Lectures 1-15 Flashcards
What is the general process of sampling?
Sampling involves selecting a subset of individuals from a population to represent the whole population.
What is the difference between a population and a sample?
A population includes all individuals of interest, while a sample is a subset of the population used for study.
Why do we take samples in statistics?
Samples are taken to make inferences about the entire population without having to study everyone.
What is the difference between location (central tendency) and spread in statistics?
Location (central tendency) measures where the data centers (e.g., mean, median), while spread measures the variability or dispersion of the data (e.g., range, standard deviation).
Why are statistics important in health sciences?
Statistics help understand the health of the population, including the prevalence of diseases, risk factors, and the effectiveness of treatments.
How is the mean calculated?
The mean is calculated by dividing the sum of all values by the total number of observations.
Where is the primary ossification center located, and what does it do?
In the diaphysis (shaft); it develops bone at different times.
Where are the secondary ossification centers located, and what is their function?
In the epiphyses; they enable bone growth in length through the epiphyseal/growth plate.
How does bone grow in width?
Through appositional growth; osteoblasts add bone matrix to the surface, and osteoclasts remove bone matrix from the inside.
What are the key soft tissues involved in joint movement?
Cartilage (hyaline and fibrocartilage) and DFCT (ligaments, tendons, and joint capsules).
What is the function of hyaline cartilage?
To resist compression, mold bone surfaces at joints, and enable frictionless movement.
What is the function of fibrocartilage?
To resist tension and compression, act as a shock absorber, and deepen articular surfaces.
Describe the three types of joints.
Fibrous (least movement, provides stability), Cartilaginous (some movement, connected by fibrocartilage), and Synovial (most movement, made of various tissues).
What is the function of fibrous joints?
To limit movement and provide stability, found in sutures of the skull and distal tibiofibular joint.
What is the function of cartilaginous joints?
To allow some movement, found in intervertebral discs and pubic symphysis.
What is the function of synovial joints?
To allow a lot of movement, found in most appendicular skeleton joints.
What is DFCT, and what are its characteristics?
Dense Fibrous Connective Tissue; contains fibroblasts, collagen, and some elastin, resists tension, and has little vascularity.
What is the function of ligaments?
To connect bone to bone, resist tension, and restrict movement away from themselves.
What is the function of tendons?
To connect muscle to bone, facilitate and control movement, and transmit muscle contraction to bone.
What is bony congruence?
The sum of bone surfaces that form an articulation, requiring more soft tissue where there is less congruence.
Define tissue and structure.
Tissue: Cells grouped together in an organized manner (e.g., DFCT). Structure: Something formed of a tissue (e.g., ligament).
Describe the general principles of bone growth.
Bone grows in length at epiphyseal plates and in width through appositional growth involving osteoblasts and osteoclasts.
Describe the microanatomy of tissues in joints.
Hyaline cartilage resists compression; fibrocartilage resists tension and compression; DFCT resists tension.
Describe fibrous joints.
Made of DFCT, limit movement, provide stability (e.g., skull sutures).
Describe cartilaginous joints.
Made of fibrocartilage, allow some movement (e.g., intervertebral discs, pubic symphysis).
What is the function of bone cells?
They respond to external forces, change shape, remodel, and repair themselves.
What are the two extracellular components of bone?
Organic (33%) and inorganic (67%).
What makes up the organic component of bone?
Collagen and ground substance (proteoglycans); it resists tension.
What makes up the inorganic component of bone?
Hydroxyapatite and other calcium minerals; it makes bone hard and resistant to compression.
What percentage of a bone’s weight is cellular, and what are the types of cells involved?
2%; includes Osteogenic cells, Osteoblasts, Osteocytes, and Osteoclasts.
What is the role of Osteogenic cells?
They are stem cells that produce osteoblasts.
What is the role of Osteoblasts?
They produce new bone matrix.
What is the role of Osteocytes?
They recycle protein and minerals from the matrix.
What is the role of Osteoclasts?
They remove bone matrix.
What is the difference in structure between compact and cancellous bone?
Compact bone has an osteon structure; cancellous bone has a trabecular structure.
Describe the structure of compact bone.
Dense outer surfaces (periosteum), visible foramina for blood supply, made up of osteons with circumferential lamellae.
Describe the structure of cancellous bone.
Contains trabeculae (struts of lamella bone), marrow in cavities, and osteocytes in lacunae or on the surface.
What is the function of trabeculae in cancellous bone?
Resist force from multiple directions and spread force distally.
What is an osteon, and what is its function?
A lengthwise unit in compact bone; provides a pathway for nutrients to cells in the ECM.
What are the components of an osteon?
Central canal (with blood vessels and nerves), lamellae (cylinders of ECM), lacunae (for osteocytes), and canaliculi (channels for osteocytes).
How is bone homeostasis maintained?
Balance between Osteoblast and Osteoclast activity, allowing constant bone formation and destruction.
What happens during bone remodelling?
Osteoblasts add bone matrix to the surface, and osteoclasts remove bone from the medullary cavity.
What is required to maintain bone homeostasis?
Adequate dietary calcium and moderate exercise.
What causes Osteoporosis?
More Osteoclast activity than Osteoblast activity, leading to a loss of cortical bone and thinning of trabeculae.
Who is more likely to develop Osteoporosis and why?
Biological females, especially postmenopausal, due to a loss of oestrogen and lifestyle factors (lack of exercise, poor nutrition, alcohol, smoking).
Describe the microscopic structure of bones.
Compact bone has osteons with central canals, lamellae, lacunae, and canaliculi; cancellous bone has trabeculae with marrow and osteocytes.
How does bone maintain homeostasis?
By balancing Osteoblast and Osteoclast activity to regulate bone formation and destruction.
Describe a bone pathology related to lack of homeostasis.
Osteoporosis, caused by more Osteoclast activity than Osteoblast activity, leading to thinning trabeculae and increased fracture risk.
What percentage of tissue in the human body is epithelial tissue?
3%
What are the functions of epithelial tissue?
Covers exposed surfaces, lines internal passageways and chambers, forms secretory glands, provides physical protection, controls permeability, provides sensation, and produces specialized secretions.
What structures are included in epithelial tissue?
Epithelia and glands (exocrine and endocrine).
What percentage of tissue in the human body is connective tissue?
45%
What are the functions of connective tissue?
Fills internal spaces, provides structural support, stores energy, establishes a structural framework for the body, transports fluids and dissolved materials, protects delicate organs, supports, surrounds, and interconnects other types of tissues, stores energy (especially in the form of triglycerides), and defends the body from invading microorganisms.
What types of connective tissue are there?
Connective tissue proper (loose: areolar, adipose, reticular; dense: dense regular, dense irregular, elastic), fluid connective tissue (blood and lymph), and supporting connective tissues (cartilage: hyaline, elastic, fibrocartilage; bone).
What percentage of tissue in the human body is muscle tissue?
50%
What is the primary function of muscle tissue?
Contracts to produce movement.
What are the three types of muscle tissue?
Skeletal muscle, cardiac muscle, and smooth muscle.
What percentage of tissue in the human body is nervous tissue?
2%
What are the functions of nervous tissue?
Conducts electrical impulses and carries information.
How do atoms, molecules, cells, and tissues relate to each other?
Atoms combine to form molecules, which interact to form cells that can secrete and regulate. These cells and extracellular materials and fluids combine to form tissues.
Which tissue includes blood and lymph?
Connective tissue.
Which tissue forms glands?
Epithelial tissue.
Which tissue allows information to be quickly sent around the body?
Nervous tissue.
Which tissue can be divided into skeletal, cardiac, and smooth?
Muscle tissue.
Which tissue is the most common in the body?
Muscle tissue (50%).
Which tissue is the least common in the body?
Nervous tissue (2%).
Which tissues would you find in your knee joint?
Connective tissue (including cartilage and bone), muscle tissue, and nervous tissue.
Why is knowing terminology important in anatomy?
It allows effective communication and avoids vague descriptions or directions.
What is homeostasis?
It supports normal function of body systems by maintaining conditions in the internal environment through regulatory mechanisms.
What are some examples of set-points in homeostasis?
Temperature, ion concentrations (calcium, potassium, sodium), blood sugar levels, and fluid balance.
What is feedback in homeostasis?
When a controlled variable moves too far from the set point and the body responds to bring it back to normal.
What is feedforward in homeostasis?
Anticipation of an event that will alter a controlled variable, leading to actions that minimize the effect.
What responses are coordinated by the Heat-Loss centre when body temperature rises?
Behavioral changes, vasodilation, shunting of blood to the skin, sweat production, and respiratory heat loss.
What responses are coordinated by the Heat-Gain centre when body temperature lowers?
Behavioral changes, vasoconstriction, reduced sweat production, shivering, and goosebumps.
What is the correct anatomical position?
Upright, facing forwards, feet together, palms facing forwards.
What body parts are included in the upper limb?
Arm, forearm, and hand.
What body parts are included in the lower limb?
Thigh, leg, and foot.
What does the term “anterior” mean in anatomical terminology?
Towards the front of the body.
What does the term “posterior” mean in anatomical terminology?
Towards the back of the body.
What does the term “superior” mean in anatomical terminology?
Above or towards the head
What does the term “inferior” mean in anatomical terminology?
Below or towards the feet.
What does the term “medial” mean in anatomical terminology?
Closer to the midline of the body.
What does the term “lateral” mean in anatomical terminology?
Farther from the midline of the body.
What does the term “proximal” mean in anatomical terminology?
Closer to the point of attachment or origin.
What does the term “distal” mean in anatomical terminology?
Farther from the point of attachment or origin.
What does the term “superficial” mean in anatomical terminology?
Closer to the surface of the skin.
What does the term “deep” mean in anatomical terminology?
Farther from the surface of the skin.
What is the sagittal plane?
The plane that divides the body into left and right sections.
What is the coronal plane?
The plane that divides the body into front and back sections.
What is the transverse plane?
The plane that divides the body into top and bottom sections.
What are movements in the sagittal plane?
Flexion and extension.