Anatomical Terminology and Planes

Anatomical Terminology

• Medial: Closer to the midline.
• Lateral: Further from the midline.
• Proximal: Closer to the attachment point or torso.
• Distal: Further from the attachment point or torso.
• Superior: Above.
• Inferior: Below.
• Anterior: Frontside.
• Posterior: Backside.
• Ventral: Bellyside.
• Dorsal: Backside.
• Cranial: Closer to the cranium.
• Caudel: Closer to the tail.
• Ipsilateral: On the same side.
• Contralateral: On opposing sides.
• Superficial: Closer to the surface.
• Deep: Further from the surface.

Planes

• Coronal/Frontal: Separates the body into anterior and posterior portions.
• Transverse: Separates the body into superior and inferior portions.
• Sagittal: Separates the body into left and right portions.
• Midsagittal: Separates the body into equal left and right portions.
• Mid-Axillary: Separates the body into anterior and posterior portions from the midline of the armpit.
• Mid-Clavicular: Separates the body into left and right portions from the midline of the collarbone.

Cavities

• Cranial: Contains the brain and skull.
• Thoracic: Contains the lungs and heart.
• Vertebral: Contains the vertebral column (spine).
• Pericardial: Contains the heart.
• Pleural: Contains the lungs.
• Abdominal: Contains the liver, stomach, intestines, spleen, pancreas, gallbladder, etc.
• Pelvic: Contains the pelvis.

Skeleton

• Appendicular: Contains the pectoral girdle, pelvic girdle, upper limbs & lower limbs
• Axial: Contains the skull, vertebral column, & thoracic cage

Bones

• There are 206 bones in total.
• Skull has 22 bones including the vomer, temporal, occipital, frontal, nasala, maxilla, mandible, lacryimal, zygomatic, spehnoid, ethmoid and parietal.
• Pectoral Girdle has 4 bones including the clavicle, scapula.
• Pelvic Girdle has 5 bones including the illium, ischium, pubis.
• Thoracic Cage has 25 bones including the ribs, sternum.
• Upper Limbs has 30 bones including the humerus, radius, ulna, carpals, metacarpals, proximal phalanges, middle phalanges and distal phalanges.
• Lower Limbs has 30 bones including the femur, tibia, fibula, patella, talus, calcaneus, tarsals, metatarsals, proximal phalanges, middle phalanges and distal phalanges.
• Vertebral Column has 33 bones including the cervical (C7), thoracic (T12/D12), lumbar (L5), sacral (S5) and coccygeal (Co4).

Body Systems

• Integumentary: Protects, regulates temperature, and provides sensory information.
• Musculoskeletal: Provides structure, movement, protection, and support.
• Lymphatic: Filters/drains harmful substances and maintains fluid balance.
• Nervous: Communication network through CNS & PNS.
• Respiratory: Exchanges oxygen with carbon dioxide.
• Cardiovascular: Transports oxygen & nutrients while removing waste products.
• Gastrointestinal: Breaks down food, extracts nutrients, & filters out waste products.
• Reproductive: Enables the production of offspring.
• Endocrine: Regulates metabolic processes through the secretion of hormones.
• Immune: Protects from foreign substances.
• Urinary: Filters waste products from the blood to maintain fluid balance.

Histology

• Histology is the study of tissues.
• The organization of the body goes from organism, to organ system, to organ, to tissues, to cells.

Tissue Types

• Epithelial tissues include squamous (simple), cuboidal, columnar, pseudostratified, and stratified (simple), cuboidal, columnar, transitional.
• Connective tissues include adipose, blood, bone, cartilage (elastic, hyaline, fibrocartilage), dense tissue (regular, irregular), and loose tissue (areolar, reticular).
• Muscular tissues include skeletal, cardiac, and smooth.
• The fourth type of tissue is nervous tissue.

Cell Structure and Transport

• Cell shapes include squamous for diffusion, cuboidal for absorption and secretion, and columnar for absorption in respiratory and digestive tracts.
• Additional cell shapes include polygonal, spheroid, discoid, stellate, fibrous, and fusiform.
• Cell types include skin, muscle, stem, sex, neurons, adipocytes, erythrocytes, leukocytes, thrombocytes, osteocytes, osteoblasts, and osteoclasts.
• Phospholipid Bilayer: A double layer where hydrophilic heads face out and hydrophobic tails face inwards, creating a barrier for charged or hydrophilic molecules.
• The organelles are nucleus, nucleolus, nuclear membrane, ribosome, centrosome, lysosome, peroxisome, rough endoplasmic reticulum, smooth endoplasmic reticulum, Golgi apparatus, vacuoles, mitochondrion, cytoplasm, and cell membrane.
• Active transport requires energy to move substances against a concentration gradient, from low to high concentration.
• Passive transport does not require energy and moves substances down a concentration gradient, from high to low concentration.
• Diffusion is passive transport, where molecules move "down the hill".
• Osmosis is passive transport, where only water moves "down the hill".
• Facilitated diffusion: Requires a transport protein to move molecules "down the hill".
• Endocytosis: Cells engulf material (pinocytosis for liquids, phagocytosis for solids).
• Exocytosis: Cells remove material via vesicles.
• Both endocytosis and exocytosis are forms of active transport.
• Hypertonic solutions: Have more solutes/less solvent outside the cell, causing the cell to gain solvent and swell.
• Hypotonic solutions: Have less solutes/more solvent outside the cell, causing the cell to lose solvent and shrink.
• Isotonic solutions: Have equal solute/solvent concentrations, resulting in no change in cell volume.
• Prokaryotic cells (bacteria) are simple cells that lack a nucleus & membrane-bound organelles.
• Eukaryotic cells (plant, animal, fungi, algae, protozoa) are complex cells that possesses both a nucleus and membrane-bound organelles.

Mitosis

• G0: Cell is in a resting state.
• Interphase:
  • G1: Cell grows and prepares for DNA replication.
  • S: DNA replicates.
  • G2: Cell develops further and prepares for cell division.
• M (Mitosis):
  • Prophase: Chromosomes condense, nuclear envelope breaks down.
  • Metaphase: Chromosomes align at the center, attached to the mitotic spindle.
  • Anaphase: Sister chromatids are pulled apart to opposing poles.
  • Telophase: Chromatids decondense, nuclear envelope reforms, cell divides into two.

DNA & RNA

• DNA (Deoxyribonucleic Acid): Determines inherited characteristics, controls enzyme production, controls metabolism, and directs protein synthesis; contains thymine.
• RNA (Ribonucleic Acid): Controls intermediate steps in protein synthesis; contains uracil.
• Both DNA & RNA are made of strings of nucleotides which contain a pentose sugar (deoxyribose or ribose), a phosphate group, and a nitrogenous base (adenine, cytosine, guanine, thymine, or uracil.
• DNA: Double-stranded, held together by two strands of bases held together by hydrogen bonds (A bonds to T, C bonds to G).
• RNA: U bonds to A.

Proteins, Carbohydrates, & Fats (Macronutrients)

• Proteins: Monomers are amino acids with a central carbon atom, hydrogen atom, amino group, carboxyl group, & a variable side chain or R group; held by peptide bonds formed through a dehydration synthesis reaction.
• Proteins: Can take one of four shapes:
  • Primary Structure: Amino acids along a polypeptide chain.
  • Secondary Structure: Hydrogen bonds turn this into a spiral or pleated sheet.
  • Tertiary Structure: This coils & folds into a unique shape.
  • Quaternary Structure: Several of these put together to form one big shape.
• Enzymes: Proteins that serve as catalysts, reducing the activation energy required for reactions.
• Carbohydrates: Also known as saccharides (sugar); monomers are mono, di, or poly molecules.
• Polysaccharides/Complex Carbs/Complex Sugars: Bigger; take longer to be broken down.
• Mono/Disaccharides/Simple Carbs/Simple Sugars: Smaller; take shorter time to be broken down.
• Glucose not used is turned into glycogen & stored in both fat cells & the liver for later use.
• If the body has exhausted immediate energy sources (simple & complex carbs), it accesses this reserve of energy & turns it back into glucose for use (this is known as ketosis).
• Fats: Hydrophobic compounds whose monomers are lipids, containing fatty acids, eicosanoids, glycerides, steroids, phospholipids, and glycolipids.
• Fatty Acids are either saturated (single covalent bonds only) or unsaturated (one or more double covalent bonds).

Energy

• Both glucose and ATP molecules contain energy, however, we can compare it to currency (dollars and quarters respectively).
• Glucose gets broken down into adenosine triphosphate, which releases energy when it gets broken down further, or broken down into adenosine diphosphate and adenosine monophosphate.

Chemistry Refresher

• Organic Compounds: Contain carbon atoms, carbon-hydrogen bonds, covalent bonds, and are complex in nature (fats, nucleic acids, proteins, enzymes, etc.).
• Inorganic Compounds: Don't typically contain carbon atoms, contain carbon-hydrogen bonds, form ionic bonds and are simple in nature (salts, metals, acids, bases, etc.).

The Potential of Hydrogen (pH)

• pH: Represents the potential of hydrogen & is a scale representing the acidity or basicity of an aqueous solution.
• The higher amount (-) hydroxyl ions means the solution is more acidic.

Chemical Reactions

• Synthesis: A + B > AB.
• Decomposition: AB > A + B.
• Combustion: AB + Oxygen > A-Oxygen + B-Oxygen.
• Replacement: (Single) AB + C > AC + B, (Double) AC + BD > AD + BC.
• Reversible: AB ⇌ CD.

Chemical Bonds

• Ionic: Metal cation is attracted to a nonmetal anion.
• Covalent: Two nonmetals share valence electrons.
• Hydrogen: A bond between hydrogen & an electronegative atom.
• Polar Covalent: Two nonmetals share electrons unequally.
• Nonpolar Covalent: Two metals share electrons equally.

Elements of the Human Body

• O (65%): Component of water & essential for respiration.
• C (18.6%): Found in all organic molecules.
• H (9.7%): A component of water & other bodily components.
• N (3.2%): Found in proteins, nucleic acids, & other organic compounds.
• Ca (1.8%): Found in bones, teeth, & crucial for muscle contraction and nerves.
• P (1.0%): Found in bones, teeth, nucleic acids, & high-energy compounds.
• K (0.4%): Crucial for membrane function, muscle contraction, & nerve impulse.
• Na (0.2%): Crucial for blood volume, membrane function, & nerve impulse.
• Cl (0.2%): Crucial for blood volume, membrane function, & water absorption.
• Mg (0.06%): A cofactor for enzymes.
• S (0.04%): Found in proteins.
• Fe (0.007%): Crucial for oxygen transport & energy capture.
• I (0.0002%): A component of thyroid gland hormones.