TLDR;
This YouTube video is a comprehensive Biology 2 marathon for 11th-grade students, focusing on Zoology. The lecture covers essential topics such as Kingdom Animalia, Cell Division, Tissues, Cockroach, Human Nutrition, Excretion and Osmoregulation, and Movement and Locomotion. The instructor provides detailed explanations, diagrams, and examples to aid understanding. Additionally, the video guides students on how to download notes from the PW app and join the PW Maharashtra WhatsApp channel for updates and notifications.
- Comprehensive coverage of Zoology topics for 11th grade.
- Guidance on accessing notes and important updates via the PW app and WhatsApp channel.
- Detailed explanations of key concepts with diagrams and examples.
Introduction [0:26]
The instructor, welcomes students to the Biology 2 marathon, emphasizing its importance for their final exams. She assures students that the session will cover all the topics they requested and mentions that the Botany part has already been completed in a previous marathon. She encourages students to stay engaged for the next six to seven hours and highlights that the marathon will significantly boost their final exam preparation.
Accessing Notes and Important Updates [2:42]
The instructor explains how to access notes from the PW app. Students need to download the app, sign in with their mobile number, and search for the 11th-grade batch to find the uploaded notes. She also introduces the PW Maharashtra WhatsApp channel, accessible via a QR code, which provides important notifications about classes and updates. She advises students to take 12th grade seriously, as it is crucial for board exams and future studies.
Marathon Topics [5:44]
The instructor outlines the topics to be covered in the marathon, including Kingdom Animalia, Cell Division, Tissues, Cockroach, Human Nutrition, Excretion and Osmoregulation, and Movement and Locomotion. She mentions that the session will likely last until 10 PM, but could extend to 11 PM or 12 AM, depending on the pace and student engagement.
Kingdom Animalia: Introduction and Classification [8:23]
The instructor begins with the definition of an animal: a multicellular, heterotrophic organism without a cell wall or chlorophyll. She lists the 11 major phyla of Kingdom Animalia: Porifera, Cnidaria, Ctenophora, Platyhelminthes, Aschelminthes, Annelida, Arthropoda, Mollusca, Echinodermata, Hemichordata, and Chordata. She explains that Porifera are the most primitive, while Chordata are the most advanced. The classification is based on levels of organization, symmetry, germinal layers, coelom, segmentation, and notochord.
Levels of Organization and Body Plans [15:35]
The instructor explains the levels of organization: cellular, tissue, organ, and organ system. She details the differences between cells and tissues, explaining that tissues are groups of cells performing a specific function. She also describes two body plans: blind sac (one opening for ingestion and egestion) and tube-within-a-tube (separate openings for mouth and anus).
Digestive and Circulatory Systems [22:56]
The instructor discusses the two types of digestive systems: incomplete (single opening) and complete (two openings). She then explains the two types of circulatory systems: open (blood directly contacts tissues) and closed (blood circulates within vessels), using the examples of cockroaches and humans, respectively.
Symmetry and Germinal Layers [40:30]
The instructor explains symmetry, differentiating between asymmetrical, radial, and bilateral symmetry. She also discusses germinal layers (ectoderm, mesoderm, and endoderm), explaining the difference between diploblastic (two layers) and triploblastic (three layers) animals.
Coelom and Segmentation [46:32]
The instructor defines the coelom (body cavity) and explains the three types of coelom organization: acoelomate (no coelom), pseudocoelomate (false coelom), and coelomate (true coelom). She also discusses metamerism or segmentation, where the body is divided into repeated segments, and the presence or absence of a notochord.
Phylum Porifera [52:43]
The instructor begins discussing specific phyla, starting with Porifera. She notes their cellular level of organization, asymmetrical or radial symmetry, absence of germ layers, and acoelomate condition. She describes their aquatic habitat, sedentary lifestyle, and the presence of intracellular digestion. A key feature is the water canal system with ostia (incurrent pores), spongocoel (central cavity), and osculum (excurrent pore). Choanocytes or collar cells line the spongocoel. Examples include Sycon, Spongilla (freshwater sponge), and Euspongia (bath sponge).
Phylum Cnidaria [1:01:29]
The instructor discusses Phylum Cnidaria, noting their tissue-level organization, radial symmetry, diploblastic nature, and acoelomate condition. They are mostly marine and can be sessile or free-swimming. Digestion is incomplete, with both intracellular and extracellular processes. A unique feature is the presence of tentacles with cnidoblasts or cnidocytes containing nematocysts (stinging cells). They exhibit two body forms: polyp (sessile, asexual) and medusa (free-swimming, sexual). Examples include Hydra, Adamsia, and Aurelia (jellyfish).
Phylum Ctenophora [1:10:52]
The instructor covers Phylum Ctenophora, noting their tissue-level organization, radial symmetry, diploblastic nature, and acoelomate condition. They are exclusively marine and solitary. Digestion is incomplete, with both intracellular and extracellular processes. A unique feature is locomotion via eight external rows of ciliated comb plates and the presence of bioluminescence. Examples include Ctenoplana and Pleurobrachia.
Phylum Platyhelminthes [1:14:56]
The instructor discusses Phylum Platyhelminthes, noting their organ and organ-system level of organization, bilateral symmetry, triploblastic nature, and acoelomate condition. They can be aquatic, endoparasitic, or free-living. Digestion is incomplete. A unique feature is dorsoventrally flattened bodies, excretion via flame cells or protonephridia, and hooks and suckers in parasitic forms. Examples include Taenia solium (tapeworm), Fasciola (liver fluke), and Planaria (free-living).
Phylum Aschelminthes [1:23:48]
The instructor covers Phylum Aschelminthes, noting their organ-system level of organization, bilateral symmetry, triploblastic nature, and pseudocoelomate condition. They can be aquatic, terrestrial, free-living, or parasitic. Digestion is complete. A unique feature is a syncytial epidermis, thick cuticle, and an excretory tube. Examples include Ascaris, Ancylostoma (hookworm), and Wuchereria (filarial worm).
Phylum Annelida [1:27:21]
The instructor discusses Phylum Annelida, noting their organ-system level of organization, bilateral symmetry, triploblastic nature, and coelomate condition. They can be terrestrial, freshwater, or marine, and free-living or parasitic. Digestion is complete. A key feature is a closed circulatory system, true segmentation, and locomotory organs like setae or parapodia. Examples include Pheretima (earthworm), Hirudinaria (leech), and Nereis.
Phylum Arthropoda [1:33:12]
The instructor covers Phylum Arthropoda, noting their organ-system level of organization, bilateral symmetry, triploblastic nature, and coelomate condition. They are cosmopolitan, found in various habitats. Digestion is complete. Respiration occurs via gills, book gills, tracheal systems, or book lungs. A key feature is jointed appendages, a body divided into head, thorax, and abdomen, and a chitinous cuticle. Examples include spiders, scorpions, crabs, prawns, and insects.
Phylum Mollusca [1:41:01]
The instructor discusses Phylum Mollusca, noting their organ-system level of organization, bilateral symmetry, triploblastic nature, and coelomate condition. They are mostly aquatic, with a few terrestrial species. Digestion is complete. Respiration occurs via gills or pulmonary sacs. A key feature is a body with a head, visceral mass, and muscular foot, a calcareous shell, and a mantle. Examples include Pila (apple snail), Pinctada (pearl oyster), Sepia (cuttlefish), Loligo (squid), and Octopus.
Phylum Echinodermata [1:45:34]
The instructor covers Phylum Echinodermata, noting their organ-system level of organization, radial symmetry (bilateral in larvae), triploblastic nature, and coelomate condition. They are exclusively marine. Digestion is complete, with a ventral mouth and dorsal anus. Respiration occurs via dermal branchiae or tube feet. A key feature is a body covered with spines, an endoskeleton of calcareous ossicles, and a water vascular system. Examples include Asterias (starfish), Echinus (sea urchin), Antedon (sea lily), and Ophiura (brittle star).
Phylum Hemichordata [1:52:53]
The instructor discusses Phylum Hemichordata, noting their organ-system level of organization, bilateral symmetry, triploblastic nature, and coelomate condition. They are exclusively marine. Digestion is complete. Respiration occurs via gills. A key feature is a worm-like cylindrical body with a proboscis, collar, and trunk, and a stomochord. Excretion occurs via a proboscis gland. Examples include Balanoglossus (tongue worm) and Saccoglossus.
Phylum Chordata [1:54:55]
The instructor covers Phylum Chordata, noting the presence of a notochord, dorsal nerve cord, and pharyngeal gill slits. The phylum is divided into three subphyla: Urochordata, Cephalochordata, and Vertebrata.
Subphylum Vertebrata: Cyclostomata [1:57:55]
The instructor discusses the class Cyclostomata, which includes jawless vertebrates. They are ectoparasites on some fishes, with an elongated body lacking scales and paired fins. They have 6-15 pairs of gill slits and a sucking, circular mouth. The cranium is cartilaginous, and circulation is closed. They are marine but migrate to freshwater for spawning. Examples include lampreys and hagfishes.
Subphylum Vertebrata: Chondrichthyes and Osteichthyes [2:01:13]
The instructor compares Chondrichthyes (cartilaginous fishes) and Osteichthyes (bony fishes). Chondrichthyes are marine predators with a cartilaginous endoskeleton and placoid scales. They lack an air bladder and must swim constantly to avoid sinking. Osteichthyes can be marine or freshwater, with a bony endoskeleton and cycloid or ctenoid scales. They have an air bladder for buoyancy. Both are poikilotherms with a two-chambered heart.
Subphylum Vertebrata: Amphibia [2:06:54]
The instructor discusses Class Amphibia, noting that they live in aquatic and terrestrial habitats and need water for breeding. They have a body with a head and trunk, moist skin without scales, and typically two pairs of limbs. A tympanum is present, and they have a three-chambered heart. Respiration occurs via gills in the larval stage and lungs and skin in adults. They are oviparous with external fertilization.
Subphylum Vertebrata: Reptilia [2:08:54]
The instructor discusses Class Reptilia, noting that they are the first true terrestrial vertebrates. They can be terrestrial, semi-aquatic, or aquatic. Locomotion is via limbs, though some (like snakes) are limbless. The skin is dry and non-glandular, with scales. The heart has two complete auricles and incompletely partitioned ventricles (except for crocodiles, which have a four-chambered heart). Fertilization is internal, and they are mostly oviparous.
Subphylum Vertebrata: Aves [2:12:47]
The instructor discusses Class Aves (birds), noting the presence of feathers and a beak. Forelimbs are modified into wings. The skin is dry and without glands, except for an oil gland at the base of the tail. Limbs have scales and are modified for walking, swimming, or clasping. Bones are long, hollow, and pneumatic. A tympanum is present, and they have a four-chambered heart. They are homeotherms (warm-blooded).
Subphylum Vertebrata: Mammalia [2:17:48]
The instructor discusses Class Mammalia, noting the presence of mammary glands for milk production and skin with hair. They have two pairs of limbs for various forms of locomotion. External pinnae are present, and they have a four-chambered heart. They are homeotherms. Teeth are heterodont, thecodont, and diphyodont. Respiration is via lungs. They are viviparous (except for monotremes like echidnas and platypuses).
Cell: The Unit of Life - Introduction and Cell Theory [2:20:37]
The instructor introduces the cell as the fundamental structural and functional unit of all living organisms. Robert Hooke discovered cells in cork, while Anton van Leeuwenhoek first observed live cells. Schleiden and Schwann formulated the cell theory, stating that all plants and animals are composed of cells and their products. Rudolf Virchow modified the cell theory, stating that new cells arise from pre-existing cells (omnis cellula e cellula).
Cell Overview and Types [2:23:04]
The instructor provides an overview of cell components, including cytoplasm and ribosomes. She notes that the smallest cell is Mycoplasma, the largest isolated single cell is the egg of an ostrich, and the longest cell is a nerve cell. Bacteria range from 3-5 μm, while human RBCs are about 7.0 μm in diameter. Cell shapes vary based on function. She differentiates between prokaryotic (no membrane-bound nucleus or organelles) and eukaryotic cells.
Prokaryotic Cells: Structure and Components [2:25:17]
The instructor discusses prokaryotic cells, which include bacteria, blue-green algae, and mycoplasmas. They are smaller and multiply more rapidly than eukaryotic cells. The basic shapes include bacillus (rod-like), coccus (spherical), vibrio (comma-shaped), and spirillum (spiral). Key components include the cell envelope (glycocalyx, cell wall, plasma membrane), mesosomes, chromatophores, nucleoid, flagella, pili or fimbriae, ribosomes, and inclusion bodies.
Prokaryotic Cell Components: Cell Envelope and Mesosomes [2:26:13]
The instructor details the cell envelope, a protective covering composed of the glycocalyx (outer layer), cell wall (middle layer), and plasma membrane (inner layer). The glycocalyx varies in thickness and composition. The cell wall provides shape and structural support. The plasma membrane is selectively permeable. Mesosomes are formed by infoldings of the plasma membrane and aid in cell wall formation, DNA replication, chromosome distribution, respiration, and secretion.
Prokaryotic Cell Components: Nucleoid, Flagella, and Ribosomes [2:28:38]
The instructor explains that the nucleoid is a non-membrane-bound region containing the circular genomic DNA. Many bacteria have plasmids, small circular DNA molecules that confer unique characteristics. Flagella aid in motility. Fimbriae are small structures that also help in motility. Ribosomes are associated with the plasma membrane and are 70S in prokaryotes (50S and 30S subunits). They are the site of protein synthesis.
Prokaryotic Cell Components: Inclusion Bodies [2:30:55]
The instructor describes inclusion bodies as non-membrane-bound structures that store reserve materials in the cytoplasm of prokaryotes. Examples include phosphate granules and gas vacuoles.
Eukaryotic Cells: Structure and Organelles [2:32:16]
The instructor introduces eukaryotic cells, which have membrane-bound nuclei and organelles. They include protist, fungal, plant, and animal cells. The membrane provides clear compartmentalization of the cytoplasm. Genetic material is organized into chromosomes. Key organelles include the cell membrane, cell wall, endomembrane system (endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles), mitochondria, plastids, ribosomes, cytoskeleton, cilia and flagella, centrioles, nucleus, and microbodies.
Cell Membrane: Structure and Function [2:33:53]
The instructor explains that the cell membrane is composed of a lipid bilayer, proteins, and carbohydrates. Lipids are mainly phosphoglycerides with a polar head and hydrophobic tails. She details the fluid mosaic model proposed by Singer and Nicolson, where the quasi-fluid nature of lipids enables lateral movement of proteins. The cell membrane is selectively permeable and aids in cell growth and formation.
Cell Membrane: Transport Mechanisms [2:36:53]
The instructor discusses transport mechanisms across the cell membrane: passive transport (no ATP required, driven by concentration gradients), active transport (ATP required), and facilitated diffusion (transport via membrane proteins).
Cell Wall and Endomembrane System [2:39:10]
The instructor explains that the cell wall provides shape, protects against mechanical damage and infection, facilitates cell-to-cell connections, and acts as a barrier. The endomembrane system includes the endoplasmic reticulum (ER), Golgi complex, lysosomes, and vacuoles, all working in coordination.
Endoplasmic Reticulum and Golgi Apparatus [2:40:31]
The instructor details the endoplasmic reticulum (ER), which comes in two types: rough ER (RER) with ribosomes for protein synthesis and smooth ER (SER) for lipid synthesis. The Golgi apparatus, discovered by Camillo Golgi, consists of cisternae arranged concentrically with cis (forming) and trans (maturing) faces. It aids in protein packaging.
Lysosomes and Vacuoles [2:42:07]
The instructor explains that lysosomes are membrane-bound vesicles formed by the Golgi apparatus, containing hydrolytic enzymes for digesting carbohydrates, lipids, proteins, and nucleic acids. Vacuoles are membrane-bound spaces in the cytoplasm, containing water, sap, excretory products, and other materials. In plant cells, vacuoles can occupy up to 90% of the cell volume.
Mitochondria and Plastids [2:43:50]
The instructor discusses mitochondria, the powerhouses of the cell, where ATP synthesis occurs. Plastids are present in all plant cells and contain pigments. They are classified into chloroplasts, chromoplasts, and leucoplasts.
Cytoskeleton and Nucleus [2:45:52]
The instructor explains that the cytoskeleton is a network of filamentous proteinaceous structures in the cytoplasm, providing mechanical support, motility, and maintaining cell shape. Cilia and flagella aid in movement. The nucleus, first described by Robert Brown, contains chromosomes with centromeres and kinetochore plates. Chromosomes carry genetic material.
Chromosomes and Microbodies [2:48:34]
The instructor details the four types of chromosomes based on centromere position: metacentric, submetacentric, acrocentric, and telocentric. Microbodies are membrane-bound vesicles containing various enzymes, present in both plant and animal cells.
Cell Cycle and Cell Division: Introduction and Phases [3:13:49]
The instructor introduces the cell cycle, the life period of a cell during which it synthesizes DNA and divides. The cell cycle has two basic phases: interphase and M phase. Interphase includes cell growth and DNA synthesis, lasting more than 95% of the cycle. It consists of G1 phase (growth), S phase (DNA synthesis), and G2 phase (preparation for mitosis).
Cell Cycle: Interphase Details [3:17:39]
The instructor details the events in each phase of interphase. In the G1 phase, there is continuous cell growth, metabolic activity, and preparation for DNA replication. In the S phase, DNA replicates, doubling the amount of DNA per cell, but the chromosome number remains the same. In animal cells, replication begins in the nucleus, and the centriole duplicates in the cytoplasm. In the G2 phase, cell growth continues, RNA and protein synthesis continues, and the cell prepares for mitosis.
Cell Cycle: M Phase (Mitosis) [3:20:43]
The instructor explains the M phase, which represents actual cell division or mitosis. It includes karyokinesis (nuclear division) and cytokinesis (cytoplasmic division). She notes that not every cell in the body undergoes mitosis. Some cells, like heart cells, do not divide, while others divide only occasionally to replace damaged or dead cells. A G0 phase exists for cells that do not divide further.
Mitosis: Stages of Karyokinesis [3:23:26]
The instructor details the four stages of karyokinesis: prophase, metaphase, anaphase, and telophase. In prophase, chromosomes condense. In metaphase, chromosomes align at the equatorial plate and attach to spindle fibers. In anaphase, sister chromatids separate and move to opposite poles. In telophase, the nuclear envelope reforms, and cytokinesis occurs, dividing the cytoplasm.
Mitosis: Cytokinesis and Significance [3:26:20]
The instructor explains cytokinesis, where the cell divides into two daughter cells. In animal cells, a cleavage furrow forms, while in plant cells, a cell plate forms. The significance of mitosis includes producing diploid daughter cells with identical genomes, maintaining the same chromosome number in somatic cells, aiding in growth, and repairing and replacing damaged cells.
Meiosis: Introduction and Stages [3:29:17]
The instructor introduces meiosis, a division of diploid germ cells that reduces the chromosome number by half, forming haploid daughter cells or gametes. Meiosis occurs in two steps: meiosis I and meiosis II.
Meiosis I: Prophase I [3:33:17]
The instructor details the five stages of prophase I: leptotene, zygotene, pachytene, diplotene, and diakinesis. In leptotene, chromosomes condense. In zygotene, homologous chromosomes pair up. In pachytene, crossing over or recombination occurs. In diplotene, chiasmata (X-shaped structures) become visible. In diakinesis, chromosomes fully condense and separate.
Meiosis I: Metaphase I, Anaphase I, and Telophase I [3:34:47]
The instructor explains that in metaphase I, homologous chromosome pairs align at the equatorial plate. In anaphase I, homologous chromosomes separate and move to opposite poles. In telophase I, the cell divides, forming two haploid cells.
Meiosis II: Stages and Significance [3:36:03]
The instructor details meiosis II, which is similar to mitosis. In prophase II, chromosomes condense. In metaphase II, chromosomes align at the equatorial plate. In anaphase II, sister chromatids separate and move to opposite poles. In telophase II, the cells divide, resulting in four haploid daughter cells. The significance of meiosis includes conserving the chromosome number in each species and generating genetic variation through crossing over.
Animal Tissues: Introduction and Types [3:43:35]
The instructor introduces animal tissues, defined as groups of similar cells performing a specific function. The four main types of tissues are epithelial, connective, muscular, and neural.
Epithelial Tissue: Types and Functions [3:44:47]
The instructor discusses epithelial tissue, which can be simple (single layer) or compound (multiple layers). Simple epithelial tissue includes squamous, cuboidal, columnar, ciliated, and glandular types. Squamous epithelium is flat and irregular, found in diffusion boundaries. Cuboidal epithelium is cube-like, involved in secretion and absorption. Columnar epithelium is column-like, also involved in secretion and absorption. Ciliated epithelium has cilia for moving particles. Glandular epithelium is specialized for secretion.
Epithelial Tissue: Compound Epithelium and Cell Junctions [3:50:37]
The instructor explains that compound epithelium has multiple layers and provides protection against mechanical and chemical stresses. It is found in the dry surface of the skin, buccal cavity, and ducts of salivary glands. She also discusses cell junctions: tight junctions (prevent leakage), adhering junctions (cement neighboring cells together), and gap junctions (facilitate communication between cells).
Glands: Types and Modes of Secretion [3:53:54]
The instructor details the types of glands: unicellular (e.g., goblet cells) and multicellular (e.g., salivary glands). She also discusses modes of secretion: exocrine glands (with ducts, secreting mucus, saliva, earwax, oil, digestive enzymes) and endocrine glands (ductless, secreting hormones directly into the bloodstream).
Connective Tissue: Components and Types [3:55:45]
The instructor introduces connective tissue, the most abundant and widely distributed tissue. Components include the matrix or ground substance, cells (fibroblasts, macrophages, adipocytes), and fibers. Specialized connective tissues include skeletal (bone and cartilage) and fluid (blood).
Connective Tissue: Skeletal and Fluid Types [3:58:36]
The instructor compares skeletal connective tissues (bone and cartilage). Cartilage has a pliable matrix with chondrocytes, found in the tip of the nose, outer ear, and between vertebrae. Bone has a hard matrix with osteocytes, providing the main structural framework. Fluid connective tissue (blood) is composed of plasma, RBCs, WBCs, and platelets.
Connective Tissue: Loose and Dense Types [4:02:49]
The instructor discusses loose connective tissues: areolar tissue (with fibroblasts, providing support for epithelial tissue) and adipose tissue (with adipocytes, storing fat). Dense connective tissues include dense regular (parallel bundles of collagen fibers, found in tendons and ligaments) and dense irregular (irregularly arranged fibers, found in the skin).
Muscular Tissue: Types and Characteristics [4:04:37]
The instructor introduces muscular tissue, composed of muscle fibers and myofibrils. The three types of muscles are skeletal (striated, voluntary), smooth (non-striated, involuntary), and cardiac (striated, involuntary). She compares their characteristics, including shape, number of nuclei, location, striations, branching, and control.
Muscular Tissue: Structure and Contraction [4:06:10]
The instructor details the structure of striated muscle, including myofibrils, Z lines, sarcomeres, and thick and thin filaments. Thin filaments contain actin, troponin, and tropomyosin, while thick filaments contain myosin. Muscle contraction occurs when myosin binds to actin, forming cross-bridges and sliding the filaments past each other.
Muscle Contraction Mechanism [5:28:16]
The instructor explains the mechanism of muscle contraction, where calcium ions released from the sarcoplasmic reticulum bind to troponin, causing tropomyosin to move and expose the actin-binding sites. Myosin then binds to actin, forming cross-bridges and initiating contraction.
Skeletal System: Overview and Components [5:31:24]
The instructor introduces the skeletal system, composed of 206 bones and cartilage. Bones have a hard matrix due to calcium salts, while cartilage has a pliable matrix due to chondroitin salts. The skeletal system is divided into the axial skeleton (80 bones) and the appendicular skeleton (126 bones).
Axial Skeleton: Skull and Vertebral Column [5:35:17]
The instructor details the bones of the axial skeleton, including the skull (22 bones), hyoid bone (1), and ear ossicles (6). The skull is composed of cranial bones (frontal, parietal, temporal, occipital, sphenoid, ethmoid) and facial bones (nasal, maxilla, zygomatic, lacrimal, palatine, inferior nasal conchae, mandible, vomer). The vertebral column consists of cervical (7), thoracic (12), lumbar (5), sacral (1), and coccygeal (1) vertebrae.
Axial Skeleton: Sternum and Ribs [5:42:39]
The instructor explains that the sternum is a flat bone on the ventral midline. There are 12 pairs of ribs: true ribs (7 pairs, directly attached to the sternum), false ribs (3 pairs, indirectly attached), and floating ribs (2 pairs, not attached to the sternum).
Appendicular Skeleton: Limbs and Girdles [5:45:12]
The instructor details the bones of the appendicular skeleton. Each forelimb (arm) has 30 bones: humerus, radius, ulna, carpals (8), metacarpals (5), and phalanges (14). Each hindlimb (leg) also has 30 bones: femur, patella, tibia, fibula, tarsals (7), metatarsals (5), and phalanges (14). The pectoral girdle (shoulder) consists of the clavicle (collar bone) and scapula (shoulder blade). The pelvic girdle consists of two coxal bones (ilium, ischium, and pubis).
Joints: Types and Characteristics [5:51:54]
The instructor discusses the three types of joints: fibrous (immovable, e.g., sutures in the skull), cartilaginous (slightly movable, e.g., between vertebrae), and synovial (freely movable, e.g., knee). Synovial joints include ball-and-socket, hinge, pivot, gliding, and saddle joints.
