What is the zigzag portion called that forms the boundary ends of each sarcomere?
10. What is the zigzag portion called that forms the boundary ends of each sarcomere? The answer is a, Z disc, also called a Z line. The Z disc marks the boundary of each sarcomere and allows for the attachment of actin filaments and titin.
What is the lamella in bone?
The osteocytes are arranged in concentric rings of bone matrix called lamellae (little plates), and their processes run in interconnecting canaliculi. The central Haversian canal, and horizontal canals (perforating/Volkmann’s) canals contain blood vessels and nerves from the periosteum.
What is bone histology?
Histologically, spongy bone is comprised of anastomosing strips of slender bone known as trabeculae that enclose marrow and blood vessels. It forms the relatively softer core of the bones that is filled with marrow.
What is the name of the upper leg bone in the thigh?
The thigh bone, or femur, is the large upper leg bone that connects the lower leg bones (knee joint) to the pelvic bone (hip joint).
What is the functional unit of A skeletal muscle called?
Myofibrils are the basic functional unit of skeletal muscle and are composed of syncytia of multinucleated cells that vary considerably in their biochemical and physiological properties.
What is Z line in muscle?
The Z-band (Z-line, Z-disc) defines the boundary of the sarcomere in striated muscle and bisects the I-band of neighbouring sarcomeres (Fig.
What is spongy bone also called?
Cancellous tissue, also known as cancellous bone, spongy bone or trabecular bone, is characterized by its spongy, porous, honeycomb-like structure and is typically found at the ends of long bones. Compact tissue is also known as hard bone, compact bone or compact cortical bone. Source: GreenFacts.
What is cartilage called?
Overview. The three types of cartilage in your body are hyaline cartilage, elastic cartilage and fibrocartilage.
What are the 4 types of bone?
There are four different types of bone in the human body:
- Long bone – has a long, thin shape.
- Short bone – has a squat, cubed shape.
- Flat bone – has a flattened, broad surface.
- Irregular bone – has a shape that does not conform to the above three types.
What type of tissue is bone?
Bone is made up of compact tissue (the hard, outer layer) and cancellous tissue (the spongy, inner layer that contains red marrow). Bone tissue is maintained by bone-forming cells called osteoblasts and cells that break down bone called osteoclasts.
What is the hardest bone to break?
The femur, or thigh bone, is the toughest bone in the body to break. It’s the largest and thickest bone, for two things, and it’s also protected by all those leg muscles.
What is the weakest bone in the body?
The weakest and softest bone in the human is the clavicle or collar bone. Because it is a tiny bone which runs horizontally across your breastbone & collarbone, it is simple to shatter.
What is another name for skeletal muscle?
skeletal muscle, also called voluntary muscle, in vertebrates, most common of the three types of muscle in the body. Skeletal muscles are attached to bones by tendons, and they produce all the movements of body parts in relation to each other.
What are skeletal muscles made of?
Each skeletal muscle consists of thousands of muscle fibers wrapped together by connective tissue sheaths. The individual bundles of muscle fibers in a skeletal muscle are known as fasciculi. The outermost connective tissue sheath surrounding the entire muscle is known as epimysium.
Is M line thick or thin?
The M line and the Z disc hold the thick and the thin filaments in place, respectively. The elastic filament helps keep the thick filament in the middle between the two Z discs during contraction.
What is M line?
Medical Definition of M line
: a thin dark line across the center of the H zone of a striated muscle fiber. — called also M band.
What is hard bone called?
Compact bone: also known as cortical bone, this hard-outer layer is strong and dense.
What is a mature bone called?
This immature bone is later replaced by secondary or lamellar bone (mature). Secondary bone is further classified as two types: trabecular bone (also called cancellous or spongy bone) and compact bone (also called dense or cortical bone).
What are 3 types of cartilage?
There are three types of cartilage:
- Hyaline – most common, found in the ribs, nose, larynx, trachea. Is a precursor of bone.
- Fibro- is found in invertebral discs, joint capsules, ligaments.
- Elastic – is found in the external ear, epiglottis and larynx.
What are the 3 layers of bone?
- Periosteum – the dense, tough outer shell that contains blood vessels and nerves.
- Compact or dense tissue – the hard, smooth layer that protects the tissue within.
- Spongy or cancellous tissue – the porous, honeycombed material found inside most bones, which allows the bone to be strong yet lightweight.
Which is the smallest bone in human body?
Once there, the sound waves vibrate three bones known as the ossicles, which are made up of the malleus, the incus, and the stapes. The stapes is the smallest bone in the human body.
What is the strongest type of bone tissue?
|Compact||strong, dense tissue found in the shaft of long bones in the arms and legs contains osteons|
|Spongy||less dense, more flexible tissue found in the ends of long bones, pelvis, skull, ribs, spine, and shoulder blades contains trabeculae|
What is the smallest bone called?
The stapes is the smallest bone in the human body.
What bone is broken most often?
The clavicle, more commonly called the “collarbone”, is one of the most frequently fractured bones in the body. In fact, it’s the most common site for a fracture in children. Clavicle fractures can happen to infants during birth as they pass through the birth canal.
Where is skeletal muscle found?
Skeletal muscles are attached to bones by tendons, and they produce all the movements of body parts in relation to each other. Unlike smooth muscle and cardiac muscle, skeletal muscle is under voluntary control.