Unit 5 Essential Questions
Lesson 5.1 The Skin
1.What are the functions of skin?
 The skin keeps the outside world out and the body’s organs in. It kills
bacteria with sweat, and maintains water balance. It also helps to maintain
homeostasis. In addition, the skin has receptors for touch, temperature,
and pain.
2.What types of tissue make up the layers of the skin?
 The skin is made up by the epidermis, which is epithelial tissue, and the
dermis, which is the connective tissue.
3.What role do accessory organs such as sweat glands and sebaceous glands play
in the skin?
 The sebaceous glands secrete oils that lubricate the hair follicles so that the
hair can come out. Also, the sweat glands secrete sweat which can cool the
skin, and kill surface bacteria with the pH.
4.What happens to skin as it is exposed to sunlight and as a person ages?
 When skin is exposed to the sunlight, the UV radiation kills some skin cells.
This causes blood to flood the area to try and heal the skin (which is why
the skin turns red) and melanin will also rush to the area to attempt to
repair the damage (which is why the skin tans).
 As a person ages, the epidermis gets gradually thinner. The collaged also
thins out, which causes the skin to wrinkle. The skin starts sagging and
becomes fragile.
5.Which layers of the skin are damaged in different types of burns?
 First degree burns burn through the epidermis. Second degree burns burn
through the dermis. Third degree burns burn through the subcutaneous
tissue. Fourth degree burns burn through muscle and bone.
6.How does burn damage in the skin affect other functions in the body?
 Burn damage will cause the body to reallocate most of its resources to
healing the skin. The body will become prone to infection because of the
wound, and the cardiovascular system and respiratory system would kick
into overdrive to get enough resources in the body to heal itself.
7.How do medical professionals in different fields assist with burn care and
rehabilitation?
 Psychologists would help the patient to cope with trauma, a surgeon would
help with any necessary skin grafting, an anesthesiologist would help with
pain management, and a burn care nurse would help with coordination and
initial burn care.
8.What role does pain play in the human body?
 Pain is a signal to the brain that something the body is doing is dangerous
and is/will cause harm. Pain lets the body know that it needs to stop doing
what it is doing to help prevent serious damage.
9.How does the body interpret and process pain?
 Pain is picked up out of the neurons in the skin layers. This information is
relayed along the spinal cord to the brain and CNS, which is interpreted as
pain.
10.Why would the inability to feel pain actually put the human body in danger?
 One would not be able to realize that they are doing something that is
causing pain to the body. For example, someone could not feel that a stove
was hot, and they would not know to move it to prevent pain.
Lesson 5.2 Bones
1.How does the skeletal system assist with protection in the body?
 The skeletal system provides a strong framework of the body that can resist
blows and keep the body from being damaged.
2.How does the structure of compact bone differ from the structure of spongy
bone?
 Compact bone tissue is very densely packed together, while spongy bone
tissue is loosely packed and less dense.
3.How does the overall structure of bone provide great strength and flexibility,
but keep bone from being too bulky and heavy?
 The compact bone gives bone its strength and durability, while the spongy
bone gives bone its flexibility, and since the whole bone is not dense, it is
lighter weight.
4.What is an X-ray?
 A form of radioactive imaging that is absorbed by hard tissue and appears
white on film.
5.What are the different types of bone fractures and how are they identified on
X-rays?
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Comminuative- Bone broken into 3+ pieces
Transverse- Bone broken at right angle to shaft
Oblique- Bone broken to an angle of the shaft
Greenstick- Bone not completely broken
Compression- Bone crushed
Depression- Bone forced inwards
Spiral- Caused by a torque force/spinning motion.
Open- Breaks skin
Closed- does not break skin
6.How can damage to a bone affect other human body systems?
 Damage to a bone can injure other organs in any body system, cause blood
loss from bleeding, cause an immune response to the injury, interrupt the
endocrine system’s calcium balance, and many other negative things.
7.What is bone remodeling?
 Bone remodeling is a process done by the bone that involves breaking it
down and building it back up so as to keep the bone strong. This also
reshapes the bone after a traumatic injury.
8.How do osteoblasts and osteoclasts assist with bone remodeling and overall
bone homeostasis?
 They break bone down and build bone back up in a stronger and more
appropriately formed way. This helps to keep bones strong.
9.What is the relationship between bone remodeling and blood calcium levels?
 Bone remodeling is a process that involves adding to and taking from the
amounts of blood calcium in the body. This proves helps to maintain
homeostasis.
10.How do hormones assist in the maintenance of healthy bone and the release
of calcium to be used in other body processes?
 Calcitonin and PTH both stimulate osteoblast and osteoclast activity, and
this helps bone to keep being remodeled and strong. Also, this helps to
balance the amount of calcium in the blood.
11.What are the four main stages of healing that occur after a bone fracture?
 Hematoma formation, soft callus formation, bony callus formation, and
bone remodeling.
12.What lifestyle choices relate to the overall strength and protective properties
of bone?
 Eating healthily and intaking enough calcium and vitamin D will keep bones
strong, as well as exercise will help bone keep its strength.
Lesson 5.3 Lymph and Blood Cells
1.What body systems function to protect the human body?
 The immune system, lymphatic system, cardiovascular system,
integumentary system, and others all function to keep the body safe.
2.How does the structure of the lymphatic system relate to its function?
 The thin layers of the lymphatic vessels allow for particles to come in and
out of the lymph with minimal resistance.
3.What is an antigen?
 It is something that goes into the body that can make a person sick.
4.What is an antibody?
 An antibody is something the body produces to recognize and tag an
antigen for destruction.
5.How do circulating antibodies protect a person from receiving incompatible
blood during a transfusion?
 Circulating antibodies realize that the blood that has entered the body is
not safe, and tags it to be destroyed by the other cells.
6.What is specific immunity?
 Specific immunity is when your body recognizes a specific disease or
antigen that has entered the body, and tags the specific antigen for
destruction.
7.What role do lymphocytes play in specific immunity?
 Lymphocytes produce the antibodies that tag the antigens for destruction,
and they also engulf and destroy the antigen.
8.How does your body react the second time it is exposed to a particular antigen?
 The body has memory cells that realize the body is in danger, so lots more
antibodies are produced very rapidly, and these antibodies will help the
body to eliminate the intruder very quickly.