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The correct answer is Nerve cells.

Key Points

• Nerve cells, also known as neurons, are specialized cells that transmit information throughout the body.
• Neurons have unique structures called dendrites and axons that help in the conduction of nerve impulses.
• Dendrites receive signals from other neurons and convey this information to the cell body.
• Axons transmit signals away from the cell body to other neurons, muscles, or glands.
• Neurons are integral to the nervous system, which includes the brain, spinal cord, and peripheral nerves.

Additional Information

• Neurons
• Neurons are the basic building blocks of the nervous system.
• They are highly specialized for the processing and transmission of cellular signals.
• The human brain contains approximately 86 billion neurons.
• Synapses
• Synapses are the junctions where neurons communicate with each other.
• They can be chemical or electrical.
• Chemical synapses use neurotransmitters to transmit signals across the synaptic cleft.
• Myelin Sheath
• The myelin sheath is a fatty layer that covers the axons of many neurons.
• It increases the speed at which electrical impulses travel along the axon.
• Diseases such as multiple sclerosis can damage the myelin sheath, leading to neurological problems.
• Glial Cells
• Glial cells are non-neuronal cells that provide support and protection for neurons.
• They are essential for maintaining homeostasis, forming myelin, and providing support and protection for neurons.
• Types of glial cells include astrocytes, oligodendrocytes, and microglia.

The correct answer is Phloem fibres.

Key Points

• Phloem fibres, also known as bast fibres, are the only dead cells in the phloem tissue.
• They provide mechanical support to the plant.
• These fibres are elongated, thick-walled, and lignified cells.
• Unlike other phloem cells, they lose their protoplasm at maturity.

Additional Information

• Phloem Tissue:
• Phloem is a complex tissue in vascular plants responsible for the transport of organic nutrients, particularly sucrose, from source tissues (leaves) to sink tissues (roots, flowers, fruits).
• It consists of several types of cells: sieve elements, companion cells, phloem fibres, and phloem parenchyma.
• Sieve Elements:
• Sieve elements are the major conducting cells in phloem, consisting of sieve tubes in angiosperms and sieve cells in gymnosperms.
• They are living cells at maturity but lack a nucleus, ribosomes, and other organelles.
• Companion Cells:
• Companion cells are closely associated with sieve tube elements in angiosperms.
• They help in the maintenance and functioning of sieve tube elements and are living cells with a dense cytoplasm and a prominent nucleus.
• Phloem Parenchyma:
• Phloem parenchyma cells are living cells that store and transport nutrients within the phloem.
• They also help in the repair and regeneration of phloem tissue.

The correct answer is Amoeba exhibit regeneration..

Key Points

• Regeneration is a process whereby some organisms can regrow lost or damaged parts of their body.
• Specialised cells are responsible for regeneration and they multiply rapidly to form new tissues.
• Organisms such as Hydra and Planaria are known for their remarkable regenerative capabilities.
• Amoeba, being a unicellular organism, does not exhibit regeneration as it reproduces by binary fission.

Additional Information

• Binary Fission:
• A type of asexual reproduction where a single organism divides into two equal parts, each becoming a new organism.
• Amoeba reproduces through binary fission.
• Hydra:
• A small, freshwater organism known for its ability to regenerate entire bodies from small pieces.
• Regeneration occurs through the proliferation of specialized cells called interstitial cells.
• Planaria:
• A type of flatworm capable of regenerating any part of its body.
• Planaria utilize pluripotent stem cells known as neoblasts for regeneration.
• Specialised Cells:
• These cells have the ability to divide and differentiate to form various types of tissues and organs.
• They play a crucial role in the regeneration process.

The correct answer is Regulation of hearing.

Key Points

• The medulla oblongata is responsible for regulating essential autonomic functions of the body.
• It controls functions such as breathing, heart rate, and blood pressure.
• Other functions of the medulla include regulating reflex actions like vomiting, coughing, sneezing, and swallowing.
• Regulation of hearing is primarily managed by the auditory cortex in the temporal lobe of the brain, not the medulla.

Additional Information

• Medulla Oblongata
• The medulla oblongata is a section of the brainstem that connects the brain to the spinal cord.
• It plays a crucial role in transmitting signals between the brain and the spinal cord.
• Autonomic Nervous System
• The autonomic nervous system controls involuntary physiological functions such as heart rate, digestion, respiratory rate, and pupillary response.
• It is divided into the sympathetic and parasympathetic systems.
• Auditory Cortex
• The auditory cortex is located in the temporal lobe and is responsible for processing auditory information.
• It is crucial for the perception and interpretation of sounds.
• Brainstem
• The brainstem consists of the midbrain, pons, and medulla oblongata.
• It controls essential life functions such as breathing, heartbeat, and blood pressure.

The correct answer is Ligament.

Key Points

• Ligaments are a type of connective tissue that connect bones to other bones in joints.
• They are composed of dense, fibrous connective tissue that provides stability and support to joints.
• Ligaments are crucial for maintaining the structure of the skeletal system and enabling proper movement.
• They contain collagen fibers, which provide tensile strength and elasticity to withstand various types of stresses.

Additional Information

• Tendons
• Tendons are connective tissues that connect muscles to bones.
• They are composed mainly of collagen fibers and are designed to withstand tension.
• Tendons play a vital role in transmitting the force generated by muscles to bones, facilitating movement.
• Cartilage
• Cartilage is a flexible connective tissue found in various parts of the body, including joints, ear, and nose.
• It provides cushioning and reduces friction between bones in joints.
• There are three types of cartilage: hyaline, elastic, and fibrocartilage, each serving different functions.
• Adipose Tissue
• Adipose tissue, or body fat, is a type of connective tissue that stores energy in the form of fat.
• It also provides insulation and cushioning to protect organs and tissues.
• Adipose tissue is found beneath the skin, around internal organs, and in bone marrow.
• Fibrous Connective Tissue
• Fibrous connective tissue is characterized by a dense arrangement of collagen fibers.
• It includes ligaments, tendons, and the dermis layer of the skin.
• This type of tissue provides strength, support, and flexibility to various body structures.

The correct answer is Dura mater.

Key Points

• Dura mater is the thick, durable membrane closest to the skull.
• It is the outermost of the three layers of the meninges that surround the brain and spinal cord.
• The dura mater provides a tough protective layer for the brain.
• It is composed of dense connective tissue and has an outer periosteal layer and an inner meningeal layer.

Important Points

• Arachnoid mater: It is the middle layer of the meninges, situated between the dura mater and pia mater. It is named for its web-like appearance.
• Thalamic mater: This term is incorrect in the context of the meninges. There is no such structure as "thalamic mater" in the anatomy of the brain.
• Pia mater: It is the delicate innermost layer of the meninges that clings tightly to the surface of the brain and spinal cord, following all their contours.

Additional Information

• Meninges: The three layers of protective tissue called the dura mater, arachnoid mater, and pia mater that surround the neuraxis (the axis of the central nervous system).
• Cerebrospinal Fluid (CSF): The clear fluid found in the brain and spinal cord, which acts as a cushion to protect these organs from injury.
• Subarachnoid Space: The space between the arachnoid mater and the pia mater, which is filled with cerebrospinal fluid.

The correct answer is 1972.

Key Points

• The fluid mosaic model was proposed by S.J. Singer and G.L. Nicolson in 1972.
• This model describes the structure of cell membranes as a mosaic of components that gives the membrane a fluid character.
• It emphasizes that the cell membrane is flexible and constantly in motion, rather than being static.
• The model was revolutionary for illustrating the dynamic nature of the lipid bilayer and the embedded proteins.

Additional Information

• Lipid Bilayer:
• A double layer of lipids that forms the core structure of the cell membrane.
• Each lipid molecule has a hydrophilic (water-attracting) head and two hydrophobic (water-repelling) tails.
• Integral Proteins:
• Proteins that are embedded within the lipid bilayer.
• They can span the entire membrane (transmembrane proteins) or be attached to only one side.
• Peripheral Proteins:
• Proteins that are attached to the exterior or interior surfaces of the lipid bilayer.
• They are not embedded within the lipid bilayer.
• Fluidity:
• Refers to the viscous nature of the lipid bilayer, allowing lateral movement of molecules within the layer.
• Fluidity is influenced by temperature and the composition of the lipid molecules.
• Mosaic Nature:
• Describes the heterogeneous composition of the cell membrane, including lipids, proteins, and carbohydrates.
• These components are not uniformly distributed, contributing to the diverse functionality of the cell membrane.

The correct answer is style.

Key Points

• The pollen tube grows from the pollen grain and travels through the style to reach the ovary.
• The style is a slender stalk that connects the stigma to the ovary in the flower.
• The primary function of the style is to provide a pathway for the pollen tube to deliver sperm cells to the ovule.
• The growth of the pollen tube through the style is a crucial step in the fertilization process in flowering plants.

Additional Information

• Stigma
• The stigma is the part of the pistil where pollen germinates.
• It is typically sticky, aiding in the capture of pollen grains.
• Ovary
• The ovary is the enlarged basal portion of the pistil where ovules are produced.
• After fertilization, the ovary develops into a fruit.
• Anther
• The anther is the part of a stamen that contains the pollen.
• It is typically located at the top of the filament.
• Filament
• The filament is the stalk that supports the anther in the stamen.
• It helps position the anther for effective pollen transfer.

The correct answer is Binary fission.

Key Points

• Binary fission is a form of asexual reproduction.
• In this process, a single organism divides into two equal parts.
• Each part develops into a new organism identical to the parent.
• This method is common in prokaryotic organisms like bacteria.
• It ensures rapid population growth in favorable environments.
• Binary fission occurs through simple mitotic cell division.
• Examples of organisms that reproduce by binary fission include Amoeba and Paramecium.

 Additional Information

• Regeneration
• Regeneration is the process by which organisms replace or restore lost or damaged tissues or body parts.
• It is seen in organisms like starfish, lizards, and planarians.
• Unlike binary fission, regeneration involves the formation of new tissues from the remaining part.
• Spore formation
• Spore formation is a method of asexual reproduction where an organism produces spores that develop into new individuals.
• This method is common in fungi, algae, and some bacteria.
• Spores are typically resistant to harsh environmental conditions.
• Budding
• Budding is an asexual reproduction method where a new organism grows from a bud on the parent organism.
• It is observed in organisms like yeasts and hydras.
• The new organism remains attached until it is mature and then detaches.

The correct answer is buds produced in the notches along the leaf margin.

Key Points

• Bryophyllum is known for its unique method of vegetative propagation through the production of buds in the notches along the leaf margin.
• These buds can grow into new plants when they fall off and find suitable conditions, such as moist soil.
• This type of vegetative propagation allows Bryophyllum to reproduce quickly and efficiently without the need for seeds.
• The buds along the leaf margins are called adventitious buds, which means they can develop into complete plants.

Additional Information

• Vegetative Propagation:
• It is a form of asexual reproduction in plants where new individuals arise without the production of seeds or spores.
• Common methods include the use of runners, tubers, bulbs, and plantlets.
• Adventitious Buds:
• These are buds that develop in unusual places, such as along the leaf margin or on roots, rather than at the tips of stems or in leaf axils.
• They have the potential to grow into complete plants, aiding in rapid vegetative propagation.
• Advantages of Vegetative Propagation:
• Allows for the rapid multiplication of plants.
• Ensures genetic uniformity, as the offspring are clones of the parent plant.
• Enables propagation of plants that do not produce viable seeds.
• Examples of Plants Using Vegetative Propagation:
• Potato (tubers), Onion (bulbs), Strawberry (runners), and Bryophyllum (leaf buds).