Biosciences for Nursing Workbook Week 2: The Skin, Wound Healing, Temperature Regulation

This workbook covers topics such as the structure of the skin, wound healing, and homeostatic control of temperature. It is designed to reinforce knowledge and understanding of biosciences for nursing students. The workbook includes labeling diagrams, matching terms with definitions, and describing the functions of cells found in the skin. It also covers the stages of wound healing and the process of temperature regulation.

Year 1
Biosciences for nursing
Workbook week 2
The skin
Wound healing
Temperature regulation
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text...............................
Student number Click or tap here to enter text.…………

2 Biosciences for nursing (Adult
Nursing)
Biosciences workbook
This workbook aims to further reinforce knowledge and understanding of
students on the systems of the body and to enable them to study at their
own pace. It is also a self- assessment tool for students to identify whether
learning has taken place. It encourages close reading of the lecture notes
and textbook to find the relevant information.
Learning anything new takes a lot of effort. Learning is an active process;
you need to engage with the work and practice writing the new ‘language’
down in your notebook (or online portfolio). Pay attention to how the words
are spelt for example, it is easy to confuse atria and arterial. Eventually this
language will become your own language. Reading is a very passive activity,
reading alone is not a good way to learn, you need to engage fully by
questioning everything you read. This workbook is designed to help you with
this, however, just completing the workbook is not enough, if this subject is
new to you will have to go over it many times.
Although many of the answers can be found in the lecture notes, not all can
be found here. Please use your textbook to read around the subject to
extend your knowledge and understanding. However, there is often much
more in textbooks than you need to know. In order to help you focus on what
you need to know the learning outcomes for each session are given to you.
In this workbook there is a separate section for each lecture. Please
complete and submit (workbook submission portal) the relevant section
following your lectures in preparation for the ‘live’ quiz. If you leave the work
for a few weeks, you will find it very difficult to catch up.
Read you lecture notes and textbook prior to completing each section. Can
you answer the questions without looking back at your notes? Sometimes
the same question is repeated in a different way. This is deliberate as
repetition helps us to remember.
Good luck!

5
4 6
7
8
3 9
2 13
1
Structure of the skin
1. Label the following diagram using the corresponding labels from the list:
Arrector pili muscle; Adipose tissue; Hair follicle; Nerve fibres; Sudoriferous
gland; Sebaceous gland; Hair shaft; Stratum corneum, Stratum basale, Hair
bulb; Epidermis; Dermis; Hypodermis (subcutaneous tissue)
10
11
12
1 – Sudoriferous gland
2 – Hypodermis
3 – Dermis
4 – Epidermis
5 – Hair shaft
6 – Stratum corneum
7 – Stratum basale

8 – Sebaceous gland
9 – Arrector pili muscle
10 – Nerve fibres
11 – Hair follicle
12 – Hair bulb
13- Adipose tissue\

2. Using the key choices, select the correct letter for the term with the definition
given.
a. Stratum basale e. Hypodermis
b. Stratum corneum f. Papillary layer
c. Stratum granulosum g. Epidermis
(whole)
d. Stratum lucidum h. Dermis (whole)
Stratum lucidum Layer of cells present only in thick skin
Stratum corneum Layer containing all dead cells
Stratum corneum Layer that sloughs off
Papillary vessels Contains the blood vessels
Stratum basale Epidermal layer undergoing mitosis (cell
division)
Stratum granulosum Cells with most keratin in them
Epidermis (whole) Outer layer of skin
Hypodermis Deeper layer of skin
Stratum corneum Layer where accessory structures are found
Stratum basale Epidermal layer where most melanocytes are
found
Stratum granulosum Layer that produces lipid rich secretion
Stratum corneum Epidermal layer containing the oldest cells
Hypodermis Largely adipose tissue and anchors skin to
underlying tissue

3. For the protective functions of skin, match the term given with the definition of
the role each part plays in providing protection.
Just insert the appropriate letter found to the left of your chosen answer into
the answer column. Choose an answer from the following:
a. Melanin, b. Sweat, c. Normal flora, d. Skin, e. Macrophages,
f. Lipids, g. Langerhans cells, h. Keratin, i. Merkel cells
Merkel cells Involved in the sensation of touch
Keratin Resist invasion by organisms by preventing
harmful bacteria from colonising
Lipid Prevent some evaporation on skin, protects
hair and skin from drying out, antibacterial due
to low pH
Melanin Protects from UV light
Sweat Increases heat loss
Skin Forms a protective barrier and protects
underlying tissues
Macrophages Phagocytose bacteria and viruses
Collagen A tough fibrous protein
4. Name the 5 layers of the epidermis starting with the innermost layer:
The deepest layer of epidermis is Stratum basal which is also known as stratum germinativum.
Stratum spinosum, stratum granulosum, stratum lucidum and stratum corneum. It is symbolizing
as the outermost layer of skin made up of keratin and anucleate cells.
5. What is an exocrine gland? Describe.
Exocrine glands are symbolizing as the glands of the external secretion where the
substance are release from the ducts to body parts. They contain varied functions deeding
upon the organ to which they are associated with. The prime functions of these glands
are to absorb the nutrients in effective manner while protecting body temperature in
optimistic manner. It also helps body to digest the food and protecting the lining of the
tissues. Exocrine glands secrete the substance through either apocrine glands, merocrine
glands and holocrine glands. With the help of exocytosis process the merocrine glands
secrete their secretion to the body. From the holocrine glands, secretion occur when the

cell membrane burst to secrete out the substance. However, hypocrine glands form the
bud like structure of cell membrane which further breaks of into the duct directly.
6. List some of the structures found in the dermis
The dermis primarily consists of the nerve endings, sweat glands, sebaceous gland, hair foricles
and the blood vessels. Nerves endings sense the pain, touch or the temperature and sweat glands is
responsible for producing the sweat which helps to cool the body. However, sebaceous gland
secretes sebum to hair follicles which assist the skin to maintain the moist. Hair follicle is
responsible for protecting the individual from injury and blood vessels in the dermis is repose for
providing the required nutrients to the body.
7. List the cells found in the epidermis and briefly describe their function.
Epidermis is the topmost layer of your skin. Major role of epidermis is to protect the skin from
foreign particle while keeping your skin hydrated. Cells found in the epidermis are Keratinocytes,
melanocytes, Markel cells and Langerhans cells. Keratinocytes are present in around 90 percent of
the epidermis which is responsible for producing the keratin protein which is symbolize as the
main component of the epidermis. Melanocytes are present in approximately eight percent of
epidermal cells which are responsible for making your skin pigment. These cells product the
pigment known as melanocytes which assist the dermis from UV light. Langerhans cells is
responsible for preventing substance or particles into the skin. About one percent of epidermal cells
are Langerhans cells which acts the immune protecting cells. Less than one percent of epidermal
cells is Markel cells in epidermis which is responsible for connecting the nerve endings in dermis.

Wound healing
1. If the epidermis is damaged during injury, which layer of the epidermis enables
new cells to grow?
Stratum basale is responsible for recreating the loss which has occurred due to injury or
damaged in the body. when an injury begins in the epidermis, the inflammatory response begins
which leads to the formation of clot of scab which restricts the entry of microorganisms. After
the formation of scab, the stratum basal begins divide by the process of mitosis. To regrow the
cells in epidermis it is important to repaired the cells of dermis which is begin with stem cells
and fibroblast produce the collagenous fiber. These fibers support new blood vessels formation
in dermis after the dermis is restored the epidermal cells works in their layer regeneration by
collagen deposition and formation of the granulation tissue.
2. Name the cell(s) found in the skin that also function as cells of the immune
system and protect the skin from pathogenic organism.
Keratinocytes are symbolizing as the predominant cells which is located in outer part of the skin.
They behave as first line of inherent approach used against the infection. They act as an effective
barrier which protect body from the foreign substance or the infectious agent. Beside creating
physical barrier lying among the physical environment and the body it also supports the body from
anti-pathogen infections in the skin. They explicit the Toll-like receptors which are symbolize as
the pattern-recognition receptors. These receptors main role is to detect the molecules on
pathogens while triggering the inflammatory response for the stimuli. Through chemokines,
Keratinocytes attracts the other immune cells to the epidermis. Their major role is to produce the
pro-inflammatory mediators primarily the chemokines which attract monocytes, t-lymphocytes or
dendrite cells to the site of pathogen penetration.
1. State what happens during each stage of wound healing.
(Use your textbook to extend your understanding of each stage)
a. Inflammation
Inflammatory phase is symbolizing as second phase of wound healing which begins
with homeostasis and chemotaxis. This stage begins after the injured vessels or tissue
during the injury start leaking extravascular fluid which further lead to formation of

localized swelling in injured area. This stage usually last for around 7 days where the
actions are being taken to enhance the vascular permeability to limit the damage while
removing the cellular debris and closing of the bound. These actions will foster up the
cellular migration when enhanced mediators and cytokines are being release. After the
initial wounding, in blood vessels the clot is being formed where the vessels dilation
occur after the homeostasis is being achieved. This phase can be identifying with signs
of inflammation including the feeling of heat, pain, edema or functional disturbance in
an injured part. Primarily the phagocyte cells, neutrophils and macrophages work in this
stage.
b. Regeneration
Tissue regeneration or repairing is determined with the closure of the skin wound. Tissues
regeneration is phase when primarily the body replaced the damages tissues which are being
caused due to the injury. Here the regeneration occurs by replicating the identical cells. It is
also known as the proliferation phase where the wound contracts to build a new tissue with the
enriched network of the blood vessels are constructed. It is being done to enhance the sufficient
supply of the oxygen to the cells and tissues in effective manner. Micro-blast cells are
responsible for wound to contract as it results in the closure of the wound. However, the
epithelial cells are responsible for resurfacing the wound and the process is known as the
epithelialization.
c. Maturation
It is symbolize as the final phase of wound healing which his resulted when the wound has
been closed. This phase primarily involves the reconstruct of the collagen from type III to type
I as collagen III are being formed in the proliferate phase of the wound healing. In this phase
the collagen fiber plays the crucial phase as continuously the collagen is produce and
breakdowns to maintain the scar's tissue. They enhanced collagen formation reduce the scar
thickness of the injury which supports the wound area of skin in stronger manner.

Homeostatic control of temperature
1. Using the key choices, select the terms that match the following descriptions
pertaining to body temperature regulation.
Just insert the appropriate letter(s) found to the left of your chosen
answer (see Key Choices) into the answer column. If more than one correct
answer, insert appropriate letters.
Key choices
a. Hypothermia b. Hyperthermia C. Heat
d. Sensory (afferent pathway) e. Thermoreceptors f. Blood
g. Hypothalamus h. Sweating i. Shivering
j. Temperature control centre k. Motor (efferent pathway)
l. Vasoconstriction m. Vasodilation
Heat Produced as a result of cell metabolism
Hypothalamus Thermoregulatory centre
Blood Medium that distributes heat to all the
tissues and carries it to the skin
Temperature control
centre
Site of the body’s temperature control centre
Thermoreceptors Nerves that carry information about
temperature to the hypothalamus (control
centre)
Motor (efferent
pathway) neurons
Nerves convey impulses away from the control
centre and activate the effectors
Sweating Means of liberating excess body heat
Hypothermia Extremely low body temperature
Hyperthermia Extremely high body temperature
Thermoreceptors Receptors that detect temperature
Shivering Generates heat when temperature falls too low
Vasodilation Increases blood flow to the skin
Vasoconstriction Reduces blood flow to the skin

2. Describe the negative feedback loop that will bring about an increase in body
temperature in detail. (Only describe the feedback loop, do not describe how
the effectors increase body temperature).
Negative feedback loops play the important role in regulating the health in the human body.
Negative feedback loop allows the body to regulate itself effectively so it is also known as the
inhibitory loop. It primarily supports the body in regulating the constant level of output as through
them body reduces the enriched level of protein or hormones in the body. It supports the body in
keeping the functioning in stabilized manner while maintaining the equilibrium. It primarily
generates with response to the stimuli. It primarily works in manner to alter the body actions in
opposite manner. Through the nerve endings the signals are been detected about the changes the
body go through which are for examples is accelerated body temperature, these signals are further
pass on to control center present in the brain. These control centers which are present in
hypothalamus regulates the effector to enable their action. Effectors either regulate the shivering or
the narrowing of the blood vessels lead to vasodilation lead to beginning of the sweat to allow more
surface area exposed to cooler external environment. This actions leads to drop in temperature which
cause regain of normal body temperature and to regulate this cooling temperature the body again
regulates for the vasoconstriction. Vasoconstriction will allow more heat which will provide
retention.
3. Temperature regulation: Using the correct words for the negative feedback
mechanism that regulates temperature, enter the main components of the
mechanism on the diagram below and explain the function of each component.
Give examples of specific effectors stating if they increase or decrease body
temperature. Also, insert arrows to indicate the flow of information and label the
pathways.
5 9
10
4 7
1
2
6
3 8

1 – Stimulus produces the changes in variable
2 – Receptors detect the changes
3 – input information is sent along adherent pathway to control center.
4 – Receptor
5 – Afferent pathway
6 – Control center
7 – Efferent pathway
8 – Output information is sent to efferent pathway to the effector
9 – Effector
10 – Response of the effector feeds back to reduce the effect of stimulus and returns the variable to
a homeostatic level.
4. Explain in detail what an ‘effector’ is and give an example of how an effector
works by describing the effects of one effector that cools the body and one
effector that warms the body.
An effector is primarily the part of body which can potentially respond to a stimulus depending upon the
signals which have generated by the body. They are primarily the part of body likely the muscle or gland
which is responsible for producing the response to detect a stimulus. Role of effector is to produce a response
for the muscle squeezing the saliva from salivary gland or assisting the gland to release the hormone into the
blood. From the motor neurone the stimulus is pass to the effector which regulate the response in effective
manner. When the core body temperature reveals to the cool temperature than thermoregulatory effectors
action is seen. Cutaneous vasculature and sweat glands work as the effector which promotes the heat loss
while enhancing the skin blood flow. It is either being occur through the cutaneous vasodilation or by
sweating which occurs from the skin surface to respective air. When the temperature decrease then blood
vessels act as the effector where the vasoconstriction takes place. It results into less blood flow to the skin
surface where the less energy is lost from the body. Hair stand on end to trap the war air which act as the
insulating air and sweating stops.

5. Explain in detail how the body strives to maintain homeostasis.
Homeostasis is symbolizing as the self-regulating process which regulates body internal variables which are
characterized as essential approach to sustain the life. Homeostasis is defined as the body essential
mechanism where the stable internal environment is created to protect body from the external environment.
It is primarily the need of the body to maintain a certain magnitude of equilibrium which takes place inside
mostly without individual having its conscious awareness. To maintain the alteration, occur in body, the
body attempts primarily the two feedback mechanism including the negative mechanism or the positive
mechanism. Negative feedback takes place when change stimulus triggers to alter the changes in reversal
direction and positive feedback occur when response in trigger to enhance the changes in same direction.
The body maintains the homeostasis through temperature, blood glucose or Ph levels. Primarily the body
system is maintained through 3 organs mainly the respiratory system, excretory system and endocrine
system. In respiratory system enhanced concentration of the carbon dioxide in the blood triggers the faster
breathing. It leads to enhanced breathing episodes lead to removal of carbon dioxide more quickly out from
the body. Due to low level of water which is trigger by the kidneys. As it reflects kidney produces more
concentrated form of urine to preserve the water lost form the body in effective manner. In context to the
endocrine system, a high concentration of the sugar in blood triggers insulin secretion through the pancreas.
Every human body contains the internal thermostat when body temperature rises or low than skin and brain
receptors sense the temperature changes where the trigger common is accelerated from the brain. The
response varies depending upon the response. When temperature is hot then skin forms sweat and near the
skin blood vessels dilates to decrease the body temperature.

Multiple choice questions
1. Human beings are able to maintain a certain constancy of their
internal environment. This statement refers to the:
☐ Physiology of the vascular (circulatory) system
☐ Homeostasis in the body
☐ Positive feedback mechanisms work
☐ Direct control of cell activities by nucleus
2.Homeostasis is the condition in which the body maintains:
☐ The lowest possible energy usage
☐ A relatively stable internal environment, within limits
☐ A static state with no deviation from preset points
☐ A changing state, within an unlimited range
3.The two body systems that regulate homeostasis are:
☐ Cardiovascular and respiratory systems
☐ Cardiovascular and endocrine systems
☐ Nervous and cardiovascular systems
☐ Nervous and endocrine systems
4.Which of the following is not the function of the control centre?
☐ It analyses all information it receives
☐ It determines the appropriate actions to take
☐ It sends information to the effector
☐ It sends information to the receptor
5.Which one of the following is not the function of the receptor?
☐ Monitors the environment of the body
☐ Sends information to the control centre
☐ Sends information to the effector
☐ Determine an appropriate action to take
6.Which of the following best describes the function of the effector
☐ It receives information from the receptor and produce a response
☐ It sends information to the control centre
☐ It receives information from the control centre and produce a
response
1.