Structural Organisation in Animals: Class 11 Biology Q&A
19 free answers on Structural Organisation in Animals (Biology) for Class 11 students, across CBSE, ICSE and State boards. Includes questions such as “what is notochord in biology”, “What is cork in biology”, “What is anatomy in biology”.
Question & Answer
Questions
- BiologyClass 11All
what is notochord in biology
The notochord is a tube-shaped structure filled with extracellular fluid and cells. The origin of this structure had huge implications for the movement and locomotion of organisms. This provided some strength to organisms to move around and use muscles effectively. The evolution of notochord gave rise to a new set of organisms we call Chordates. This allowed them advantages that further strengthened them. Later on, the notochord got replaced by a cartilaginous vertebral column. This later on
- BiologyClass 11All
What is cork in biology
The cork cambium, also known as cambia or cambiums, is a tissue that makes up the epidermis in many vascular plants. Between the cork and the major phloem, it is one of the numerous layers of bark. A lateral meristem called the cork cambium is in charge of the secondary growth that takes the place of the epidermis in roots and stems. It is present in several monocots, gymnosperms, and many herbaceous dicots (monocots usually lack secondary growth). It is a part of the plant's meristem, a grou
- BiologyClass 11All
What is anatomy in biology
Anatomy is the study of the internal structure of the human body. It is a field of study examining the organs, bones, structures, and cells found in people and animals. Physiology is a closely connected scientific field. The study of how typically functioning living things work. For instance, how the human body and its organs work can help us comprehend how various body parts work, but understanding anatomy is crucial for physiology. By the 1600s, organs and cells were magnified using
- BiologyClass 11All
What is the difference between endocrine and exocrine glands?
Endocrine and exocrine glands are two types of glands in the body that play different roles in maintaining various physiological functions. Here are five key differences between them: Mode of Secretion: Endocrine Glands: These glands secrete hormones directly into the bloodstream. The hormones then travel throughout the body to target organs and tissues, where they exert their effects. Exocrine Glands: These glands secrete their products (such as enzymes, mucus, sweat,
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What is parenchyma?
Parenchyma is a type of simple plant tissue that makes up the bulk of various plant organs, including leaves, stems, roots, and fruits. It serves several essential functions within the plant. Parenchyma cells are characterized by their thin cell walls, large central vacuoles, and the ability to undergo various physiological processes. Key characteristics and functions of parenchyma tissue: Cell Structure: Parenchyma cells have primary cell walls that ar
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What are villi What is their location and function?
Villi (singular: villus) are small, finger-like projections that line the inner surface of the small intestine. They are specialized structures that significantly increase the surface area of the intestinal lining, serving important functions in the process of digestion and nutrient absorption. Location: Villi are found in the mucous membrane lining the inner wall of the small intestine. They are most abundant in the jejunum and ileum, the two lower parts of the small
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Give any two distinctive characteristics of chordates.
Two defining characteristics of phylum Chordata (present at least during embryonic development): Notochord: A flexible, rod-like supporting structure running along the back (dorsal side) of the organism. In primitive chordates and embryos, it provides skeletal support. In vertebrates, it's largely replaced by the vertebral column (backbone) during development, though remnants persist as intervertebral discs.
- BiologyClass 11All
Is tissue damage serious?
Tissue damage can range from minor and self-healing to serious and life-threatening, depending on the extent of damage, which tissues are affected, whether vital organs are involved, and the underlying cause. Severity assessment requires professional medical evaluation. Minor tissue damage includes superficial cuts, bruises, mild muscle strains, and small burns—these typically heal without intervention through normal repair processes. Such injuries cause temporary discomfort but
- BiologyClass 11All
Which type of tissue is most?
The most abundant tissue type in the human body is connective tissue, comprising approximately 45-50% of total body mass and existing in diverse forms throughout virtually every body region. Connective tissue's predominance reflects its variety and ubiquity. It includes bone (providing skeletal support), cartilage (cushioning joints), adipose tissue (storing energy), blood (transporting materials), lymphatic tissue (immune function), and various forms of connective tissue proper: loos
- BiologyClass 11All
Where is your hardest tissue?
Your hardest tissue is located in your teeth, specifically the enamel covering the crown portion visible above the gums. Tooth enamel is the hardest substance in the entire human body, even harder than bone. Enamel consists of approximately 96% minerals, primarily hydroxyapatite (a crystalline calcium phosphate), making it exceptionally hard and resistant to wear. This hardness protects teeth during the tremendous forces generated while chewing—molars can exert pressure exceedin
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Why is tissue needed?
Tissue is needed because it enables the cellular specialization and organization essential for complex multicellular life. Without tissue-level organization, organisms would be limited to single-celled or simple multicellular forms incapable of sophisticated functions. Tissues provide critical capabilities through division of labor. Individual cells have limited size and functional range, but when similar cells organize into tissues, they perform specialized roles with far greater eff
- BiologyClass 11All
What happens when tissue is damaged?
When tissue is damaged, the body initiates a complex healing response involving inflammation, cell proliferation, and tissue remodeling. This process aims to restore structure and function, though outcomes vary depending on tissue type and damage severity. The healing process begins immediately with hemostasis (blood clotting) to stop bleeding from damaged blood vessels. Platelets aggregate at the injury site, forming a clot that prevents blood loss and creates a temporary barrier. Wi
- BiologyClass 11All
Which is the largest tissue in the body?
The largest tissue in the body is connective tissue, which comprises approximately 45-50% of total body mass and exists throughout virtually every body region. However, if asking about a specific tissue structure, the skin (composed primarily of epithelial and connective tissues) represents the largest organ. Connective tissue's abundance reflects its diversity and ubiquity. It includes bone (providing skeletal framework), cartilage (cushioning joints), adipose tissue (storing energy)
- BiologyClass 11All
Are there 78 or 79 organs?
The question of whether there are 78 or 79 organs stems from recent debate over whether the mesentery (tissue connecting the intestine to the abdominal wall) qualifies as a distinct organ. However, organ counts vary depending on classification criteria, and there's no universally agreed number. The mesentery controversy arose when researchers proposed in 2017 that this connective tissue structure should be classified as an organ due to its continuous structure and distinct functions b
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What tissues can be attacked by your immune system?
Your immune system can potentially attack virtually any tissue in the body during autoimmune conditions, though certain tissues are more commonly targeted. Autoimmune diseases demonstrate the immune system's capacity to mistakenly identify self-tissues as threats. Commonly attacked tissues include joints (rheumatoid arthritis), pancreatic insulin-producing cells (type 1 diabetes), thyroid tissue (Graves' disease, Hashimoto's thyroiditis), nervous tissue myelin coating (multiple sclero
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What is a tissue disorder?
A tissue disorder is any condition affecting tissue structure or function, leading to impaired health. These disorders range from localized injuries to systemic diseases affecting multiple tissue types throughout the body. Tissue disorders are classified in various ways. Inflammatory tissue disorders involve excessive or inappropriate immune responses causing tissue swelling, pain, and damage examples include arthritis (joint tissue inflammation), tendinitis (tendon inflammation), and
- BiologyClass 11All
Write the chemical composition of cell wall of: (a) Bacteria (b) Fungus (c) Alga
[Previously answered in question 39 - refer to detailed table] Brief summary: (a) Bacteria: Peptidoglycan (NAG-NAM cross-linked by peptides) (b) Fungus: Chitin (β-1,4-linked N-acetylglucosamine) + glucans (c) Alga: Cellulose + galactans, mannans, minerals (calcium carbonate); some with silica (diatoms)
- BiologyClass 11All
Explain the terms related to a prokaryotic cell: (a) Mesosomes (b) Chromatophores
(a) Mesosomes Definition: Specialized invaginations (infoldings) of the prokaryotic plasma membrane extending into cytoplasm Structure: Complex, convoluted membranous structures (vesicular, tubular, or lamellar) Proposed functions (debated): Respiration: Increase surface area for respiratory enzymes (electron transport chain)</l
- BiologyClass 11All
Define gram negative bacteria.
Gram-negative bacteria are prokaryotes that do not retain the crystal violet stain in the Gram staining procedure and appear pink/red after counterstaining with safranin. They possess a thin peptidoglycan layer (2–3 nm) and an outer lipopolysaccharide membrane. Examples: E. coli, Salmonella, Vibrio cholerae