Simple permanent tissues are composed of cells which are structurally and functionally similar. They are of three types – parenchyma, collenchyma and sclerenchyma.

1. Parenchyma –

Parenchyma tissue consists of relatively unspecialised cells with thin cell walls. They are live cells. They are usually loosely packed, so that large spaces between them.  This tissue provides support to plants and also stores food. In some cases, it contains chlorophyll and performs photosynthesis, and then it is called as chlorenchyma. In aquatic plants, large air cavities are present in parenchyma to give buoyancy to the plants to help them float. Such a parenchyma type is called aerenchyma. The parenchyma of stems and roots also stores nutrients and water.

ii. Collenchyma –

The cells of collenchyma tissue are living, elongated and irregularly thickened at the corners. There is very little or no intercellular space. It allows easy bending in various parts of a plant (leaf, stem) without breaking. Thus, provides flexibility to the plant. It also provides mechanical support to plants.  

iii. Sclerenchyma –

The cells of sclerenchyma tissue are dead. They are long and narrow as the walls are thickened due to deposition of lignin. The walls of cells are so thick that there is no internal space inside the cell. This tissue is present in stems, around vascular bundles, in the veins of leaves and in the hard covering of seeds and nuts. It provides strength to the plant parts and makes the plant hard and stiff.

• Meristematic Tissue:

Meristematic tissues are growth tissues and found in the growing regions of the plant. According to their position in plant, meristems are apical, lateral and intercalary.

1. Apical meristem - Apical meristem is present at the growing tips of stems and roots and increases the length of the stem and the root.
2. Lateral meristem – Lateral meristems are found beneath the bark. The girth of the stem or root increases due to lateral meristem (cambium).
3. Intercalary meristem - Intercalary meristem is the meristem at the base of the leaves or internodes (on either side of the node) on twigs. It increases the length of the organs such as leaves and internodes.

Characteristics of Meristematic Tissues:

1. Their cells are similar in structure and have thin cellulose cell walls.
2. The cells are active and have dense cytoplasm.
3. They contain few vacuoles or no vacuoles at all.
4. The meristematic cells are compactly arranged and do not contain any intercellular space between them.

Complex permanent tissues –

Complex tissues are made of more than one type of cells. All these cells coordinate to perform a common function. Xylem and phloem are examples of such complex tissues. They are both conducting tissues and constitute a vascular bundle.

1. Xylem –

Xylem is a vascular and mechanical tissue. It consists of tracheids, vessels, xylem parenchyma and xylem fibres. Except xylem parenchyma, all xylem elements are dead and bounded by thick lignified walls. Tracheids and vessels are tubular structures which transports water and minerals vertically. The parenchyma stores food and helps in the sideways conduction of water. Fibres are mainly supportive in function.

ii. Phloem –

Phloem contains tubes but performs no mechanical function. Phloem is made up of four types of elements: sieve tubes, companion cells, phloem fibres and the phloem parenchyma. Sieve tubes are tubular cells with perforated walls. Phloem is unlike xylem in that materials can move in both directions in it. Phloem transports food from leaves to other parts of the plant. Except for phloem fibres, phloem cells are living cells.

Characteristics of Solanaceae Family

The following are the characteristic features of the Solanaceae family:

Vegetative Characters

• Root System: Taproot system.
• Stem: Erect or climber; Solanaceae includes herbs, shrubs, small trees, and climbers.
• Leaves:  Alternate, simple or pinnately compound (rarely); exstipulate; reticulate venation.

Floral characters

• Inflorescence: Racemose- terminal or axillary raceme; Cymose- solitary in Solanum.
• Flower: Complete, bisexual, actinomorphic, hypogynous.
• Calyx: Five sepals, gamosepalous; valvate aestivation.
• Corolla: Five petals, gamopetalous, valvate aestivation.
• Androecium: Five stamens, epipetalous; anthers basifixed.
• Gynoecium: Syncarpous, bicarpellary, bilocular, superior ovary, axile placentation.
• Fruit: Berry/ capsule.
• Seed: Numerous, endospermous

Characteristics of Liliaceae Family

The following are the important characteristics of the Liliaceae family.

Vegetative Characters

• Root: Fibrous root system.
• Stem: Erect; Liliaceae includes perennial herbs which propagate through bulbs or rhizomes.
• Leaves:  Alternate, simple; exstipulate; parallel venation.

Floral characters

• Inflorescence: Cymose- solitary; umbellate clusters.
• Flower: Complete, bisexual, actinomorphic; hypogynous, perianth present.
• Perianth: Indistinctive sepal and petal; six tepals (3+3), often united tepals; valvate aestivation.
• Androecium: Six stamens in two whorls (3+3).
• Gynoecium: Syncarpous, tricarpellary, trilocular, superior ovary with axile placentation.
• Fruit: Mostly Capsule and sometimes berry.
• Seed: Endospermic seeds.

• The arrangement of ovules within the ovary is known as placentation.
• The placentation is of different types namely, marginal, axile, parietal, basal, central and free central.
• In marginal placentation the placenta forms a ridge along the ventral suture of the ovary and the ovules are borne on this ridge forming two rows. Example- pea
• When the placenta is axial and the ovules are attached to it in a multilocular ovary, the placentaion is said to be axile. Example- china rose.
• In parietal placentation, the ovules develop on the inner wall of the ovary or on peripheral part and ovary become twochambered due to the formation of the false septum. Example- mustard
• In free central, the ovules are borne on central axis and septa are absent. Example- Dianthus
• In basal placentation, the placenta develops at the base of ovary and a single ovule is attached to it. Example – sunflower.

• The plant is described beginning with its habit, vegetative characters such as roots, stem and leaves and then floral characters inflorescence and flower parts.
• After describing various parts of plant, a floral diagram and a floral formula are presented, which is represented by some symbols.
• In the floral formula, Br stands for bracteate K stands for calyx , C for corolla, P for perianth, A for androecium and G for Gynoecium, G for superior ovary and G for inferior ovary, for male, for female , ⊕ for actinomorphic and for zygomorphic nature of flower.
• Fusion is indicated by enclosing the figure within bracket and adhesion by a line drawn above the symbols of the floral parts.
• A floral diagram provides information about the number of parts of a flower, their arrangement and the relation they have with one another.
• The position of the mother axis with respect to the flower is represented by a dot on the top of the floral diagram.
• Calyx, corolla, androecium and gynoecium are drawn in successive whorls, calyx being the outermost and the gynoecium being in the centre.
• Floral formula also shows cohesion and adhesion within parts of whorls and in between whorls.

Taxonomical aids are the collections of samples or preserved organisms which help in extensive research for the identification of various taxonomic hierarchy. Classifying organisms into various categories needs a lot of field and laboratory study. This is an essential process, because taxonomic categorization helps in identifying many organisms necessary in various fields like agriculture, industries, bio resources, etc.

The stomach has four parts :

(1) Cardiac stomach : It is proximal part. The opening of oesophagus into cardiac stomach is guarded by cardiac sphincter which prevents the regurgitation of food. 

Section of the stomach

(2) Fundus : It extends above cardiac aperture and is filled with air. The part of cardiac stomach which extends towards anterior end above level of cardiac aperture is called fundus.

(3) Body : It is the middle large part of the stomach.

(4) Pyloric stomach : It is the distal narrowest part of stomach which opens into duodenum. Its opening is guarded by pyloric sphincter which permits the passage of fine-food particles into duodenum.

• Vegetative characters
• Plants mostly, herbs, shrubs and small trees Stem: herbaceous rarely woody, aerial; erect, cylindrical, branched, solid or hollow, hairy or glabrous, underground stem in potato
• Leaves: alternate, simple, rarely pinnately compound, exstipulate; venation reticulate

In two kingdom classification, there was no differentiation between the eukaryotes and prokaryotes, unicellular and multicellular and photosynthetic and non-photosynthetic organisms. In the two-kingdom classification the bacteria, blue-green algae, fungi, mosses all were included under the kingdom Plantae. It placed together groups which widely differed from each other. A large number of organisms did not fall into any category. Thus, the two-kingdom classification was insufficient and inadequate.

The five kingdom classification resolved the issues as it considered other factors like cell structure, mode of nutrition, thallus organisation, reproduction and phylogenetic relationships. This system of classification placed the organisms into five different categories. All the prokaryotes were placed under Kingdom Monera. The unicellular eukaryotes were placed under Kingdom Protista. The fungi occupied a separate kingdom. Thus, it proved to be adequate and much better than the two-Kingdom classification. 

Under suitable condition, slime moulds form plasmodium.

Binomial Nomenclature “Binomial nomenclature is the biological system of naming the organisms in which the name is composed of two terms, where, the first term indicates the genus and the second term indicates the species of the organism.”

Red, green, and brown algae have different types of pigments which give them their color. (Brown algae gets its color from the xanthophylls pigment fucoxanthin, red algae get their color from phycoerythrin, green is from chlorophyll.) These pigments have a certain chemical structure that allows them to absorb light. Phaeophyta (brown algae) A division of algae which includes no single-celled species; almost all are marine, growing mostly in the intertidal regions (but species of Bodenella and Heribaudiella occur in fresh water). They are the dominant seaweeds in the colder waters of the northern hemisphere.

Asexual reproduction in fungi:

1. fission of somatic cell
2. Budding of somatic cell
3. Fragmentation or disjoining of hyphae
4. Asexual spore formation

The cone bearing plants are called Conifers.

Features such as arrangement of cells, body symmetry, nature of coelom, patterns of digestive, circulatory or reproductive systems are the basis of animal classification.

Bryophytes are an informal group consisting of three divisions of non-vascular land plants (embryophytes): the liverworts, hornworts and mosses. They are characteristically limited in size and prefer moist habitats although they can survive in drier environments. The bryophytes consist of about 20,000 plant species. The aim is to give you a good understanding of bryophyte structure and of the similarities and differences between the three groups.

The seedless vascular plants include club mosses, which are the most primitive; whisk ferns, which lost leaves and roots by reductive evolution; and horsetails and ferns. Ferns are the most advanced group of seedless vascular plants. They are distinguished by large leaves called fronds and small sporangia-containing structures called sori, which are found on the underside of the fronds.

The pyrenoid, a dense structure inside or beside chloroplasts of certain algae, consists largely of ribulose biphosphate carboxylase, one of the enzymes necessary in photosynthesis for carbon fixation and thus sugar formation. Starch, a storage form of glucose, is often found around pyrenoids.