L16, 17 & 18: Organ Systems Flashcards
True or false: The word “visceral” relates to organs
True
In an organ, you have at least two tissues that work together. You have the main tissue and the __?__ tissue(s).
Sporadic
What is the integumentary system?
The skin and it’s derived organs.
hair, nails, glands, and nerve-endings
What are the 2 primary layers of the skin?
- Epidermis
- Dermis (corium)
(There is also a sub-layer known as the hypodermis)
Describe the contact between the dermis and the epidermis
Hummocky and ridged (dermal papilla protrude into the epidermis to counter shear forces)
The epidermis forms a waterproof barrier made up of multiple strata. What are these strata (starting at the top)
Stratum corneum Stratum lucidum Stratum granulosum Stratum spinosum Stratum basale/germinativum
What fixture holds stratum basale to the basement membrane?
Hemidesmosomes
Stratum granulosum contains cells with granular cytoplasm. What do these cells do?
Secrete lipids to waterproof the skin
What is melanin?
A pigment secreted by melanocytes. It is passed to keratinocytes where it surrounds the nucleus and protects it from UV damage.
True or false: Melanocytes are protected from UV damage
False. They pass the UV-blocking melanin to keratinocytes and are left unprotected
What are Merkel cells?
Discs that ‘feel’ or are sensitive to touch. Slow-adapting and possibly play a neuroendocrine role.
Stratum spinosum has a spiny/thorny appearance (hence the name). Describe the structure of stratum spinosum.
8-10 layers of polygonal cells (keratinocytes) attached to each other by desmosomes (cadherin proteins).
The keratinocytes in stratum spinosum display pyknosis. What is this?
Darkened nuclei that are an early sign of apoptosis/autophagy
By what method is melanin delivered to keratinocytes?
Cytocrine transfer: direct delivery of cytoplasm and organelles between cells
What are Langerhans cells?
Langerhans cells (intraepidermal macrophages) are found specifically in the spinosum. Created in the bone marrow; transfer to the epidermis to aid immune cells.
Describe a melanocyte
A cell in contact with the basement membrane with tendrils that extend up through the epidermis enabling cytocrine transfer of melanin pigment
Describe the structure of stratum granulosum
Consists of 1-5 layers, superficial layers are often anucleate (apoptosis began in the spinosum)
What is characteristic of the cells in stratum granulosum?
They have a granular appearance due to the build up of keratohyalin proteins, and are often anucleate - or in the process of denucleation
True or false: Epidermal polymodal free-nerve endings encompass all layers of the epidermis
False. Epidermal polymodal free nerve endings encompass all layers up to the stratum granulosum
Stratum lucidum is the second layer from the top. Describe it
(Lucid = clear) 3-5 layers of anucleate cells. Contains eleidin (a type of keratin)
What is the top layer of the epidermis?
Stratum corneum. It is made of dead, flat cells that are full of keratin to make a waterproof barrier
What is desquamation?
Shedding of cells
A cell’s journey from the basale to the surface takes 2-4 weeks. What major processes take place in this time?
Keratinisation and apoptosis
What is the name of the layer of skin beneath the epidermis?
Dermis
What type of tissue is the dermis?
Connective tissue
What are the two sublayers within the dermis?
1) Papillary
2) Reticular
What proportion of the dermis is taken up by the papillary layer?
One fifth
The papillary layer is made of loose areolar connective tissue. What does “areolar tissue” mean?
Loose and irregularly arranged
What are papillae?
Ridges on the papillary layer that cause fingerprints in thick skin on hands and feet
Define “corpuscle”.
A minute body or cell
What are Meissner’s corpuscles?
Mechanoreceptor in the papillary layer that detect light touch
Do Meissner’s corpuscles have encapsulated or free nerve endings? Are they myelinated?
Encapsulated; non-myelinated.
Meissner’s corpuscles detect touch. Are they slowly or rapidly adapting?
Rapidly adapting (e.g. you stop feeling your clothes)
True or false: The papillary layer is avascular
False. It is highly vascularised.
What three shapes can you get from fingerprints?
- Loops (60-70%)
- Whorls (25-35%)
- Arches (5%)
Which layer of the dermis is dense and irregular?
Reticular layer
In which layer would you find hair follicles?
Reticular layer
Fill in the gaps:
__1__ corpuscles detect deep touch, pressure and __2__. They are __3__ adapting and can be found in the __4__ layer.
1) Pacinian
2) vibration
3) rapidly
4) reticular
Fill in the gaps:
__1__ corpuscles detect stretch. They are __2__ adapting and can be found in the __3__ layer.
1) Ruffini
2) slowly
3) reticular
What mode of secretion takes place in sudoriferous glands?
A) Apocrine
B) Holocrine
C) Merocrine
D) Endocrine
C) Merocrine
Sudoriferous glands are sweat glands
In which layer of the skin are the ducts of the merocrine sudoriferous glands located?
Reticular layer
True or false: The Meissner’s, Pacinian and Ruffini corpuscles are all encapsulated mechanoreceptors?
True
What mode of secretion takes place in sebaceous glands?
A) Apocrine
B) Holocrine
C) Merocrine
D) Endocrine
B) Holocrine
Sebaceous glands secrete oil/sebum
If a mechanoreceptor is large with vague borders, what could it be?
Either a Pacinian or Ruffini corpuscle
If a mechanoreceptor detects the stimuli throughout it’s contact, what type could it be?
It must be slowly adapting, therefore either Merkel’s disc or Ruffini corpuscle
If a stimulus is picked up by a Meissner’s corpuscle, will the sensation remain throughout the contact?
No, as Meissner’s corpuscles are rapid adapters
What is the name given to the part of the integumentary system that attaches the skin to the underlying organs?
Hypodermis
subcutis, superficial fascia
In which part of the integumentary system might you find adipose tissue?
Hypodermis
In which part of the integumentary system might you find dermal papillae?
Dermis, in the papillary layer
What accessory organs might you find as part of the integumentary system?
Hairs
Nails
Glands
Hairs are epidermal growths that have what three functions?
1) Protection
2) Thermoregulation
3) Display
What components are involved with hair?
1) Shaft, root, follicle
2) Sebaceous glands
3) Arrector pili muscle
4) Hair root nerve plexus (touch)
What is vellus hair?
Short, thin hair that covers most of the body. May be converted into terminal hair in some areas (armpit, pubic, beard etc..)
What is lanugo?
The woolly hair that covers babies - present in utero
What response occurs when body temperature rises above normal?
Nervous system signal dermal blood vessels to dilate and sweat glands to secrete, to bring temperature down.
What response occurs when body temperature drops below normal?
Nervous system signals dermal blood vessels to constrict and sweat glands remain inactive, to conserve heat. Muscles may contract involuntarily to generate heat.
Why are abrasions typically more painful than lacerations?
More nerves are damaged in abrasions
A patient presents with black eschar scabs. What do they have?
Third degree burn
Fill in the gap:
Sunburn is a __?__ degree burn.
first
Which type of burn blisters?
Second degree
Which skin cancer:
- occurs in stratum basale
- has a pearl-like appearance
- is the most common cancer
- rarely metastasises
Basal cell carcinoma
Which skin cancer:
- occurs in stratum spinosum
- occurs in the elderly
- is the second most common cancer
- can metastasise
Squamous cell carcinoma
Which skin cancer:
- involves the melanocytes and existing moles
- can metastasise
- can be lethal
Malignant melanoma
How do you identify a malignant melanoma?
ABCD
Asymmetry
Border is irregular
Colour is mixed
Diameter >6mm
What are the four types of injection site?
- Intradermal
- Intravenous
- Subcutaneous
- Intramuscular
True or false:
The cardiovascular system is involved in temperature regulation, immunity, and acid-base balance.
True
Which system is involved in:
- Ventilation/gas exchange
- Acid-base balance
- Communication
- Defence from pathogens
Respiratory system
What are the three components of the cardiovascular system?
- Blood
- Heart
- Blood vessels
True or false:
Blood is typically slightly acidic
False, it should be slightly alkaline (pH 7.35-7.45)
True or false: Blood is a type of tissue
True. Blood is classified as connective tissue
What are erythrocytes?
Red blood cells
What is the scientific name given to white blood cells?
Leukocytes
Which components of blood are anucleate?
Erythrocytes and platelets/thrombocytes
What are thrombocyte?
Platelets
Which white blood cells are involved with specific immunity?
Lymphocytes
Which white blood cells are involved with allergens/parasites?
Eosinophil
Which white blood cells are involved with histamine/heparin?
Basophil
Which white blood cells are active phagocytes?
Neutrophil
Which white blood cells are macrophages?
Monocytes
What is the role of erythrocytes with regards to gas exchange?
Erythrocytes contain haemoglobin to bind O2 and CO2 for gas exchange
True or false: While CO2 can bind to erythrocytes, most of it is transported in the plasma in dissolved form.
True
What are alveolar type I cells?
Squamous alveolar cells
What are alveolar type II cells?
Septal cells
Which nerve has a positive chronotropic effect (increases HR) and a positive inotropic effect (increases force of contraction)?
Cardiac accelerator
What is the route taken by electrical activity from the SA node?
SA node –> intermodal tracts –> AV node –> bundle of His –> interventricular septum –> Purkinje fibres
What effect does vagal tone have on the sinus rhythm of the SA node?
Decreases it
What are the three main layers of blood vessel walls?
Tunica externa (outermost)
Tunica media (middle)
Tunica intima (innermost)
Which of the blood vessel tunics contains elastic and collagen fibres?
All three of them
Which blood Bessel tunic is made of concentric smooth muscle tissue?
Tunica media
Which blood vessel tunic is made from squamous epithelium (endothelium) and basement membrane?
Tunica intima
The aorta and pulmonary trunk are examples of what type of blood vessel?
Elastic (large) arteries
What is vasa vasorum?
The blood supply that supplies large arteries
Elastic (large) arteries have a very elastic tunica media, with very few muscle cells. What effect does this elasticity have?
Maintains blood pressure, evens out pulse force
True or false: Elastic (large) arteries have their own blood and nerve supply
True
Which of the following is NOT true of large veins?
A. All 3 tunica layers
B. Relatively thick tunica media
C. Vasa vasorum
D. Nerve supply
B. Relatively thick tunica media
Large veins have a relatively thin tunica media
The majority of arteries are __1__ (medium) arteries - also called __2__ arteries.
- muscular
2. distribution
True or false: Muscular arteries do not have a vasa vasorum
False. Larger muscular arteries have a vasa vasorum and a nerve supply.
What is the function of smooth muscle cells in tunica media?
Change the diameter of the lumen (vasoconstriction/ vasodilation)
Where are valves found in medium sized veins?
Tunica intima
Arterioles are also known as __?__
Resistance vessels
True or false: Arterioles have thin, incomplete or no tunica externa and a thin or incomplete tunica media
True
Although the tunica is thin or incomplete, arterioles are still capable of vasoconstriction/ dilation
Which of the following are true of venules:
A. Collect blood from capillaries
B. Contain valves
C. Posses all three tunics
D. All of the above
D. All of the above
Which of the following is NOT true of capillaries:
A. Endothelial tube inside thin basement membrane
B. No tunica externa
C. Thin tunica media
D. Diameter is fairly similar to red blood cell
C. Thin tunica media
Capillaries have no tunica media
What are the three types of capillary?
Continuous
Fenestrated
Sinusoidal
Where would you find fenestrated capillaries?
Kidney
Where would you find sinusoidal capillaries?
Spleen, bone marrow
What controls capillary bed perfusion?
Sphincters from the metarteriole
What term describes peak arterial pressure during ventricular contraction?
Systolic pressure
What term describes minimum arterial pressure during ventricular relaxation?
Diastolic pressure
What is pulse pressure?
Difference between systolic pressure and diastolic pressure
What is mean arterial pressure (MAP)?
diastolic pressure + a third pulse pressure
Which of the following will increase BP?
A. Increase lumen diameter
B. Decrease vessel length
C. Increase blood viscosity
D. Decrease venous return
C. Increase blood viscosity
What do the kidneys do in response to hypoxia?
(hypoxia = low oxygen)
Kidneys release erythropoietin which compels bones to produce red blood cells
What 6 components make up the urinary system?
Kidneys (x2)
Ureters (x2)
Urinary bladder
Urethra
What are the three tubes connected to the kidney?
Renal artery, renal vein, ureter
What is the hilus
A central fissure on the exterior of the kidney
Each renal lobe consists of what?
1 renal pyramid, overlaying area renal cortex, half of each adjacent renal column
What is a nephron?
A functional unit in the kidney
What are the two parts of a nephron?
Renal corpuscle
Renal tubule
What components make a renal corpuscle?
- Glomerulus
2. Bowman’s capsule
What components make a renal tubule?
- Proximal convoluted tubule
- Loop of Henle
- Distal convoluted tubule
- Collecting duct
What is the relationship between the glomerulus and Bowman’s capsule?
Bowman’s capsule envelopes the glomerulus
Where would you find a ball of fenestrated capillaries?
The glomerulus of the renal corpuscle
Where is blood filtered to create a plasma-like filtrate?
Glomerulus
Where does water get reabsorbed into the blood?
Can be reabsorbed all along the renal tubule
Is the renal corpuscle found in the cortex or the medulla?
Cortex
Which part of the nephron can be seen in the renal medulla?
The loop of Henle
