THE IN-BETWEENERS ◆ ISSUE #04 ◆ SERIES I: THE DENSE DIVISION
Captain Lengthwise
Dense regular connective tissue · he / him
“Pull me. Never twist me.”
POWER: Withstands a bus, pulling in one direction.
WEAKNESS: Pull him sideways and he tears like a paper towel.
FIBERS: Collagen. Almost purely collagenA structural protein in the dermis that provides strength and elasticity., all parallel.
SECRET IDENTITY: The cord you can feel behind your ankle.
Dense regular connective tissue is built for pulling forces in one direction. Every collagen fiber lines up with the pull. That’s the whole trick.
Gym Bro. Only Trains One Direction.
Where he lives, what he does, and the one thing he can’t do
Where he lives
- Tendons: attach skeletal muscle to bone
- Ligaments: attach bone to bone and stabilize joints
- Classic examples: the ACL and MCL of the knee
His powers
- Resists enormous tension along one axisSecond cervical vertebra; has the odontoid process (dens) for pivoting head (“no” motion).
- Parallel collagen lines up perfectly with the direction of pull
His weakness
All that strength runs one way. Load him across the grain, or twist him, and he has nothing.
He’s also poorly supplied with blood, so tendon and ligament injuries heal slowly.
Every weakness is the structure.
Every Single Fiber Agrees With Him
Packed collagen, squeezed cellsThe basic structural and functional units of life., almost no gel
The crew: cells
Fibroblasts make the collagen. It packs so tightly that they (now fibrocytes) get squeezed between the fibers into long, thin rows.
The fibers
Collagen is the main structure: pink, aligned in one uniform direction, with a gentle wave. Some elastic fibers may be present, but collagen dominates.
The matrix
Very little visible ground substance. The tissue is packed tight.
Same Pose in Every Picture
Real slides. Find him in every one.
ID HINT: A pink zebra crossing, with thin dark nucleiClusters of neurons in the CNS responsible for processing information. between the stripes.
Exhibit A
Exhibit B
Exhibit C
Micrographs: University of Michigan Histology, licensed under CC BY-NC-SA 3.0.
Prove You Were Actually Paying Attention
Prove you can spot him
Mission 1: Discover the features of dense regular
Mission 2: The Dense Three quick check
Videos Nobody Asked You to Watch (Watch Them)
Swears He Looks Nothing Like These Two
Students confuse him with these two. Here’s how to tell.
The Basketweaver
Dense irregular. Same packed pink collagen, but running every which way. Lengthwise’s stripes all point the same direction.
The Shock Absorber
Fibrocartilage. Also parallel collagen, but with chondrocytes sitting in lacunae between the bundles. Find a lacunaSmall spaces in bone tissue where osteocytes reside. and it isn’t Lengthwise.
List of terms
- collagen
- axis
- cells
- nuclei
- lacuna