Science (Plant Kingdom) - CTET & State TET MCQ

A cell wall is a rigid layer of polysaccharides lying outside the plasma membrane of the cells of plants, fungi, and bacteria.

• In the algae and higher plants, it consists mainly of cellulose.

Plant cell wall:

• It provides a structural framework to support the growth of plants.
• The cell wall also acts as the first line of defence against pathogens.
• A plant cell consists of a cell wall for structural rigidity and tough environmental conditions. The cell wall consists of three layers. 
  • The primary cell wall
  • secondary cell wall
  • middle lamella.
• The primary wall is composed of up to 50% Hemicellulose, cellulose 25%, and other smaller amounts of pectic substances, non-polysaccharides, fats, and proteins. The primary wall is the cellulose-containing layer laid down by cells that are dividing and growing.
• The secondary wall is composed of Lignin. Secondary cell walls provide additional protection to cells and rigidity and strength to the larger plant. Lignin makes the wall thick and rigid.
• Middle lamella is composed of Pectin. The middle lamella serves as a cementing layer between the primary walls of adjacent cells. The two cells can be separated from each other by the dissolution of the middle lamella by proteolytic enzymes.

So, The plant cell wall is made up of cellulose and hemicellulose..

The correct answer is Gluten.

Key Points

• Gluten
  • The protein which is naturally found in some grains including wheat, barley and rye is Gluten.
  • Although the term "gluten" is frequently solely used to describe proteins found in wheat, it is actually used in medical literature to describe a combination of prolamin and glutelin proteins that are found naturally in all grains and have been shown to be capable of causing celiac disease.
  • Triticeae glutens in particular have outstanding viscoelastic and adhesive properties that give the dough its elasticity, help it rise and hold its shape, and frequently produce a chewy texture in the final product. 

Additional Information

• Proteins
  • Large, intricate molecules known as proteins play a variety of vital functions in the body.
  • They are crucial for the structure, operation, and control of the body's tissues and organs and carry out the majority of their job inside cells.
  • Plant-based foods (fruits, vegetables, grains, nuts, and seeds) frequently lack one or more essential amino acids, but animal-based foods (meat, chicken, fish, eggs, and dairy products) are frequently good sources of complete protein.

The correct answer is Hibiscus and Mustard.

Key Points

• Hibiscus has both male and female reproductive parts in the same flower.
• The male reproductive parts are the stamens, which produce pollen.
• The female reproductive parts are the pistil, which contains the ovary and stigma.

Additional Information

• Mustard also has both male and female reproductive parts in the same flower. The male reproductive parts are the stamens, which produce pollen. The female reproductive parts are the pistil, which contains the ovary and stigma.
•  Watermelon has male flowers and female flowers and Papaya, on the other hand, has unisexual flowers. This means that male and female reproductive parts are in separate flowers.
• Papaya has separate male and female flowers on the same plant, so the individual flowers are not bisexual.

The correct answer is (A - III), (B - IV), (C - I), (D - II).

Key Points

• Vascular tissue or complex tissue is characteristic of plants.
• Transport in plants occurs by the xylem and phloem.
• The xylem conducts water, and the phloem conducts food.

Transpiration:

• It is the loss of water from the stomata.
• The exchange of gases takes during transpiration.
• It builds up the transpiration pull, and water is absorbed from the roots.

Osmosis:

• Diffusion of water across a semi-permeable membrane.
• It occurs from high concentration to low concentration along the gradient.
• It is downhill transport and does not require any energy.

Translocation:

• Bulk flow of substances.
• It is also known as mass flow.
• It occurs with the vascular tissue, such as the xylem and phloem.

Ascent of sap:

• It is the transport of water from root to shoot.
• It is the flow of water against gravity.
• Here upward flow of water takes place.

Additional Information 

Below is the pictorial representation of osmosis

Explanation:

Cell: 

• The cell is the fundamental unit of life. All the life activities are carried out by cells.
• The organisms are classified based on the number of cells present in them.
• Unicellular organisms are single-celled, while multicellular organisms have a large number of cells. 
• Differences between the plant cell and animal:
  • ​The cell wall is present in Plant cells while it is absent in an animal cells. A cell wall gives mechanical support to a plant cell. 
  • Plants have both a cell wall that is made up of cellulose and a cell membrane (plasma membrane). The cell wall is, a rigid membrane matrix found on the surface of all plant cells whose primary role is to protect the cell and its content. 
  • Plant cells have a large central vacuole that can occupy up to 90% of the cell’s volume. Animal cells may have many small vacuoles, a lot smaller than the plant cell. 

So, both statement is incorrect.

Concept : 

Edible plants:

• An edible item is any item that is safe for humans to eat.
• Nonpoisonous items found in nature – such as mushrooms, insects, seaweed, and so forth – are referred to as edible.
• Below are examples of seeds, roots, leaves, flowers, fruit, and stem.

Non Edible plants:

• The plant parts which humans cannot eat are called non-edible. 
• Non Edible plants use for shampoo, make-up, laundry detergent, and decoration purposes.

Explanation :

​Banana : 

• A banana is an elongated, edible fruit.
• The roots of the banana plants are the only parts that are not consumed as food by humans. 
• The banana plant has numerous edible parts, such as the inner stem, flower, and fruit.
• The banana flower and the stem are eaten in most parts of northeast India as a vegetable.
• The leaf is used to serve food.
• The only non-edible part of the banana plant is its root.

​Thus, ​the part of a banana plant not used as food is the root. 

The correct answer is A, B, D.

Concept:

• Fungi are eukaryotic organisms that include yeasts, moulds, and mushrooms.
• These organisms belong to the kingdom Fungi.
• The organisms found in the Kingdom Fungi have a cell wal.
• Among living organisms, they are classified as heterotrophs.

Explanation:
A. They are plants (TRUE)

• Fungi are plants that do not have chlorophyll.
• Fungi have a cell wall made which is made of chitin and obtain nutrients through absorption. 
• They are unable to photosynthesis because they lack chlorophyll.
• Fungi are either decomposers or parasites. Decomposers obtain their nutrients from decomposing biological matter

B. They cannot perform photosynthesis (TRUE)

• Fungi do not perform photosynthesis because fungi do not contain the green pigment chlorophyll.
• Fungi obtain their food by absorbing dissolved molecules and secreting digestive enzymes into their surroundings.

C. All fungi are unicellular (FALSE)

• Fungi are both unicellular and multicellular.
• With the exception of yeast, most fungi are multicellular. Yeast are unicellular.

D. some fungi help in producing antibiotics (TRUE)

• Antibiotics can be obtained naturally from bacteria or fungi (moulds are a type of fungi) or synthesized in laboratories.
• Alexander Fleming discovered penicillin in 1928, derived from the fungus Penicillium Notatum (a type of fungi).

Explanation:

• Microorganisms are living organisms that cannot be seen by the human eye. 
• Bacteria, fungi, protozoa, and some algae are major groups of microorganisms. 
• Viruses are also microscopic but they are behaving as living being only inside a host body. 
• Some microorganisms are useful while some are harmful to human beings. Microorganisms are used for various purposes like fermentation, nitrogen fixation and preparation of certain antibiotics. 
• Microorganisms can be both unicellular and multicellular. 
• Bacteria and some algae are unicellular, while some of algae, fungi etc are multicellular. 
• Fungi reproduce inside the cells of the host organism. This is wrong as the statement suits for the virus. 

So the correct option is 'Fungi reproduce inside the cells of the host organism.'

The correct answer is Iron.

• Iron is classified as a micronutrient and not as a macronutrient.

Key Points

• There are 17 elements which are required for the sustained growth of plants. 
• Out of these 17 elements, 9 are classified as macronutrients and 8 are classified as micronutrients.
• Macronutrients:
  • Carbon, hydrogen, oxygen, nitrogen, sulphur, phosphorous, potassium, magnesium and calcium.
  • These elements are required in large amounts for plant growth.
• Micronutrients: 
  • Iron, zinc, copper, nickel, manganese, boron, molybdenum and chlorine.
  • The elements are required in small quantities.

Important Points 

• Critical elements:
  • Nitrogen, phosphorous and potassium are called critical elements, as these are generally lacking in soil. Hence fertility of the soil is affected.

Additional Information

• Nitrogen:
  • It helps in the formation of protein and nucleic acids in plants.
• Sulphur:
  • It promotes the growth of roots and seeds in plants.
  • A lack of sulphur turns the leaves yellow and fruits will not flourish.
• Phosphorus:
  • They are found in nucleic acids and phospholipids of plant cells.
  • They help in seed formation and maturity of fruits.
• Potassium:
  • It helps in the general growth of plants.
  • Lack of potassium causes blights on plant leaves and protein synthesis is disrupted.
• Iron:
  • It plays a significant role in plant respiration.
  • Found mainly in chromatids and protoplasm of plant cells.
  • Lack of iron in plant causes chlorosis.