HUBS 191
- The anatomy is the structure of an organ system, and the relationship between its
constituents.
- The physiology is the function of an organ system and its constituents.
Homeostasis:
- Homeostasis is the presence of a stable internal environment.
- Failure to maintain homeostasis soon leads to illness or even death
- Homeostasis is the central foundation of modern physiology.
- Homeostatic regulation is the adjustment of physiological systems to preserve
homeostasis in environments that are often inconsistent, unpredictable, and
potentially dangerous
- All homeostatic regulatory mechanisms consist of:
• A receptor which senses stimuli
• A control/integration centre which receives and processes the information
• An effector which responds to the stimulus
- Homeostatic control is not precise - it maintains a normal range, oscillating close
to a set point, rather than an absolute value
• Each individual will have their own normal range within which their levels of a
given variable fluctuate
• The population has a reference range based on the breadth of individual normal
ranges within a population. The population reference range tends to be wider
than normal fluctuations within an individual.
- Most individuals will have a set point within the population reference range
- In some cases, to maintain homeostasis, a change in set point (or reference range)
may be necessary, e.g:
• In a change in altitude, red blood cell count change is necessary to have a
sufficient oxygen carrying capacity
• In a shift to a location with a different climate, the BMR may be necessary to be
changed
• In a fever, the set point for the body’s temperature is temporarily changed.
- Basal metabolic rate (BMR) is the body’s rate of energy expenditure under basal
conditions, where the person is:
• Awake
• At physical and mental rest
• Lying down
• No muscle movement
• At a comfortable temperature
• Fasted for 12-18 hrs.
,Tissues:
- There exist trillions of cells in the human body, yet only about 200 different types
of cells.
- A tissue is a collection of similar cells and cell products that perform a limited
number of specialised functions.
- The study of tissues is known as histology.
- There exist four basic types of tissue: epithelial, connective, muscle and nervous
tissue.
Epithelial Tissue:
- Epithelial tissue consists of epithelia and glands, and it:
• Covers exposed surfaces
• Lines internal passageways and chambers
• Forms secretory glands.
- However, all cells of epithelial tissue share the property of polarity i.e they have
one apical and one basal end (with basolateral sides), both with different structural
and functional differences.
- Functions of epithelial tissue include:
• Provides physical protection from abrasion, dehydration and destruction by
chemical or biological agents.
• Controls permeability i.e selectively permeable.
• Provides sensation via nerves which extensively innervate most epithelia.
• Produce specialised secretions via gland cells in epithelia or glandular
epithelium.
Connective Tissue:
- Consists of cells dispersed in a matrix.
• The major component of the matrix is a ground substance, often crisscrossed by
protein fibers.
• i.e matrix = cells + ground substance + proteins
- Functions of connective tissue include:
• Fills internal spaces.
• Provides structural support.
• Stores energy.
• Protects delicate organs.
• Transports fluids and dissolved materials.
• Establishes a structural framework for the body.
• Defend body from invading microorganisms.
• Support, surround and interconnect other types of tissue.
- Connective tissue can be categorised into three sorts:
i). Connective Tissue Proper:
• Syrupy ground substance.
• Diverse types of cells.
• Can be dense or loose.
, • Dense connective tissue can be:
• Dense irregular
• Dense regular
• Elastic.
• Loose connective tissue proper can be:
• Areolar
• Adipose
• Reticular.
• Cell types can be sorted into fixed cells and wandering cells.
• Fixed cells include: melanocytes, fixed macrophages, mast cells, fibroblasts,
fibrocytes and adipocytes.
• Wandering cells include: Plasma cells, free macrophages, mesenchymal cells,
neutrophils, eosinophils, and lymphocytes.
• Fibers in connective tissue proper include:
• reticular fibers,
• collagen fibers,
• elastic fibers.
ii). Fluid Connective Tissue:
• Watery matrix with dissolved proteins.
• Distinctive cell populations.
• Either blood or lymph.
iii). Supporting Connective Tissue:
• Low cell diversity.
• Densely packed fibers in matrix.
• Protect soft tissues and support weight.
• Can be cartilage or bone.
Muscle Tissue:
- Contracts to produce movement.
- Includes:
• Skeletal muscle,
• Cardiac muscle,
• Smooth muscle.
Nervous Tissue:
- Conducts electrical impulses.
- Carries information.
- Nervous tissue consists of neurons and supporting cells called neuroglia, or glial
cells.
- Neurons:
• Have dendrites as branching appendages to the cell body which receive
information.
• Have an axon which conducts that information as electrical impulses to other
cells.
, • The cell body contains a large nucleus and a prominent nucleolus along with
various organelles.
- There exist several different types of neuroglia, each with specific functions.
General functions of neuroglia include:
• maintaining physical structure of nervous tissue,
• repairing nervous tissue framework after injury,
• performing phagocytosis,
• providing nutrients to neurons,
• regulating the composition of the interstitial fluid surrounding neurons.
- Overall in the human body,
• 50% of tissue is muscle tissue,
• 45% is connective tissue,
• 3% is epithelial tissue,
• 2% is nervous tissue.
- The male body consists of :
• 60% water content, of which:
• 33% is in the intracellular fluid, and 21.5% is in the extracellular fluid.
- The female body consists of:
• 50% water content, of which:
• 27% is in the intracellular fluid, and 18% is in the extracellular fluid.
- In 2008, the Human Tissue Act was established, a legislation governing the
collection and use of tissue, primarily from dead human bodies, and sets up a
framework for informed consent during the life of the person for human tissue
collection and use.
- Bodies come from bequest, rather than from condemned criminals and/or
unclaimed bodies.
- Involves:
• 1. Voluntary donation of bodies
• 2. Requires dual signed consent by the donor and an immediate family member
• 3. Most bodies are held for ~18 months, however body parts can be kept for
longer periods for teaching and research.
The Anatomical Position, Planes and Direction
- The anatomical position is a defined reference point for anatomy.
- Position is:
• Upright
• Face forward
• Feet together
• Palms face forward (supinated)
• Remains the same regardless of movement/spatial rearrangement.
- The anatomy is the structure of an organ system, and the relationship between its
constituents.
- The physiology is the function of an organ system and its constituents.
Homeostasis:
- Homeostasis is the presence of a stable internal environment.
- Failure to maintain homeostasis soon leads to illness or even death
- Homeostasis is the central foundation of modern physiology.
- Homeostatic regulation is the adjustment of physiological systems to preserve
homeostasis in environments that are often inconsistent, unpredictable, and
potentially dangerous
- All homeostatic regulatory mechanisms consist of:
• A receptor which senses stimuli
• A control/integration centre which receives and processes the information
• An effector which responds to the stimulus
- Homeostatic control is not precise - it maintains a normal range, oscillating close
to a set point, rather than an absolute value
• Each individual will have their own normal range within which their levels of a
given variable fluctuate
• The population has a reference range based on the breadth of individual normal
ranges within a population. The population reference range tends to be wider
than normal fluctuations within an individual.
- Most individuals will have a set point within the population reference range
- In some cases, to maintain homeostasis, a change in set point (or reference range)
may be necessary, e.g:
• In a change in altitude, red blood cell count change is necessary to have a
sufficient oxygen carrying capacity
• In a shift to a location with a different climate, the BMR may be necessary to be
changed
• In a fever, the set point for the body’s temperature is temporarily changed.
- Basal metabolic rate (BMR) is the body’s rate of energy expenditure under basal
conditions, where the person is:
• Awake
• At physical and mental rest
• Lying down
• No muscle movement
• At a comfortable temperature
• Fasted for 12-18 hrs.
,Tissues:
- There exist trillions of cells in the human body, yet only about 200 different types
of cells.
- A tissue is a collection of similar cells and cell products that perform a limited
number of specialised functions.
- The study of tissues is known as histology.
- There exist four basic types of tissue: epithelial, connective, muscle and nervous
tissue.
Epithelial Tissue:
- Epithelial tissue consists of epithelia and glands, and it:
• Covers exposed surfaces
• Lines internal passageways and chambers
• Forms secretory glands.
- However, all cells of epithelial tissue share the property of polarity i.e they have
one apical and one basal end (with basolateral sides), both with different structural
and functional differences.
- Functions of epithelial tissue include:
• Provides physical protection from abrasion, dehydration and destruction by
chemical or biological agents.
• Controls permeability i.e selectively permeable.
• Provides sensation via nerves which extensively innervate most epithelia.
• Produce specialised secretions via gland cells in epithelia or glandular
epithelium.
Connective Tissue:
- Consists of cells dispersed in a matrix.
• The major component of the matrix is a ground substance, often crisscrossed by
protein fibers.
• i.e matrix = cells + ground substance + proteins
- Functions of connective tissue include:
• Fills internal spaces.
• Provides structural support.
• Stores energy.
• Protects delicate organs.
• Transports fluids and dissolved materials.
• Establishes a structural framework for the body.
• Defend body from invading microorganisms.
• Support, surround and interconnect other types of tissue.
- Connective tissue can be categorised into three sorts:
i). Connective Tissue Proper:
• Syrupy ground substance.
• Diverse types of cells.
• Can be dense or loose.
, • Dense connective tissue can be:
• Dense irregular
• Dense regular
• Elastic.
• Loose connective tissue proper can be:
• Areolar
• Adipose
• Reticular.
• Cell types can be sorted into fixed cells and wandering cells.
• Fixed cells include: melanocytes, fixed macrophages, mast cells, fibroblasts,
fibrocytes and adipocytes.
• Wandering cells include: Plasma cells, free macrophages, mesenchymal cells,
neutrophils, eosinophils, and lymphocytes.
• Fibers in connective tissue proper include:
• reticular fibers,
• collagen fibers,
• elastic fibers.
ii). Fluid Connective Tissue:
• Watery matrix with dissolved proteins.
• Distinctive cell populations.
• Either blood or lymph.
iii). Supporting Connective Tissue:
• Low cell diversity.
• Densely packed fibers in matrix.
• Protect soft tissues and support weight.
• Can be cartilage or bone.
Muscle Tissue:
- Contracts to produce movement.
- Includes:
• Skeletal muscle,
• Cardiac muscle,
• Smooth muscle.
Nervous Tissue:
- Conducts electrical impulses.
- Carries information.
- Nervous tissue consists of neurons and supporting cells called neuroglia, or glial
cells.
- Neurons:
• Have dendrites as branching appendages to the cell body which receive
information.
• Have an axon which conducts that information as electrical impulses to other
cells.
, • The cell body contains a large nucleus and a prominent nucleolus along with
various organelles.
- There exist several different types of neuroglia, each with specific functions.
General functions of neuroglia include:
• maintaining physical structure of nervous tissue,
• repairing nervous tissue framework after injury,
• performing phagocytosis,
• providing nutrients to neurons,
• regulating the composition of the interstitial fluid surrounding neurons.
- Overall in the human body,
• 50% of tissue is muscle tissue,
• 45% is connective tissue,
• 3% is epithelial tissue,
• 2% is nervous tissue.
- The male body consists of :
• 60% water content, of which:
• 33% is in the intracellular fluid, and 21.5% is in the extracellular fluid.
- The female body consists of:
• 50% water content, of which:
• 27% is in the intracellular fluid, and 18% is in the extracellular fluid.
- In 2008, the Human Tissue Act was established, a legislation governing the
collection and use of tissue, primarily from dead human bodies, and sets up a
framework for informed consent during the life of the person for human tissue
collection and use.
- Bodies come from bequest, rather than from condemned criminals and/or
unclaimed bodies.
- Involves:
• 1. Voluntary donation of bodies
• 2. Requires dual signed consent by the donor and an immediate family member
• 3. Most bodies are held for ~18 months, however body parts can be kept for
longer periods for teaching and research.
The Anatomical Position, Planes and Direction
- The anatomical position is a defined reference point for anatomy.
- Position is:
• Upright
• Face forward
• Feet together
• Palms face forward (supinated)
• Remains the same regardless of movement/spatial rearrangement.
