INTRODUCTION I. SYLLABUS & COURSE POLICIES II. BODY ORGANIZATION
A. Chemical Level: atoms and molecules
B. Cellular Level: Cell: basic structural and functional unit of life
C. Tissue Level: Tissue: similar cells that perform a common function
D. Organ Level: Organ: 2 or more kinds of tissues integrated to perform specific functions
E. Organ System Level: Organ system: organs having related functions
F. Organismal Level: Organism: has several organ systems which work together to maintain life
III. PLANES OF REFERENCE & DESCRIPTIVE TERMINOLOGY A. Anatomical Position: upright, feet parallel, eyes & palms forward
B. Planes of Reference: Imaginary lines or actual dissecting cuts (sections) which may be used to "section" the body or an organ.
1. Sagittal: divides the body or organ into unequal right and left portions.
a. Midsagittal: divides the body or organ into equal HALVES
2. Coronal (= Frontal) Plane: divides the body or organ into anterior (front) and posterior (back) portions
3. Transverse (= Horizontal, Cross-sectional) Plane: Divides the body or organ into superior (top) and inferior (bottom)
C. Directional Terms for the Body: Terms are in table 1.2 on p. 12, (and fig 1.7 on p. 13) - LEARN THEM!! Ex: Medial: closer to midline Lateral: away from the midline
IV. BODY REGIONS
A. Cephalic Region or Head
1. Facial Region a. Orbital – eye b. Nasal – nose c. Buccal –cheek d. Oral – mouth e. Mental –chin
2. Cranial Region –area covered by the scalp
B. Neck or Cervical Region (neck= cervix)
C. Thorax or Thoracic Region (chest)
1. Pectoral Regions –left and right chest
2. Mammary Regions (breasts) –sit atop pectoral regions
3. Sternal Region-between pectoral regions
4. Axillary Regions - armpits
D. Abdominopelvic Region
1. Abdominal Region - located below the diaphragm and the top of the hip bones
2. Pelvic Region –between the hip bones
E. Upper Extremity
1. Deltoid Region - shoulder
2. Brachial Region - arm; shoulder to elbow
3. Cubital (front = Antecubital) Region - elbow region
4. Antebrachial Region-forearm
5. Carpal Region - the "wrist"
6. Hand (Manus Region)
a. Palmar –front of hand
b. Dorsum –back of hand
F. Lower Extremity
1. Femoral Region –thigh
2. Knee:
a. Patellar (kneecap=patella) Region - front surface of knee
b. Popliteal Region – back of the knee
3. Crural Region - leg, from knee to ankle
4. Tarsal Region - ankle
5. Foot (Pedal Region)
a. Plantar -sole
b. Dorsum –top surface V. BODY CAVITIES
A. Dorsal (Posterior) Body Cavity
1. Cranial Cavity - brain resides here
2. Vertebral Cavity –spinal cord resides here
B. Ventral (Anterior) Body Cavity
1. Thoracic Cavity (chest cavity)
a. Pleural Cavities - a lung resides in each
b. Mediastinum - cavity between lungs
c. Pericardial Cavity (within mediastinum) contains the heart
2. Abdominopelvic Cavity
a. Abdominal Cavity – from thoracic diaphragm to top of hip bones
b. Pelvic Cavity –between hipbones
Which of the following refers to the region from the knee to the ankle?
a. Femoral
b. Crural
c. Patellar
d. Popliteal
e. Plantar
LECTURE 2: CELL
I. BASIC CELL COMPOSITION
A. Plasma membrane = Cell membrane –surrounds cell and gives it form
1. Structure: 2 layers of phospholipids (fats) with proteins scattered throughout
a. Proteins: In membrane or “float” on surface
b. Glycoproteins: proteins with carbohydrate (sugars) attached
2. It is selectively permeable. Determined primarily by size, charge, and solubility. Regulates movement of material in/out of cell.
3. Functions
a. Passive Transport (no energy)
i. Diffusion: Some SMALL materials may diffuse/pass through the cell membrane
b. Active Transport (energy required) LARGE particles must be transported actively: Two Types:
i. Exocytosis: process by which cellular materials EXIT the cell
-Materials are packaged within vesicles (small sacs)
- Vesicles fuse w/cell membrane and release contents outside of cell ii. Endocytosis: process by which materials are brought INTO the cell.
- Phagocytosis: “cell eating”; ingestion of large particles
- Pinocytosis: “cell drinking”; ingestion of fluid and small particles
4. Specializations of plasma membrane:
a. Microvilli: nonmotile, help increase surface area
b. Cilia: motile, move substances over the surface of stationary cells.
c. Flagellum: motile, whip like structure that moves cells-more contact with food, the better it is broken down and more is observed, only in sperm
B. Cytoplasmic Organelles
1. Mitochondrion
a. Makes ATP (adenosine triphosphate), energy molecule
2. Ribosomes - involved in protein synthesis (synthesis=production)
a. Two kinds:
Free ribosomes: makes proteins for the cell
Ribosomes attached to ER: make proteins for export
3. Endoplasmic Reticulum (ER) - a network of tubules used to transport & synthesize (produce) materials
a. Rough ER - has ribosomes on walls. Transports and modifies proteins made by ribosomes
b. Smooth ER:
-Synthesizes lipids, mainly steroids
-Detoxify drugs and alcohol
4. Golgi Apparatus: several C-shaped sacs near the nucleus
a. Packages material for secretion
b. Forms lysosomes
5. Lysosomes - contain digestive enzymes
a. Enzymatically breaks down internalized material and old organelles”garbage men” of the cell
6. Centrioles – needed for cell division
-Red blood cells and neurons don’t divide because they don’t have centrioles
C. Nucleus
1. Nuclear Envelope (Nuclear Membrane): It has nuclear pores and is selectively permeable
2. Nucleolus - contains proteins and RNA
3. Chromatin - coiled mass of DNA (1/2) wrapped around proteins (1/2)
II. DNA (= deoxyribonucleic acid) COMPOSITION/REPLICATION
A. It is made up of nucleotides (each consists of a phosphate group, sugar, and base)
B. Shape: double helix
C. Prior to cell division, the DNA "unzips"
1. Free nucleotides will attach to the two half-ladders, forming two identical DNA strands = replication Which of the following is responsible for protein production?
a. Mitochondrion
b. Lysosome
c. Smooth endoplasmic reticulum
d. Rough endoplasmic reticulum
e. Ribosome
LECTURE 3: CELL DIVISION I. CELL CYCLE
A. Cells are divided into two groups:
1. Sex cells (sperm and ova [eggs])
2. Somatic cells (all other cells)
B. Cell cycle subdivided into 2 phases:
1. Interphase - cell is not dividing
a. DNA is replicated during this time (S PHASE)
2. Mitosis (cell division for somatic cells) or Meiosis (cell division for sex cells) II. MITOSIS - Note: DNA was replicated during interphase
A. Prophase
1. Chromatin (1/2 DNA and ½ proteins) becomes supercoiled to form
Chromosomes
2. Chromosomes are double-stranded DNA. That is, 2 chromatids joined by a centromere.
a. Chromatid = one of the duplicated DNA strands
3. Spindle fibers extend from centrioles to the centromere
4. Nuclear membrane and nucleolus are dismantled
B. Metaphase (“Middle”)
1. Chromosomes align along center of cell
C. Anaphase
1. The two chromatids split apart at centromere
2. Each chromatid, a single strand of DNA, is pulled to opposite ends of cell
D. Telophase
1. Chromosomes uncoil
2. Nuclear envelope and nucleolus reforms
3. Cleavage furrow develops
Cytokinesis = division of cytoplasm (usually occurs) cells now enter interphase
Cytokinesis (not part of mitosis)= division of cytoplasm (usually occurs). Cells now enter interphase III. MEIOSIS
Definition: cell division where gametes (= sex cells: sperm cells or eggs) are formed
A. Differences between mitosis and meiosis:
1. Mitosis produces 2 cells containing 46 chromosomes. 23 pairs of a single stranded DNA
a. The two new cells are identical to original cell
2. Meiosis: produces 4 cells containing only 23 strands of DNA
B. Meiosis: Starts off with one cell that has 23 pairs of chromosomes.
-One set of chromosomes came from mother, the other set from the father
-During interphase: DNA gets replicated
-Cell now contains 23 pairs of double stranded chromosomes (total: 92 strands of DNA)
There are two consecutive meiotic divisions
1. Meiosis
a. Prophase I
i. The process of synapsis allows for the chromosomes line up in groups of four = tetrads ii. Crossover occurs: process by which genetic material is exchanged between sister chromatin
b. Metaphase I, Anaphase I, Telophase I: the cell finishes Meiosis I by separating the tetrads and producing 2 new cells
2. Meiosis II: Each of the 2 cells produced from Meiosis I divide (NO DNA REPLICATION BEFORE THIS DIVISION):
a. Prophase II, Metaphase II, Anaphase II (centromeres are separated and individual chromatids [single-stranded DNA] are pulled to opposite ends of the cell), Telophase II.
b. 4 cells (gametes) produced each with 23 single stranded DNA molecules
In which of the following stages of mitosis do the centromeres split and the chromatids begin to separate?
a. Prophase
b. Anaphase
c. Telophase
d. Metaphase
e. None of the above, this only happens in meiosis
Lecture 4: TISSUES I
I. CLASSIFICATION OF TISSUES
A. Histology: microscopic study of tissues
B. 4 kinds: Epithelia, Connective, Muscle, and Nervous II. EPITHELIA
A. Characteristics of Epithelia: covers body/organ surfaces, lines body cavities and forms glands
1. Very cellular
2. Has a free surface (apical surface) no other cells in contact with tissues (on one end)
3. Bound to underlying tissue by a basement membrane
4. Avascular- no blood vessels here (there are blood vessels below that diffuse necessities to keep epithelial alive) –diffusion=movement of molecules from a higher to a lower concentration how water, O2, and glucose get through the BM B. Classification
1. Classified by LAYERS:
a. Simple Epithelium—one layer thick
b. Stratified Epi. —Many layers thick (more than one layer)
2. Classified by cell SHAPE:
a. Squamous - flattened cells (plate like) (scales of snake skin)
b. Cuboidal – cube-shape cells
c. Columnar –rectangular shaped cells III. TYPES OF SIMPLE EPITHELIA
A. Simple Squamous Epithelium
1. One layer of flattened cells
2. Location: lines lumen (cavity) of blood vessels, tiny air sacs of lungs (alveoli), covers organs, and lines body cavities
3. Function: rapid diffusion and filtration B. Simple Cuboidal Epitheliumsometimes called glandular epithelium
1. One layer of cube-shaped cells
2. Location: lines ducts and tubules (e.g., salivary glands and kidneys)
3. Function: secretion and absorption
C. Simple Columnar Epithelium
1. One layer of tall, rectangular-shaped cells. May have microvilli, goblet cells, or cilia.
2. Location: lines ducts and tubules most of GI (gastrointestinal tract) i.e. Salivary glands and kidneys
3. Function: secretion (of enzymes) and absorption (of nutrients)—goblet cells bulbous and create mucus
D. Pseudostratified Columnar Epithelium
1. One layer of columnar or irregularly shaped (tall and short) cells. Some kinds have cilia (pseudostratified CILIATED columnar epithelium) and goblet cells
2. Location: lines trachea and bronchi (respiratory system)
3. Function: protection and secretion (mucus)
-pseudostratifiedall cells in contact with the basement membrane, nuclei at different levels in cells but are just singular elongated cells
-cilia move mucus that has caught dirt/dust particles up and out towards the mouth and away from the inside of the body
-smoking inhibits the effects of the cilia, smokers cough is to hack up mucus forcefully to overcome the lack of cilia function IV. TYPES OF STRATIFIED EPITHELIA
A. Stratified Squamous Epithelium: Upper layers of cells are flattened, lower layers appear cuboidal. Deepest layers highly mitotic. Two kinds:
1. Keratinized: contains keratin, superficial layers consist of dead cells
a. Location: epidermis
b. Function: protection (creates a barrier against environment, also keeps in nutrients), may look cuboidal or columnar, active and highly meitotic, “cornified”hard and brittle skin
2. Nonkeratinized: superficial cells are alive and kept moist (by fluid)—not on surface of body, keratin is unnecessary
a. Location: oral cavity, pharynx, vagina, and the lower part of the anal canal
b. Function: protection (barrier due to thickness instead of keratin)
B. Transitional Epithelium: some cells are binucleated. Surface cells may be dome-shaped or flattened.
a. Location: found in most of the urinary tract
b. Function: withstands distention (stretching) and relaxing—some dome shaped or scalloped on the free surface
V. GLANDULAR EPITHELIA: Specialized epithelial tissues that have excretory functions
A. Exocrine Glands formed from epithelial tissues - they secrete their materials onto a free surface
1. Unicellular: Goblet cells.
a. Location: Respiratory and Digestive systems
b. Function: secrete mucus
2. Multicellular: secrete materials through a duct to a free surface
a. Merocrine glands: secretes watery fluid through the cell membrane (example: salivary glands)
b. Apocrine glands: top part of the cell is pinched off, it becomes the secretion. Example - mammary glands
c. Holocrine glands: entire cell is released; it ruptures and dies (example: sebaceous [oil] gland) Which of the following epithelial tissues allows for rapid filtration and diffusion?
a. Simple squamous
b. Simple columnar
c. Transitional
d. Simple cuboidal
e. Nonkeratinized stratified squamous
Lecture 5: TISSUES II I. CHARACTERISTICS OF CONNECTIVE TISSUES: binds/supports/ protects other tissues and organs, derived from mesenchyme (embryonic CT)
A. Consists of:
1. Cells: the cells don’t have a free surface
2. Matrix = the non-living material surrounding the cells. It contains:
a. Fibers (protein)
i. Collagenthe more collagen, the stronger the tissue ii. Elastinprovide CT with flexibility iii. Reticularsupport and strength, somewhat weak
b. Ground Substancesupports the fibers and combines with them to make up the matrix itself
3. Vascularity varies II. CLASSIFICATION OF C.T.
A. Connective Tissue Proper: nonliving Matrix is gel-like; Two classes: Loose CT and Dense CT
1. Loose CT
a. Areolar CT
i. Contains fibroblasts, many irregularly arranged fibers and it is very vascular ii. Location: surrounds nerves, muscles, and some organs iii. Function: packing & binding material
b. Adipose (Fat Tissue)
i. Contains adipocytes: cells that store fat ii. Location: primarily in the skin iii. Functions: energy source; insulation against temperature changes, and protection (shock absorber)
2. Dense CT
a. Dense Irregular CT
i. Contains fibroblasts; protein fibers (dense) found are irregularly arranged bundles ii. Location: skin, dermis iii. Function: strength and support (in all directions)
b. Dense Regular CT
i. Contains fibroblasts; protein fibers are arranged in parallel bundles. Poor vascularity ii. Location: tendons and ligaments iii. Function: Strength and support (in one direction)
B. Cartilage: semisolid matrix; avascular; flexible; heals slowly; cells = chondroblasts and chondrocytes; cells in lacunae.
1. Hyaline Cartilage:
a. Matrix contains very fine collagen fibers
b. Location: found on articular surfaces, nasal septum, trachea, fetal skeleton
c. Function: support and protection
2. Fibrocartilage
a. Matrix contains thick collagen fibers.
b. Location: found in intervertebral disks, symphysis pubis & menisci
c. Function: support and withstands compression
3. Elastic Cartilage
a. Matrix contains numerous elastic fibers
b. Location: outer ear and larynx (voice box)
c. Function: flexibility and strength
C. Bone (Osseous Connective Tissue): matrix is rigid
1. 3 kinds of cells found in bone:
a. Osteoblasts –immature bone cells: create bone
b. Osteocytes –mature bone cells: maintain bone
c. Osteoclasts –break down/reabsorb bone
2. Two kinds of bone tissue found within each of your bones:
a. Compact (dense): outer shell of bone
b. Spongy (cancellous): inner latticework of bone; hemopoietic (red bone marrow) tissue found within spaces
D. Vascular Tissue (Blood)
1. Contains blood cells (or formed elements) and a liquid matrix called plasma
2. Function: transport III. MUSCLE TISSUE: moves body and materials within body
A. Classification
1. Smooth (Visceral) Muscle Tissue found in (walls of all hollow organs except for the heart)
a. Spindle-shaped cells
b. One centrally located nucleus
2. Cardiac Muscle Tissue
a. Short, cylindrical cells
b. Some cells are bifurcated (branching)
c. Has one or TWO centrally-located nuclei located nuclei
d. Intercalated discs: mass of proteins that holds two cells together
e. Striations
3. Skeletal Muscle Tissue
a. Long, cylindrical cells
b. Multinucleated
c. Nuclei located at periphery of cell
d. Striations IV. NERVOUS TISSUE: makes up the nervous system
A. Classification
1. Neurons
a. Generate and conduct nerve impulses
2. Supporting Cells (Neuroglia)
b. Support, protect and nourish neurons Which of the following is found in the outer ear and larynx and functions to provide flexibility and strength?
a. Dense regular connective tissue
b. Areolar connective tissue
c. Fibrocartilage
d. Elastic cartilage
e. Dense irregular connective tissue
Lecture 6: INTEGUMENTARY SYSTEM I. Introduction
A. Integument =covering=skin (largest organ of the body)
B. Integumentary system = Skin + Exocrine glands + Hair + Nails + associated nerves + associated blood vessels II. Layers of the Integument
A. Epidermis: (epi=on, derma=skin)
1. Outer layer
2. Composed of keratinized stratified squamous epithelium
3. Avascular
4. Thick skin = 5 layers Thin skin = 4 layers B. Dermis
1. Middle layer
2. Composed primarily of dense irregular connective tissue
3. Contains nerve endings, hair follicles, & glands
4. Dermal papillae (projections of the dermis into the epidermis)
C. Subcutaneous layer (= hypodermis; superficial fascia)
1. Deepest layer
2. Stores fat and anchors upper layers to other tissues
3. Composed of areolar CT and adipose CT
III. Layers of Epidermis
A. Stratum Basale: single layer of columnar/cuboidal cells resting on the basement membrane; cells are very mitotic
B. Stratum Spinosum: several layers of polygonal-shaped cells with spines. Small degree of mitosis here
C. Stratum Granulosum: 3-5 layers of flattened cells with visible granules; cells undergo keratinization here (keratinization = the process by which the nucleus shrivels up, cell dies, and cell fills up with the protein keratin)
D. Stratum Lucidum: 2-3 layers of dead, anucleated, keratinized, clear cells; only found in thick skin
E. Stratum Corneum: 20-30 layers of dead, keratinized, anucleated cells (cornified = brittle, hardened); outer cells are constantly shed IV. Cells of the Epidermis
1. Keratinocytes: most numerous (90%); found in all layers; produce keratin
2. Melanocytes: 2nd most numerous (8%); found only in the stratum basale; produce melanin (protects us from UV light)
3. Tactile (Merkel) Cells: 3rd most numerous (1%); found only in the stratum basale; provide information regarding tactile (light touch) sensation
4. Epidermal dendritic (Langerhans) cells: 4th most numerous (<1%); found primarily in the stratum spinosum; phagocyte
V. Layers of the Dermis
A. Papillary Layer: uppermost; composed of dermal papillae; contains blood vessels; sensory receptors (neurons); portions of the ducts of glands and hair roots
B. Reticular Layer: deepest; contains blood vessels; sensory receptors (neurons); secretory portions of glands; hair follicles; ducts of glands VI. Epidermal Derivatives (Skin Appendages)
A. Hair:
1. 3 parts: bulb, root, and shaft
2. Arrector pili muscle
3. Function: protects from UV light, trauma, and heat loss
B. Nails:
1. Formed from stratum corneum
2. Function: protection and grasping
C. Exocrine glands: 3 kinds
1. Sebaceous glands = Oil (= sebum) glands
a. Associated with hair follicles
b. Functions: soften the skin & bactericidal
2. Sweat (sudoriferous) glands a. Eccrine
i. Found everywhere ii. Releases perspiration (sweat)
b. Apocrine
i. Axillary and pubic regions ii. Secretes onto hair shafts iii. Releases an odiferous secretion
3. Ceruminous (cerumen = earwax)
a. Modified sweat glands
b. In external auditory canal
c. Cerumen is an insect repellant and helps keep the
Eardrum “soft”
Which of the following cells is found only in the stratum basale and is a light touch receptor?
a. Keratinocyte
b. Fibrocyte
c. Epidermal dendritic (Langerhans) cell
d. Tactile (Merkel) cell
e. Melanocyte
BONE I I. INTRODUCTION
A. Osteology: the study of bones
B. Bones are organs
C. Adult skeleton: 206 bones
1. Skeleton subdivided into:
a. Axial skeleton –bones of head, neck and trunk b. Appendicular skeleton –bones of upper and lower extremities II. GROSS ANATOMY OF BONES
A. Bone Shape
1. Long Bones
a. longer than they are wide
2. Short Bones
a. approximately as long as they are wide
3. Flat Bones
a. Relatively thin, have broad surface
4. Irregular Bones
a. have irregular and varied shapes
B. Gross Anatomy of a Long Bone
1. Diaphysis - cylindrical shaft
2. Medullary Cavity - hollow inside of diaphysis
a. lined with endosteum
b. contains yellow bone marrow (adipose)
3. Epiphysis (plural: epiphyses) - ends of the bone
a. outside layer of compact bone surrounding spongy bone
b. in the spaces of the spongy bone = red bone marrow (hemopoietic tissue)—for blood cell production
4. Articular Cartilage - hyaline cartilage on the epiphyses
a. helps joints move easily
5. Epiphyseal Plate - hyaline cartilage plate between diaphysis and epiphysis
a. Function: lengthwise bone growth
6. Periosteum - dense irregular connective tissue that covers outside of bone
a. exception: periosteum not found on articular surfaces of bone
b. Sharpey's fibers (perforating fibers)
c. there are cells (osteoblasts) associated with the periosteum which are responsible for bone width growth III. BONE HISTOLOGY
A. 3 kinds of cells:
1. Osteoblasts: create bone
2. Osteocytes: maintain bone matrix
3. Osteoclasts: break down/reabsorb bone
B. Compact bone: Made up of osteons = Haversian Systems
1. Osteons (Haversian Systems) consist of:
a. Central Canal (Haversian Canal): opening that runs parallel to length of diaphysis; contains blood vessels/nerves
2. Lamellae: concentric rings of bone matrix
3. Osteocytes: mature bone cells
4. Lacunae: spaces where osteocytes reside
5. Canaliculi: tiny channels that radiate from lacunae. Contain cytoplasmic projections of osteocytes for diffusion of nutrients
6. Perforating (Volkmann's) Canals: canals that run perpendicular to the central canals; connect central canals
7. Interstitial Lamellae (Interstitial Systems): incomplete remnants of osteons
8. Circumferential Lamellae: rings of bone that run the entire circumference of the shaft; made by cells of periosteum. All of the following are part of a Haversian (osteon) system EXCEPT:
a. Lamellae
b. Canaliculi
c. Haversian canal
d. Lacunae
e. Periosteum
BONE II I. OSSIFICATION (OSTEOGENESIS): the process of bone tissue formation; 2 types:
A. INTRAMEMBRANOUS OSSIFICATION: preexisting tissue is mesenchyme. Used to form primarily flat bones
1. Mesenchymal cells differentiate into osteoblasts
2. Woven bone and surrounding periosteum form
3. Compact bone and spongy bone replace woven bone
B. ENDOCHONDRAL OSSIFICATION: preexisting tissue is a hyaline cartilage model surrounded by perichondrium. Used to form long bones. 1. First, the perichondrium is invaded by blood vessels
a. Cells in perichondrium turn into osteoblasts
b. Perichondrium transformed into periosteum
2. Osteoblasts secrete osteoid onto cartilage
a. forms bone collar (periosteal bone collar)
3. Due to the penetrating periosteal bud (blood vessels), chondrocytes enlarge w/in shaft
a. cartilage undergoes calcification
b. chondrocytes die
4. Along with the penetrating periosteal bud (blood vessels), osteoblasts and osteoclasts penetrate inside
a.
5. Processes 3. & 4. are repeated at the ends (epiphyses) of the bone
a. secondary ossification centers
6. Cartilage removed, except at articular surfaces of bone and ends of diaphysis
a. cartilage plate between epiphyses and diaphysis = epiphyseal plate b.
c.
7. As bone develops, new bone is being laid down by osteoblasts
a. osteoclasts remove bone from inside of diaphysis, creating medullary cavity
APPOSITIONAL BONE GROWTH: Process of bone formation and removal = bone remodeling - Occurs throughout a person’s life - Production = removal II. BONE FRACTURES
A. Kinds of fractures:
1. Simple (closed):
2. Compound (open): bone breaks through skin
3. Comminuted:
4. Compression: bone is crushed
5. Depressed:
6. Impacted: broken bone ends are forced into each other
7. Spiral:
8. Greenstick: bone breaks incompletely B. Fracture Repair:
1. When bone breaks, a fracture hematoma forms
2.
3. Soft callus replaced with a bony (hard) callus:
4. The newly repaired bone is remodeled: All of the following are part of endochondral bone formation EXCEPT:
a. Perichondrium invaded by blood vessels
b. A bony callus forms
c. Cartilage undergoes calcification
d. Medullary cavity is formed
e. Chondrocytes die
