S1 A&p Flashcards
What is the order of the level of organisation
Chemicals, Cells, Tissue, Organ, Organ System
Define a Tissue and the types:
A composition of similar cells working together to perform a specific function.
Epithelial, Connective, Muscle and Neural
What is Homeostasis
Is the maintenance of a constant internal environment
What are the two bodily cavities and what do they contain
Dorsal - Brain and Spinal Cord
Ventral - 2 sub cavities (thoracic - heart and lungs, Abdominopelvic - most major organs
Define Negative and Positive Feedback
Negative - oppose variations from normal
Positive - Exaggerate the variation
3, Functions of the nervous system
Monitors internal and External environments
Integrates sensory information
Coordinates voluntary information and involuntary responses.
What do the CNS and PNS do and contain
CNS - Brain and spinal Cord. Integrates and coordinates the processing of sensory data
PNS - Includes all the neural tissue outside the CNS and delivers sensory info to the CNS. It carriers out motor commands.
Name the 4 types of neurons and different features
Anaxonic - very small and have no anatomical features to differentiate axon from dendrite (circular).
Bipolar - cell body lies in between axon and dendrite
Unipolar - cell body is offset
Multipolar - Have two or more dendrites and a single axon
What brings sensory information to the spinal Cord
Dorsal root ganglia containing the cell body of sensory neurons.
Function of the spinal Cord
To send motor commands from the brain to the body, and to send sensory commands from the body to the brain
What is in grey and white matter in the spinal Cord
Grey - Cell bodies and neuroglia cells
White - Myelinated and Unmyelinated axons
What are the 6 major regions of the brain (4 of which make the brain stem)
Cerebrum
Cerebellum
Diencephlaon
Midbrain
Pons
Medulla Oblongata
Function of the Cerebrum, and the 4 lobes within
Responsible for conscious thought, intellectual function, regulation of skeletal muscle contraction, movement’
Temporal, Frontal, Parietal, Occipital
Cerebellum Functions
Coordinates somatic motor patterns involving posture and balance, vision, movement, cognitive function
What does the Diencephalon contain and whats their functions
Thalamus - Relay and processing centre for sensory information
Hypothalamus - Emotion control, autonomic function and hormone production
Midbrain function
Processing of visual and auditory data
Medulla Oblongata function
Relays sensory information to the thalamus and other parts of the brain stem. Also regulates visceral function
What are the 3 brain protective mechanisms
Bones of the cranium,
Cranial Meninges,
Cerebrospinal Fluid
What are cranial meninges
Membranous coverings that provide a support framework to the skull
What are the 3 layers of the cranial meninges
(Different matters)
Dura mater
Arachnoid Mater
Pia matter
Name the 12 cranial Nerves
O,O,V,O,T,A,A,H,T,F,G,V
Olfactory
Optic
Vestibulocochlear
Oculomotor
Trochlear
Abducens
Accessory
Hypoglossal
Trigeminal
Facial
Glossopharyngeal
Vagus
What is a membrane potential and a potential difference
Membrane potential - IS the difference in electrical potential between inside and out of a cell
Potential difference - an uneven distribution of charges
What is depolarisation of the membrane
When the membrane is changes to a less negative value
how is a local (action) potential created
Membrane is depolarised past a threshold value which triggers the activation of Na channels which leads to accelerated depolarisation.
How does the membrane return to resting potential
Na channels are inactivated and K channels are activated to allow the cell to return to normal permiability.
What is propagation
When the local potential spreads down the membrane of the neuron towards the dendrite
When does saltatory propagation occur
In myelinated axons, when action potential must jump from one node to another.
What is the synapse and how does it transfer information
The site of communication between a nerve and some other cell.
Via neurotransmitters from the synaptic terminal
What does the synaptic terminal contain
Mitochondira, synaptic vesicles (containing specific neurotransmitters) and ER
What are neurotransmitters
Chemical compounds released by 1 neuron to effect the membrane potential of another
What are the two types of neurotransmitter and what do they do
Excitatory - cause the depolarization of the postsynaptic membrane to promote an action potential
Inhibitory - cause hyperpolarisation of postsynaptic membranes and supress action potentials.
What are examples of neurotransmitters
Acetylcholine, dopamine, nor-adrenaline, seratonin and GABA
Epithelial Tissue structure and function
Is layers cells that form the linings of membranes and glands.
How are epithelial tissues classified
Layers (simple - single layer, stratafied - 2 or more layers)
Shape (squamous - thick, Cubodial - cube like, Columnar - tall slender oval shaped, Transitional - several layers that become flattened when stretched)
Connective tissue function
Support and Protection. Filling internal spaces, provide structural support and store energy
what do connective tissue contain
Fibroblasts, adipocytes, marcrophages, fibres like collagen
Difference between dense (regular and irregular) and elastic connective tissue
Dense - Regular provides firm attachments and conducts the pull of muscles.
Irregular provides strength to resist forces being supplied (overexpansion of organs).
Elastic - stabilizes, by cushioning shock and permitting expansion and contraction. It is found between vertebrae
What are the three types of cartilage elastic tissues
Hyaline - Provides stiff but flexible support and reduces friction between bones
Elastic - Provides support but can tolerate distortion without damage.
Fibrocartilage - Resists compression and prevents bone to bone contact whilst limiting movement.
Describe Skeletal Muscles (3)
Are controlled voluntarily
Are striated and multi nucleated
Are large celled that are controlled via nerves
Describe Cardiac muscles and an example (6)
Are controlled involuntary
Are smaller with striated cells
Are controlled by pacemaker cells
They contain intercalated disks held together by electrical connections
E,g, the heart wall
Describe Smooth Muscle and an example (5)
Are under involuntary control
Small celled and not striated
Controlled by pacemaker cells
Are involved in hormonal control
E.g. visceral organs
What are the three types is glandular secretions and there ways
Merocrine - Secretory vesicles are released without damaging the cell,
Apocrine - Part of the cell is released along with a secretory vesicle,
Holocrine - Entire cell dies and releases its contents
What is the Fasicae connective tissue
A thin, flexible, connective tissue that surrounds and supports every structure in the body
What are the layers of fasciae
Superficial, deep, subserous
What are the 4 types of membranes
Mucus - Line the inside of organs
Serous - Line ventral cavities
Cutaneous - Covers the bodies surface (skin)
Synovial - line joint cavities
Skeleton Function
To support the bodies structure. Give it its shape and allows for movement and protection
What is the axial and appendicular skeleton
Axial - Main trunk of body (head, neck, Back, Chest).
Appendicular - The limps and bones that support them.
What are the 6 types (shapes) of bones
Flat, Long, Short, Irregular, Satural, Sesamoid
Describe the general structure of a long bone
Have a long diaphysis (shaft) and a strong outer layer surrounding the medullary cavity.
The epiphysis (ends) contain spongy trabecular bone which acts as a network for cross bridges
What is bone tissue made of (3)
Ground substances
Proteins to reinforce
Bone cells
Describe a compact bone
Contains osteon.
Columnar
Strong
central canal to allow blood vessel supply
lamellae, concentric layers of the matrix
Lucane, which contains cells like osteocytes
Describe trabecular bones
Contains no osteons
Is made from long thin peices of tissue called trabeculae
Contains arches, rods and plates of bones in a branching network
What do Osteoclasts, osteoblasts and osteocytes do
Clasts - Crush old bone so that it can be replaced
Blasts - form the new bone
Cytes - sits inside the bone and is responsible for maintaining it, they dissolve it and add calcium.
What is intramembranous ossification and how does it happen
The formation of flat bones
Mesenchymal cells differentiate into osteoblasts
What is endochondral ossification
Is the formation of the cartilage model and most bones (apart from flat)
How does bone width grow
Appositional bone growth, bony tissue is added to the surface of bones.
What are the requirements for bone growth
Minerals, Vitamins, Hormones and loading
What is bone remodeling
When calcium storage/release is altered to allow the bone to adapt to the mechanical requirements
What are the factors that affect bone remodelling (3)
Breakdown and reforming of bone tissues
Adaption to loading
Calcium Homeostasis
How are fractures healed
Formation of a haemotoma (acts as a matrix) which is replaced by calluses, that are gradually replaced by bones
The clot holds the bone fragments in place and stops any bleeding
What is the cranium, and what does it consist of:
(SOFET)
Part of the skull that protects and encloses the brain
Frontal bones, paretial bones, temporal bone, occipital bone, sphenoid bone, ethmoid bone
What are the facial bones for
Supports and protects cavities and sensory organs. Include Attachments of mucles and structures for mastication (chewing), speech and facial expression
What are the facial bones (6)
Maxillary bones
Zygomatic bones
Mandible
Nasal Bones
Nasal Conchae
Nasal septum
Describe the basic structure of a vertibrae
Body - for weightbearing, articualtions with above and below
Arch - pedicle and lamina, to support processes
Intervertebral disks - seperation, protection and shock absorption
Vertebral Foramen - Protects spinal cord
Processes - Used for attachment
What are the transverse, spinous and articular process in vertebraes used for
Transverse and spinous - Muscle attachment
Articular - articulate with the vertebrae above and below
How are Cervical Vertebrae different
Upper part of spine
Oval body and transverse foramina, Has a bifi split spinous process to support the neck
How are thoracic vertebrae different
Middle of the Spine
Has a heart shaped body with two points of attachment for the ribs
Long downward facing spinous process to allow for more muscle attachment and movement
How are Lumbar Vertebrae different
Bottom of Spine
Are large and heavy to support more weight
What is the function of the ribcage
For protection of the thoracic content (Heart and lungs), and to allow for expansion and contraction for ventiltion
Describe the structure of the ribs (Type of bone, articulations)
Seven pairs of true ribs and five pairs of false ribs.
The ribs are a curved flat bone.
The heads articulate with the vertebral body and the tubercle articulates with the transverse processes of the vertebrae.
What are the main differences in male and female skeletons
Pelvic angle (male often less than 90, female often over 100) to allow for child birth.
Males tend to have longer long bones.
What are the 3 main types of joints, their range of movement and examples
Synathrosis - an immovable joint, skull
Amphiathrosis - are slightly movable, pubic bone
Diathrosis - Are freely movable, shoulder
What is circumduction
The circular motion of a joint without rotation
A combination of abduction and adduction
What is a synovial joint
A joint that allows bones to move against each other, and is the most common type of joint in the body.
What are the structures of a typical synovial jount (3)
Articular Cartilage
Synovial Fluid
A joint capsule
What does articular cartilage do
It is a smooth covering that prevents bones in a synovial joint from touching each other to reduce friction and allow smooth movement.
What is synovial fluid
A high protein content fluid that sits in the joint cavity and plays a role in lubrication, nutrient distribution and shock absorption. It is secreted by fibroblasts.
What is a joint capsule
Is a fibrous connective tissue that seals the joint space to provide passive stability by limiting movement.
What are the 5 common accessories of a synovial joint
Cartilage - To cushion the joint
Fat pads - to provide protection
Ligaments - To support the joint
Tendons - to attach muscle
Bursae - pockets of synovial fluid that cushion the tendons where ligaments rub
What are the 3 common joint injuries
Sprains - Tearing of ligament fibres
Dislocation - The displacement of articulating surfaces which can cause damage
Subluxation - A Partial dislocation
What are the 3 common joint diseases
Osetoarthritis - Damage to articulating cartilage and underlying bone, an inflammatory condition
Rheumatoid Arthritis - An autoimmune condition that causes inflammation of the Articular cartilage
Gouty Arthritis - The deposition of crystals in the joints as a result of a metabolic disorder
What are the main functions of skeletal muscles (4)
Movement
Maintenance of posture
Thermoregulation
Storing and moving substances
What do tendons do
Tendons connect the muscle to bones, and transmit the force produced by the muscle to the skeleton
What is skeletal muscle composed of
A Bundle of cylindrical striated cells called fibers, each of these are called a fascicle.
What are muscle fibres made from
Each are a collection of hundreds of banded myofibril and are the contractile element of the muscle
What is the order from smallest to largest in muscle fibres
Myosin and Actin
Sacromeres
Myofibril
Fibres
What are thick filaments in muscles
Are highly ordered assemblies of protein molecules called myosin.
What are the myosin subunits and their function
Long rod shapes tails
Globular heads
That form cross bridges between thick and thin filaments
What are thin filaments in muscles
Are highly ordered assemblies of the protein molecule actin. They are pear shaped. They are joined together like two strings of beads
What does titin, nebulin, and desmin do in muscle fibres
Titin acts as a molecular spring
Nebulin and Desmin act as a scaffold
What are the characteristics of slow twitch muscle fibres
(mATPase activity, cross sectional area, Max force, Max shortening velocity, Max power, Appearence, Energy source, Main metabolism, Mitochondrial density, Endurance Capacity)
mATPase activity - Slow
cross sectional area - Small
Max force - Low
Max shortening velocity - Slow
Max power - Weak
Appearence - Red
Energy source - Fat
Main metabolism - Oxidative
Mitochondrial density - High
Endurance Capacity - High
What are the features of Fast Twitch (Oxidative) muscle fibres
(mATPase activity, cross sectional area, Max force, Max shortening velocity, Max power, Appearence, Energy source, Main metabolism, Mitochondrial density, Endurance Capacity)
mATPase activity - Fast
cross sectional area - Medium
Max force - Intermediate
Max shortening velocity - Fast
Max power - Intermediate
Appearence - Pink
Energy source - Fat/glycogen
Main metabolism - Oxidative/glycolytic
Mitochondrial density - Intermediate
Endurance Capacity - Intermediate
Features of Fast twitch (Glycotic) muscle Fibres
(mATPase activity, cross sectional area, Max force, Max shortening velocity, Max power, Appearence, Energy source, Main metabolism, Mitochondrial density, Endurance Capacity)
mATPase activity - Very Fast
cross sectional area - Large
Max force - High
Max shortening velocity - Very Fast
Max power - High
Appearence - White
Energy source - Glycogen
Main metabolism - Glycolytic
Mitochondrial density - Low
Endurance Capacity - Low
What is the sliding filament mechanism
During contraction, filaments slide past each other. Each of the filaments remain relatively unchanged in length despite changes in the growth muscle length.
What is the cross bridge cycle
Is how the sarcoplasmic reticulum regulates the intracellular calcium levels, and hence allows for muscle contraction.
What are the basic structures of a motor neuron
Cell body with surrounding dendrites
An axon covered by myelin sheaths
Information is passed from node to node over the gaps of the sheath called ranvier to the terminal branches of the axon
What are the 4 steps of a nerve impulse being transmitted from the spine to the muscle for contraction
1- Sensory neurons send signals to relay neurons
2- They connect sensory neurons to motor neurons
3- Motor neurons send electrical signals to the receptor
4- A response occurs (contraction)
What are the two sensory receptors that regulate muscle contraction
Golgi tendon organs
Muscle spindles
What does the golgi tendon organ do
Senses tension in the tendon when the muscle contracts. When excessively large forces are generated, feedback from the GTO causes a decrease in muscle activation and works as a protective mechanism
What do muscle spindle receptors do
Are highly specialized muscle fibers positioned parallel to the normal fibers. They are sensitive to change in muscle length, so that when the muscle is stretching rapidly, the muscles spindles can contract and maintain tension in the middle of the fibers to prevent overstretching
What are the 5 special senses
Smell
Taste
Vision
Touch
Balance
Define Sensation and Perception
Sensation - Sensory information arriving to the CNS
Perception - is the conscious awareness of a sensation
Where are the olfactory organs located
In the upper nasal cavity, on either side of the nasal septum
How is smell perceived
1 - AS we breath air, it swirls in the nasal cavity
2 - When it reaches the olfactory organs, the primary receptors on the cilia allow lipids and water soluble molecules to diffuse into the mucus, stimulating the receptors
3 - The Oderants that stimulate bind, and change the receptors permeability and create an action potential
4 - This information is relayed to the CNS where the smell is interpreted.
Where are taste receptors located
Over the superior surface of the tongue and the adjacent pharynx and larynx
What are the taste sensory structures
They are taste buds, which are taste receptors and specialized epithelial cells that lie within very small pores of epithelial projections called papillae.
What do taste buds contain
Gustatory cells - which extend tiny micro-villi into the surrounding fluids through the taste pore
Supporting cells
How is taste sensed
By dissolved chemicals contacting taste hairs that stimulate a change in the membrane potential of the taste cell. This results in an action potential in the sensory neuron
How does light enter the eyes
Via refraction at the cornea and lens
Is then absorbed by the retina by the photoreceptors - rods and cone cells
What are cones and rod cells responsible for
Cones - Colour vision and daylight vision
Rods - Low light intensity and peripheral vision
What happens to rhodopsin when light enters the eye, and what happens next
In the presence of light, rhodopsin splits, altering the flow of electrical currents
The thalamus then relays visual information to reflex centres in the brain stem as well as the visual cortex of the cerebrum.
Where is the sensory receptor for hearing and equilibrium
Is within a complex located on the temporal bone of the skull in the inner ear
What is the mechanoreceptor for Hearing and equilibrium
Hair cells
How are equilibrium sensations provided
Hair cells of the vestibular apparatus (the semi circular canals and otholis) respond to circular movements
What are the two components of the otholis and where is it found
Urticle - Which controls horizontal accelerations
Sacculem - Which controls vertical linear accelerations and gravity
In the ear
What is the the integumentary system and its main functions (6)
The outer layer of the body (skin, hair, nails, etc)
Protection
Excretion
maintenance of body temp
Production of melanin and keratin
Synthesis of Vitamin D
Sensation
What are the two components of the integumentary system
The cutaneous membrane (skin) and the accessories (hair, nails)
What are the three layers of the cutaneous membrane from most superficial to least
Epidermis
Dermis
Hyperdermis
What is the epidermis
IS the outer layer of skin
Is made from stratified squamous epithelial tissue.
It has 5 layers, or strata, that all have unique functions
It provides protection and allows for regeneration
What is the Dermis and its functions
Is the inner layer of the two main skin layers
It keeps a strong outer layer by supporting the epidermis with collagen and elastin fibres.
It houses blood vessels and sensory organs
What are the layers of the dermis
A papillary layer (from areolar tissue)
Reticular layer (made from fibrous networks)
What is the hyperdermis (3)
IS the lower layer of skin
It contains loose connective tissue fibres (areolar and adipose) that are interwoven with the reticular layers of the dermis.
It allows for movement relative to the underlying structures
How is the epidermis regenerated (4)
Stem cells - Epidermal stem cells in the basal layer of the skin generate new cells.
Cell migration - The new cells move up through the epidermis toward the surface.
Keratinization - The cells that produce keratin undergo biochemical and morphological changes, forming the layers of the skin.
Exfoliation - The uppermost cells dry out, become keratinized, and are shed as tiny flakes of skin.
Features of thick skin
(locations, epidermal; strata, ridges.
Hair follicles, sweat glands, sensory receptors)
location - Fingertips, palms, soles
strata - Thicker
ridges - Present
Hair follicle - Absent
Sweat glands - More
Sensory receptors - More
Features of thin skin
(locations, epidermal: strata, ridges.
Hair follicles, sweat glands, sensory receptors)
location - Everywhere apart from hands and feed
strata - No to little strata
ridges - Absent
Hair follicle - Present
Sweat glands - Less
Sensory receptors - Less
Function of hair follicles
To provide protection, insulation and sensation
Describe the structure of hair (3)
Medulle (core) - a cortex of thick layers of hard keratin for stiffness
Cuticle - provides toughness
Internal root sheath - surrounds the hair root and deeper portion of the shaft
How does hair grow (3)
Basal cells in the hairs matrix divide
Daughter cells are pushed towards the surface
They become increasingly keratinised
How does the hair growth cycle end (2)
Follicle becomes inactive
Connections between the hair matrix and root breaks down
What is sweat glands function (3)
Skin surface cooling, excretion and protection
Whats the difference in Apocrine and merocrine sweat glands
Apocrine - Secrete thick odorous fluid into hair follicles in axillae/pubic regions
Merocrine - Discharge water fluid onto the skins surface
