for the immune response.
Protein fibres of the matrix
The matrix of connective tissue is secreted by the component cells. It chemically contains GAGs (i.e., glycosaminoglycans or mucopolysaccharides). The matrix also contains the following three main types of protein fibres:
- White fibres of collagen
- Yellow fibres of elastin
- Reticular fibres of reticulin
Types of Connective Tissue
In animals, there are following five types of connective tissues:
- Areolar (or loose) connective tissue
- Dense regular connective tissue
- Adipose tissue
- Skeletal tissue;
- Fluid connective tissue
1. Areolar or Loose Connective Tissue
Nature: As the name suggests, this tissue is a loose and cellular connective tissue. Its matrix consists of two kinds of fibres: 1. White collagen fibres (which change into gelatin on boiling in water) and 2. Yellow elastic fibres or elastin. Also scattered in the matrix are several kinds of irregular cells (e.g., fibroblasts), some of which can engulf bacteria and prevent infection (e.g., macrophages).
Occurrence: It is the simplest and most widely distributed connective tissue. It joins skin to muscles, fills spaces inside organs, and is found around muscles, blood vessels, and nerves.
Areolar Connective Tissues:
- It acts as a supporting and packing tissue between organs lying in the body cavity. The Matrix of this tissue is important in the diffusion of oxygen and nutrients from small blood vessels.
- It helps in the repair of tissues after an injury.
- It also helps in combating foreign toxins.
- It fixes skin to underlying muscles.
2. Dense Regular Connective Tissue
It is a fibrous connective tissue. It is characterized by an ordered and densely packed collection of fibres and cells. Dense regular connective tissue is the principal component of tendons and ligaments and aponeuroses.
Tendons: Tendons are cord-like, strong, inelastic, structures that join skeletal muscles to bones. A tendon is a white fibrous tissue that has great strength but limited flexibility. It consists of parallel bundles of collagen fibres, between which are present, rows of fibroblasts (called tendinocytes). Collagen fibres are bounded by areolar connecting tissue.
Ligaments: They are elastic structures that connect bones to bones. A ligament is highly elastic and has great strength but contains very little matrix. In the ligament, some elastic and many collagen fibres are bound together by areolar connective tissue. Fibroblasts are compressed in between regular rows of fibres.
Ligaments strengthen the joint and permit normal movement but prevent over-flexing or over-extension. A sprain is caused by excessive pulling (stretching) of ligaments.
Differences between Tendon and Ligament
|1. Inelastic||1. Elastic|
|2. Join muscles to bone.||2. Connect bones to bones.|
|3. Made up of white fibres.||3. Made up of white as well as yellow fibres.|
Aponeuroses: These are broad sheets of dense, fibrous, collagenous connective tissues that cover, invest and form the terminations and attachments of various muscles.
3. Adipose Tissue
Nature: Adipose tissue is basically an aggregation of fat cells or adipocytes. Each fat cell is rounded or oval in shape and contains a large droplet of fat that almost fills it. The fat cells are arranged into lobules separated by partitions of collagen and elastin fibres. These partitions carry blood vessels of lobules.
Occurrence: The adipose tissue is abundant below the skin, between the internal organs (e.g., around the kidneys) and in the yellow bone marrow.
Functions of Adipose Tissue:
- Serves as a fat reservoir.
- Provides shape to the limbs and the body.
- Keeps visceral organs in position. It forms shock-absorbing cushions around the kidneys and eyeballs.
- Acts as an insulator. Being a poor conductor of heat, it reduces heat loss from the body, i.e., it regulates body temperature.
4. Skeletal Tissue
The skeletal or supporting tissue includes cartilage and bone which form the endoskeleton of a vertebrate body.
Nature: The cartilage is a specialized connective tissue that is compact and less vascular. It has widely spaced out cells. Its extensive matrix is composed of proteins and is slightly hardened by calcium salts. Its matrix is produced and maintained by the chondrocytes. Matrix is solid, cheese-like, and firm but also slightly elastic. This accounts for its flexible nature.
The matrix of cartilage has a delicate network of collagen fibres and living cells, chondrocytes. Chondrocytes are present in fluid-filled spaces known as lacunae. Blood vessels are absent in the matrix. Chondrocytes multiply by mitosis and help in the internal growth of cartilage. Thus, cartilage is capable of continuous and rapid growth.
Occurrence: Cartilage is located in the following body parts: ear pinna, nose tip, epiglottis, intervertebral discs, end of long bones, lower ends of ribs, and rings of the trachea (wind-pipe).
Functions of Cartilage:
It provides support and flexibility to the body parts. It smoothens the surface at joints.
Nature: Bone is a very strong and non-flexible tissue. Like cartilage, bone is a specialized connective tissue. It is porous, highly vascular, mineralized, hard and rigid. Its matrix is made up of proteins (e.g., osteonectin, osteocalcin, proteoglycan, and collagen). The matrix of bone is rich in salts of calcium and magnesium such as phosphates and carbonates of calcium and magnesium (e.g., hydroxyapatite). These minerals are responsible for the hardness of the bone. The matrix of bone is in the form of thin concentric rings, called lamellae.
Bone cells, called osteoblasts or osteocytes, are present between the lamellae in fluid-filled spaces called lacunae. All lacunae of the bone communicate with each other by a network of fine canals, called canaliculi. Each canaliculus is filled with a delicate cytoplasmic process of the bone cell. Through canaliculi, each bone cell of each lacuna receives food and oxygen and eliminates waste.
Functions of Bone:
Bone forms the endoskeleton in human beings and other vertebrates except for sharks. It serves the following functions:
- Provides shape to the body.
- Provides skeletal support to the body.
- Protects vital body organs such as the brain, lungs, etc.
- Serves as a storage site for calcium and phosphate.
- Anchors the muscles.
Differences between Bone and Cartilage
|1. Hard and inflexible||1. Flexible|
|2. Porous||2. Non-porous|
|3. Blood vessels present||3. Blood vessels absent|
|4. Matrix made up of protein and mineral salts (e.g. calcium phosphate).||4. Matrix made up of protein.|
5. Fluid Connective Tissue
Fluid connective tissue links the different parts of the body and maintains continuity in the body. It includes blood and lymph.
Blood is a fluid connective tissue. In this tissue, cells (or corpuscles) move in a fluid or liquid matrix or a medium called blood plasma. Blood plasma does not contain protein fibres but contains cells called blood corpuscles or blood cells. These blood corpuscles or cells are:
- Red Blood Corpuscles (RBCs) or Erythrocytes
- White Blood Cells (WBCs) or Leucocytes
RBCs and WBCs are living, while plasma and platelets are non-living. Plasma forms 55 percent of the total volume of blood. It is a complex fluid and contains inorganic salts and organic compounds. Organic substances of plasma are soluble proteins such as albumins (maintain osmotic pressure of blood), globulins (some act as antibodies), fibrinogen (used in blood clotting); and glucose, amino acids, lipids, vitamins, enzymes, hormones, and waste materials (urea, uric acid).
Red blood corpuscles (RBCs) are large in number and have iron-containing red respiratory pigment, the haemoglobin. The erythrocytes of most vertebrates are oval-shaped, nucleated, and biconvex. However, erythrocytes of mammals are circular, biconcave, disc-like, and lack nuclei. In this way, mammalian erythrocytes have an increased surface area for gaseous exchange and they accommodate much more haemoglobin in them than RBCs of other animals. Erythrocytes play a vital role in the transport of oxygen.
White blood cells (WBCs) are of two main kinds: phagocytes and immunocytes. Phagocytes are capable of phagocytosis and they carry out the function of body defence by engulfing bacteria and other foreign substances.
Phagocytes are of two types: 1. Granulocytes which have irregular-shaped nuclei and cytoplasmic granules with specific staining properties. They include neutrophils, basophils, and eosinophils. 2. Agranular leucocytes have no cytoplasmic granules and include monocytes. Monocytes have a large nucleus indented on one side and a large amount of cytoplasm. They ultimately migrate to body tissues and transform into macrophages and histiocytes. Immunocytes produce antibodies and are involved in the immune response. They include lymphocytes which have a nearly spherical nucleus and little cytoplasm with no granules. Some lymphocytes later on transform into plasma cells.
Blood platelets are minute, anucleated, fragile fragments of giant bone marrow cells, called megakaryocytes.
Formed Elements of Blood
|Formed Element||Number or Percentage|
|1. Erythrocytes (Red blood corpuscles)||4-6 million/mm3|
|2. Leucocytes (White blood cells)||6000-9000/mm3|
|(ii) Monocytes||3 – 7%|
|(i) Neutrophils||55 – 60%|
|(ii) Eosinophils||2 – 5%|
|(iii) Basophils||0 – 1%|
|3. Platelets||200,000 – 400,000/mm3|
*Percentage of white blood cells.
Difference between Red Blood Corpuscles (Erythrocytes) and White Blood Cells (Leucocytes)
|Red Blood Corpuscles (RBCs)||White Blood Cells (WBCs)|
|1. They are red in colour.||1. They are colourless.|
|2. Size of each RBC is about 7.2 micrometers.||2. Size of WBCs varies between 10 to 20 micrometers.|
|3. Their number is 4 to 6 million/mm3.||3. Their number is 6000-9000/mm3.|
|4. They are biconcave rounded in shape.||4. The shape of WBCs is rounded to amoeboid.|
|5. Nucleus is absent. (That is why they are called corpuscles).||5. Nucleus is present.|
|6. The cells contain haemoglobin.||6. The cells do not contain haemoglobin.|
|7. Most of the cell organelles are absent in these cells.||7. Cell organelles are present in these cells.|
|8. They are of only one type.||8. They are of five types.|
|9. Life span of each RBC is 120 days.||9. Life span of each WBC is generally shorter (a few hours to four days).|
|10. They transport oxygen and to some extent carbon.||10. They function in defence and immunity.|
Occurrence: Blood occurs in blood vessels called arteries, veins, and capillaries which are connected together to form the circulatory system. The extensive branching network of vessels enables blood to reach every part of the body.
Functions of Blood:
- Blood transports nutrients, hormones, and vitamins to the tissues and transports excretory products from the tissues to the liver and kidney.
- The red blood corpuscles (RBCs) carry oxygen to the tissues for the oxidation of foodstuff.
- The white blood cells (WBCs) fight disease either by engulfing and destroying foreign bodies or by producing antitoxins and antibodies that neutralize the harmful effects of germs.
- Blood platelets disintegrate at the site of injury and help in the clotting of blood.
Nature: Lymph is a colorless fluid that is filtered out of the blood capillaries. Since it is a part of blood, its composition is similar to that of blood except that red blood corpuscles and some blood proteins are absent in it. In the lymph, white blood cells are found in abundance.
Functions of Lymph:
- Lymph transports the nutrients (oxygen, glucose) that may have been filtered out of the blood capillaries back into the heart to be recirculated in the body.
- It brings CO2 and nitrogenous wastes from tissue fluid to blood.
- Being loaded with WBCs such as lymphocytes, the lymph protects the body against infection. It forms the defence or immune system of the body.
Nervous Tissue – Characteristics, Structure, Function
Nature: Nervous tissue is a tissue that is specialized to transmit messages within our body. The brain, spinal cord, and nerves are all composed of nervous tissue. Nervous tissue contains highly specialized unit cells called nerve cells or neurons. Neurons have the ability to receive stimuli from within or outside the body and to conduct (send) impulses (signals) to different parts of the body. The impulse travels from one neuron to another neuron.
Each neuron has the following three parts:
- The cyton or cell body contains a central nucleus and cytoplasm with characteristic deeply stained particles, called Nissl’s granules (i.e., clumps of ribosomes).
- The dendrons are short processes arising from the cyton and further branching into dendrites; and
- The axon is a single, long cylindrical process of uniform diameter. It forms fine branches terminally.
Each such twig-like branch of the axon ends in a swollen structure, called a synaptic knob or bouton. Bouton contains acetylcholine-filled vesicles. Acetylcholine (ACh) is an important neurotransmitter (i.e., a substance that plays an important role in the transmission of nerve impulses within the nervous system). Axon is also called nerve fibre.
Functions of Nervous Tissue:
The dendrites receive impulses and the axon takes impulses away from the cell body.
Difference between Axon and Dendrite
|1. It is a long uniformly thickened fiber-like process of a neuron.||1. It is a short tapering process of a neuron.|
|2. It is always covered with a sheath (e.g., medullary sheath).||2. A sheath is absent.|
|3. Nissl’s granules are absent. Neurofibrils are, however, present.||3. Both Nissl’s granules and neurofibrils are present.|
|4. It carries impulses away from the cell body.||4. It carries impulses towards the cell body.|
What are the types of animal tissue and their functions? ›
|Connective Tissue Proper||Provides support and protection to the body|
|Vascular Tissue||Transport of materials in the body|
|Skeletal Tissue||It supports the body and gives it proper shape and form|
Permanent tissues and meristematic tissues are the two types of tissues found in plants. Animal tissues, on the other hand, are divided into four categories: muscular tissue, epithelial tissue, connective tissue, and nerve tissue. Meristematic tissues in plants assist them in growth throughout their lives.What are examples of tissues in the animal body? ›
- Adipose Tissue.
Animal tissues are tissues which are animal body is made of. There are four types of tissues found in animals: epithelial tissue, connective tissue, muscle tissue, and nervous tissue.What are the functions of the 4 types of tissues? ›
Epithelial tissues act as coverings controlling the movement of materials across the surface. Connective tissue integrates the various parts of the body and provides support and protection to organs. Muscle tissue allows the body to move. Nervous tissues propagate information.What is the function of the connective tissue in animals? ›
Connective tissues have been regarded as a supporting tissue because they connect and keep together many organs of the body, they provide mechanical support to different parts of the body and to the whole body as well, and protect and isolate many organs.What are the examples of plant and animal tissue? ›
Examples of plant tissues include: xylem, phloem, parenchyma, collenchyma, sclerenchyma, epidermis and meristematic tissue. Examples of animal tissues are: epithelial tissue, connective tissue, muscle tissue and nerve tissue.What are examples of tissues in plants and their functions? ›
Dermal tissue covers and protects the plant. The ground tissue serves as a site for photosynthesis, provides a supporting matrix for the vascular tissue, and helps to store water and sugars. The vascular tissue transports water, minerals, and sugars to different parts of the plant.How will you classify the different cell types of plant animal tissues and its functions? ›
Plant tissues include xylem, phloem, collenchyma, sclerenchyma, epidermis and meristematic tissue. Animal tissues include epithelial tissue, connective tissue, muscle tissue and nerve tissue. Plant and animal tissues are used in traditional technology, medical technology and cloning processes.What is the function of the connective tissue? ›
Tissue that supports, protects, and gives structure to other tissues and organs in the body. Connective tissue also stores fat, helps move nutrients and other substances between tissues and organs, and helps repair damaged tissue.
What are 3 examples of cells found in animal tissue? ›
The tissues of multicellular, complex animals are four primary types: epithelial, connective, muscle, and nervous.What are the animal tissues summary? ›
Animal tissues are made up of animal cells that have been grouped together. The structure, function, and origin of these tissues are all different. Epithelial, connective, muscular, and nervous tissues are the four types of tissues found in animals.Why are animal tissues important? ›
In addition, animals possess unique tissues, absent in fungi and plants, which allow coordination (nerve tissue) of motility (muscle tissue). Animals are also characterized by specialized connective tissues that provide structural support for cells and organs.What are examples of plant tissues? ›
Different plant tissues: (1) pith, (2) protoxylem, (3) xylem, (4) phloem, (5) sclerenchyma, (6) cortex, and (7) epidermis.What is the function of muscle tissue? ›
Muscle tissue is composed of cells that have the special ability to shorten or contract in order to produce movement of the body parts.What are examples of cells? ›
- Stem cells. Stem cells are cells that must choose what they are going to become. ...
- Bone cells.
- Blood cells. There are many types of blood cells, including:
- Muscle cells. Also called myocytes, muscle cells are long, tubular cells. ...
- Sperm cells. ...
- Female egg cell. ...
- Fat cells. ...
- Nerve cells.
Nervous tissue is found in the brain, spinal cord, and nerves. It is responsible for coordinating and controlling many body activities. It stimulates muscle contraction, creates an awareness of the environment, and plays a major role in emotions, memory, and reasoning.What is an example of connective tissue in animals? ›
Bone, blood, fat, and cartilage are all connective tissues. Connective tissue can be densely packed together, as bone cells are, or loosely packed, as adipose tissue (fat cells) are.What is epithelial animal tissue? ›
The covering or protective tissues in the animal body are epithelial tissues. Epithelium covers most organs and cavities within the body. It also forms a barrier to keeping different body systems separate.What is areolar tissue function? ›
The areolar connective tissue is a type of connective tissue that is present throughout the human body. It provides support and helps to protect organs, muscles, and many other tissues. It also helps to bind the skin together. Provides a protective framework that keeps major structures in place and offers support.
What is an example of a tissue? ›
When a group of cells come together and perform same function in a harmony is called a tissue. Eg: Blood is a fluid connective tissue and bones are also connective tissues.What is the structure and function of animal cell and how it is different from plant cell? ›
Animal Cells versus Plant Cells
Animal cells each have a centrosome and lysosomes, whereas plant cells do not. Plant cells have a cell wall, chloroplasts and other specialized plastids, and a large central vacuole, whereas animal cells do not.
Plant tissue specializes in cellulose, which is a sturdy substance that plays an important role in plant life. Animal tissue specializes in protein, which plays an essential part in animal life. Plant tissue mainly consists of sugar molecules known as cellulose.What are the 3 differences between plant cells and animal cells explain each of their functions? ›
Three differences between a plant cell and an animal cell are: Animal cell lack cell wall, unlike a plant cell which has a cellulosic cell wall. Animal cell lack chloroplast, whereas plant cell has chloroplast. Animal cell has centrioles, centrosome, and lysosome but plant cell lack them.What is an example of an epithelial tissue? ›
Some examples of epithelial tissue include: The outer layer of your skin (epidermis). The lining of your intestines. The lining of your respiratory tract.What is the skeletal connective tissue? ›
The skeletal tissue is a connective tissue that possesses a solid matrix and the living cells in the fluid-filled spaces called lacunae. Generally, the skeletal tissues provide support and protection, thereby forming an endoskeleton. There are two types of skeletal tissues, namely, Bones and Cartilages.Which is an example of connective tissue proper? ›
Connective tissue proper includes: loose connective tissue (also called areolar) and dense (irregular) connective tissue. Specialized connective tissue types include: dense regular connective tissue, cartilage, bone, adipose tissue, blood, and hematopoietic tissue.What are 5 examples of animal cells? ›
Examples of common animal cell types include skin cells, muscle cells, blood cells, fat cells, nerve cells, sex cells, and stem cells.What type of tissue provides protection and helps reduce water loss in plants? ›
Dermal tissue covers and protects the plant, and controls gas exchange and water absorption (in roots). Dermal tissue of the stems and leaves is covered by a waxy cuticle that prevents evaporative water loss.What are three examples for cells of connective tissue? ›
Specialized connective tissues are diverse as they are composed of varying specialized cells and ground substance. Specialized connective tissues include adipose, cartilage, bone, blood, and reticular tissues.
How many animal tissues are there? ›
A tissue is a group of cells connected to each other that collectively perform similar functions in an organism. All contents of the body including structures and various organs are made of tissues. The animal body comprises four basic types of tissues, all of which vary in their origin and function.What are the 7 tissues of the body? ›
In common terms, the seven types of Dhatus are plasma, blood, muscle, fat, bone, bone marrow and reproductive fluid. In Ayurveda, they are called Sapta Dhatus - Rasa, Rakta, Mamsa, Meda, Asthi, Majja and Sukhra respectively.What type of tissue is bone? ›
Bone is made up of compact tissue (the hard, outer layer) and cancellous tissue (the spongy, inner layer that contains red marrow).What is an example of animal tissue quizlet? ›
There are several main types of animal tissue including:epithelial,muscle,nervous tissue and connective tissues such as bone, cartilage,blood and loose connective tissue(sometimes called areolar tissue).What are examples of animal organs? ›
The stomach, liver, lungs, and heart are examples of organs found in animals. Stems and leaves are two types of organs found in plants. In higher organisms, organs are grouped into organ systems.What are true tissues in animals? ›
true tissue (noun, pl. true tissues; synonym: parenchyma) – isodiametric cells joined together in three dimensions, always originating from organized meristematic growth of a single cell that is capable to divide into several, isodiametric planes, thus giving off new cells into several directions.What are the three functions of roots? ›
They have three major jobs: absorbing water and minerals, anchoring and supporting the plant, and storing food. Absorbing water and minerals: Thin-walled epidermal cells and root hairs are well suited to absorb water and dissolved minerals from the soil.What is the function of the xylem and phloem? ›
The xylem distributes water and dissolved minerals upward through the plant, from the roots to the leaves. The phloem carries food downward from the leaves to the roots. Xylem cells constitute the major part of a mature woody stem or root.What is tissue system? ›
Tissue is a biological organizing level in biology that lies between cells and an entire organ. Various tissues are functionally grouped together to form organs. The epidermis, ground tissue, and vascular tissue are the three major tissue systems used to classify tissues in plant anatomy.Do all animals have 4 types of tissue? ›
A tissue is a group of connected cells that have a similar function within an organism. There are four basic types of tissue in the body of all animals, including the human body.
What is the function of connective tissue? ›
Tissue that supports, protects, and gives structure to other tissues and organs in the body. Connective tissue also stores fat, helps move nutrients and other substances between tissues and organs, and helps repair damaged tissue.What is epithelial tissue and its function? ›
What is the epithelium? The epithelium is a type of body tissue that forms the covering on all internal and external surfaces of your body, lines body cavities and hollow organs and is the major tissue in glands.What are the different types of connective tissue in animals? ›
There are mainly four kinds of connective tissues that are found in animal bodies. Those are the adipose connective tissues, the dense irregular tissues, the dense regular tissues, the areolar connective tissues. Bones, cartilages, and blood are also regarded as connective tissues.What are the different types of tissue in animal cells? ›
The tissues of multicellular, complex animals are four primary types: epithelial, connective, muscle, and nervous. Recall that tissues are groups of similar cells group of similar cells carrying out related functions.What is an example of an animal epithelial tissue? ›
The squamous epithelial cells line the cavities of the mouth, oesophagus, alveoli, blood vessels and air sacs of lungs. Cuboidal Epithelium – These cells are cuboidal in shape. They are found in the salivary glands, tubular parts of nephrons in kidneys, sweat glands etc.Why animals have different types of tissues? ›
Plant and animal tissues are different because plants tend to grow throughout their life, whereas animals grow up to a certain period. Moreover, plants do not show locomotion but animals show locomotion, which necessitates the presence of different types of tissues.What is the function of the fibrous tissue? ›
Fibrous connective tissue supports, protects, and holds bones, muscles, and other tissues and organs in place. Ligaments, tendons, the inner layer of the skin, and the sclera (the white outer layer of the eye) are all types of fibrous connective tissue. Also called dense connective tissue.What is the function of the nervous tissue? ›
Nervous tissue is found in the brain, spinal cord, and nerves. It is responsible for coordinating and controlling many body activities. It stimulates muscle contraction, creates an awareness of the environment, and plays a major role in emotions, memory, and reasoning.What is an example of a connective tissue? ›
Specialized connective tissue encompasses a number of different tissues with specialized cells and unique ground substances. Some are solid and strong, while others are fluid and flexible. Examples include adipose, cartilage, bone, blood, and lymph.What are the 3 connective tissues? ›
The collagen and elastic fibers of connective tissue proper are histologically distinguishable as three fiber types: collagen, reticular, and elastic fibers.
What kind of tissue is blood? ›
Blood is one of the connective tissues. As a connective tissue, it consists of cells and cell fragments (formed elements) suspended in an intercellular matrix (plasma).What is the adipose tissue in animals? ›
Adipose tissue is not only a tissue where energy is stored but is also involved in regulating several body functions such as appetite and energy expenditure via its endocrine activity. Moreover, it thereby modulates complex processes like reproduction, inflammation and immune response.What is muscle tissue in animals? ›
Muscle tissue is a specialized tissue found in animals which functions by contracting, thereby applying forces to different parts of the body. Muscle tissue consists of fibers of muscle cells connected together in sheets and fibers.What is dense connective tissue in animals? ›
There are two main forms of dense connective tissues: dense regular connective tissue – found in tendons and ligaments. dense irregular connective tissue – found in lower layers of the skin (dermis) and in the protective white layer of the eyeball.