Which outer layer of skin contains pain receptors but lacks blood vessels (causing a shallow cut to hurt without bleeding)?
Epidermis
What is the longest, heaviest, and strongest bone in the human body?
Name the 3 types of muscles
What is Smooth, Cardiac, and Skeletal?
What type of connective tissue directly attaches a skeletal muscle to a bone?
Tendon
What neurotransmitter is released across the neuromuscular junction to initiate a muscle contraction?
Acetylcholine (ACh)
What are two primary functions of the hypodermis (subcutaneous layer)?
Anchoring the skin to muscle, insulating body heat, or absorbing mechanical shock.
Why do newborn babies have significantly more bones than adults?
Bones fuse together during growth. Babies bodies need to travel through the birth canal.
Name two muscles that make up the upper arm?
Biceps
Triceps
Deltoid
etc.
What type of tissue holds bone to bone across a joint to provide stability?
Ligament
Why does physical (mineral) sunscreen protect the skin differently than chemical sunscreen?
Physical sunscreen reflects UV rays away, while chemical sunscreen absorbs UV rays
How do blood vessels in your dermis respond when your body temperature gets too high?
They undergo vasodilation to move warm blood closer to the surface.
The Collar Bone is another name for?
The clavicle
Why must skeletal muscles work in opposing (antagonistic) pairs?
Muscles can only pull (contract) and cannot push.
Which joint type provides the widest range of motion in multiple directions?
Ball and socket joint
Why are third- and fourth-degree deep tissue burns often painless in the immediate affected area?
Sensory nerve endings in the dermal layer have been completely destroyed.
Why does a deep wound in the dermis leave a visible scar, while a surface scratch in the epidermis does not?
During repairs in the dermis, fibroblasts to lay down replacement collagen in a rigid, parallel pattern (and not in the normal woven pattern)
How does the pelvic girdle perform a dual role in the body?
It supports the legs for movement and cradles/protects lower vital organs.
Which two proteins grip and pull past each other to shorten muscle fibers?
Actin and Myosin
What specific joint type sits between the atlas and axis in the neck, allowing you to turn your head side-to-side?
Pivot joint
Why is maintaining a balance of electrolytes like sodium, potassium, and calcium essential during exercise?
They maintain cellular excitability, allowing nerve signals to stimulate muscle contractions and prevent cramps.
How does dark skin help people stay healthy near the Equator? How does light skin help people stay healthy far from the Equator?
Dark skin protects from UV damage and stops folate breakdown (preventing birth defects). Light skin allows for easy vitamin D production from limited UV exposure.
If the intervertebral discs break down, which specific function of the spinal column is most directly impacted?
Shock absorption
What process occurs when a limb is immobilized in a cast for six weeks, and what happens to the muscle tissue?
Atrophy; the muscle shrinks in size and loses strength due to disuse.
The adult skull is held together by non-movable joints. How does this help the skull protect the brain?
Sutures allow for minor movement and shock absorption, protecting the brain from impacts
Why is melanoma considered the most aggressive and dangerous type of skin cancer?
Melanocytes are located near blood vessels in the dermis, allowing cancer cells to metastasize rapidly to other organs.