Bag of Bones Trivia Quiz

Answer: Endoskeleton

The endoskeleton exists within the bodies of animals and its purpose is to support the body and enable movement (except for sponges). In vertebrates, the endoskeleton is made of bone and cartilage, while in invertebrates (sponges and echinoderms like starfish) it is made mostly of a calcium carbonate structure.

The exoskeleton is a type of skeleton that develops outside the body (like a shell). Exoskeletons are found in insects, as well as crustaceans such as crabs.

In a hydrostatic skeleton (hydroskeleton) the most important part is the coelom, a fluid-filled cavity which plays a great part in movement and changing shape. Examples of animals with hydroskeletons are earthworms and jellyfish. Eccroskeleton is a made-up term.

Answer: False

Cats have more vertebrae than humans. The types of vertebrae that give them their high mobility are the thoracic (in the chest area) and lumbar (between the ribcage and the pelvis) vertebrae. Cats have thirteen thoracic and seven lumbar vertebrae, while humans have twelve and five respectively. Since cats use their tails for balance in their movements, the tail bones (caudal vertebrae) also contribute to the cats' graceful way of moving. Additionally, cats do not have a collarbone, which allows them to have a longer stride.

Answer: Ulna

The ulna is a long bone that is located in the forearm. It is longer and bigger than the radius, the other long bone found in the forearm. The end of the ulna that is near the elbow (proximal end) is broader than the end near the wrist (distal end), where the ulna narrows down.

Sesamoid bones are embedded within tendons that are in joints. Their purpose is to make the tendons more effective, as well as to protect them. The patella (kneecap) protects the front surface of the knee, and it is the largest sesamoid bone in humans. The cyamella is a small bone in the popliteus muscle that helps rotate the knee. It is rarely found in humans, but it is common in cats and dogs. The pisiform bone is a small bone in the wrist area, where the ulna reaches the wrist.

Answer: Cuckoo

The tailbone is the bone that humans and several other primates have instead of tails. Although its name suggests that it is one bone, it is actually made of several (between three and five) vertebrae that may be fused. The name coccyx comes from the Ancient Greek word for cuckoo, and the tailbone is named so because when it is seen from the side, it looks like a cuckoo's beak.

Coccus is a term used in microbiology for types of bacteria that have a spherical shape (e.g. staphylococcus). It is also used in botany, and it refers to a single seed that is separated from the fruit. Coccus comes from the Greek word for grain or seed.

Answer: Capitate

The ossification (growth) of the wrist bones takes place after birth. The capitate is the first bone to form at approximately two to three months, followed by the hamate almost two months later. The triquetrum is typically ossified at two years, the lunate at five years and the scaphoid at six.

The pisiform is the last wrist bone to form, at approximately twelve years. The wrist bones follow the process of endochondral ossification, in which the ossification happens from the cartilage.

Answer: Osteomyelitis

Osteomyelitis is a disease that causes inflammation of the bone marrow. It is caused by microorganisms that may get to the bones in various ways, including infections and bone replacements. Osteomyelitis can occur to humans as well as dogs.

Panosteitis, Hypertrophic Osteodystrophy (HOD) and Osteochondritis Dissecans (OCD) are diseases that target mainly large breeds of dogs. Panosteitis and HOD are related to the long bones and occur in young dogs. OCD is a disease that affects the joints, when cracks appear in the cartilage surface.

Answer: Distal

There are three bones (distal, intermediate and proximal) in each finger, except the thumb which only has distal and proximal phalanges. The proximal phalanx is first at the base of the finger, followed by the intermediate one. The distal phalanx is at the end of the finger and is typically the smallest, as well as the first to form.

The term phalanges comes from the Phalanx, a formation with rectangular shape used by armies in Ancient Greece.

Answer: Skeletal pneumaticity

Skeletal pneumaticity or pneumatization occurs when there is air in a bone. Most bird species have hollow bones, which makes their skeletons light and more suitable for flying. There are different degrees of pneumaticity, so some birds have more solid bones (e.g. diving birds such as auklets). Bird species that cannot fly, such as penguins, tend to have only solid bones. Skeletal pneumatization is not exclusive to birds.

In humans, skeletal pneumaticity occurs in the paranasal sinuses in the face.

Answer: In the base of the spine

The sacrum is a large bone with a triangular shape. It is located between the bottom lumbar vertebra, known as L5, and the coccyx. The sacrum is also part of the pelvic girdle, where it is in the back between the hip bones. The sacrum is actually made of five vertebrae that fuse in early adulthood. Its name comes from the Latin word for sacred.

Answer: Its dorsal fin is boneless.

Even though they are mammals, dolphins have skeletons with some important differences to those of land mammals. Their forelimbs evolved into flippers, and although they have no fingers, their finger bones (phalanges) are longer and greater in number. Their fins and their flukes are boneless, but unlike fish, dolphins have a pelvis.

They also have rigid necks as a result of their neck vertebrae fusing, which means they usually can only move their necks to the side.