MCAT Biology › Connective Tissue Types and Properties
What are the four types of tissue?
Muscular, connective, nervous, epithelial
Muscular, cardiac, nervous, sensory
Muscular, dermal, gastric, epithelial
Cardiac, connective, sensory, epithelial
Sensory, connective, nervous, dermal
The four types of tissue are muscular, connective, nervous, and epithelial.
Muscular tissue encompasses skeletal, cardiac, and smooth muscle. Nervous tissue creates the central and peripheral nervous systems (CNS, PNS) and consists of all neurons and glial cells. Epithelial tissue makes up "borders" and lines most organs. Connective tissue generally fills spaces and provides the suspensory matrices for the body, such as bone, fat, blood, and cartilage.
Which of the following is not an example of connective tissue?
Skin
Bone
Adipose
Blood
Skin is composed of epithelial cells, and is therefore not an example of connective tissue. The major types of connective tissue include bone, adipose, blood, and cartilage. Connective tissue is responsible for binding and support of other tissue.
Any tissues can essentially be broken down into epithelium (or endothelium), muscle tissue, neural tissue, or connective tissue.
Which of the following connective tissues serves to link skeletal muscle to bone?
Tendon
Ligament
Cartilage
Adipose
Tendons link skeletal muscle to bone. When skeletal muscle contracts and shortens, the tendon pulls the bone in the direction of the muscle contraction to propel movement.
Ligaments serve to link bone to bone, mainly playing a role in stability rather than force transduction. Cartilage is the main tissue of the ears and nose, and generally provides structure or biological cushioning. Adipose is fat tissue, responsible for storing water and nutrients for extended periods.
Passage:
In a fictional universe, a new life form is discovered that appears to have a number of similarities to humans. Since its discovery by humans, it has been studied with x-ray imaging, magnetic resonance imaging (MRI), computed tomography imaging (CT), as well as with blood chemistries and laboratory studies. Based upon such analyses, scientists have found that both structurally and functionally, this fictional species, called Lorempis marengis, is highly similar to humans. It has structures that appear similar to lungs that are active during respiration. It has a structure that is highly active at all times, especially so in different parts during different activities (similar to the human brain). It also appears to have a digestive tract with a mouth, esophagus, stomach, small intestine, large intestine, and anus that is assumed to carry out the same functions at the cellular level as the parts of the human digestive tract. Scientists are now hoping to continue studying the organism at the cellular level to confirm their assumption that the cellular functions are indeed similar to those of human tissues.
If we assume that the muscle types and cells present in Lorempis marengis are the same, structurally and functionally, as those found in humans, which of the following muscle types best describes the type of muscle cell that lines the walls of most blood vessels?
Smooth muscle
Skeletal muscle
Striated muscle
Cardiac muscle
Biceps muscle
The type of muscle that lines the walls of most blood vessels in the human body is smooth muscle. We are told to make the assumption that the muscle types and cells present in Lorempis marengis are the same, structurally and functionally, as those found in humans. Therefore, the type of muscle that lines the walls of most blood vessels in Lorempis marengis is also smooth muscle. Blood vessels contain a specific subtype of smooth muscle, called vascular smooth muscle, that helps to regulate the distribution of blood volume throughout the entire body by either appropriately contracting or relaxing to restrict or increase blood flow to various parts of the body to best meet bodily needs (typically oxygen delivery).
Skeletal muscle cells, also known as striated muscles, are the type of muscle cells that make up the larger, weight-bearing muscles of the body. These are not the type of muscle cells that are found within the walls of blood vessels. The biceps muscles are the muscles responsible for flexion of the forearm at the elbow. They are not a type of muscle cell, per se, and they are made up of skeletal muscle cells.
Cardiac muscle cells are the type of muscle cells that make up the myocardium, or muscle cells of the heart. These are not the type of muscle cells that are found within the walls of blood vessels.
What are the three types of cartilage?
Elastic cartilage, hyaline cartilage, and fibrocartilage
Maxillary cartilage, formative cartilage, and elastic cartilage
Hyaline cartilage, juvenile cartilage, and maxillary cartilage
Hyaline cartilage, rigid cartilage, and juvenile cartilage
Fibrocartilage, rigid cartilage, and maxillary cartilage
Hyaline cartilage is rigid, glassy in appearance, and provides cushioning for smooth joints. Fibrocartilage is fibrous and provides support in high-stress areas, such as the pubic symphysis. Elastic cartilage is flexible and makes up fleshy appendages, such as the nose and ears.
In what parts of the adult human body would you be most likely to find chondrin?
The ears (pinna) or nose
The skull
Femoral diaphyses
Within haversian canals
Chondrin is the elastic matrix found in cartilaginous connective tissue. In order to identify where chondrin can be found in the body, we should identify where in the body we would find cartilage.
The ears and nose are some of the few structures on the adult human body that contain cartilage. Other cartilage structures include the vertebral discs, public symphysis, menisci in the knees, and most sternocostal joints.
The human skull is formed by intramembranous ossification, a process in which mesenchymal stem cells form osteoblasts and eventually bone. Note that there is no cartilage involved in this process. Long bones, such as the femur, are formed by the process of endochondral ossification, in which cartilage is converted into bone. This process occurs long before adulthood, however, and would not be a reasonable answer in this case. Diaphyses of bones are composed of compact and spongy bone. Haversian canals house blood vessels, nerves, and lymph within bone.
What is the means by which organisms maintain a constant internal environment in spite of fluctuations in the external environment?
Homeostasis
Geriatrics
Homeopathy
Reflexology
Physiology
Homeostasis, or "steady-state" physiology, is the system of feedback loops that enables an organism to create a stable, adaptive environment. For example, the pancreas and the brain together work to regulate the blood sugar levels via the hormones insulin and glucagon.
Which of the following is a type of connective tissue?
Blood
Nerves
Muscles
Skin
Heart
Connective tissues are defined as cells suspended in an expansive extracellular matrix. For blood, plasma serves as the matrix that suspends erythrocytes. Other types of connective tissue include cartilage, bone, and adipose.
Any kind of muscle, nervous, or epithelial cell is in its own category, separate from connective tissue. Skin is a type of epithelium, and the heart is composed of cardiac muscle tissue.
Tendons connect which two structures?
Muscle and bone
Bone and bone
Muscle and muscle
Joint and bone
Fat and fascia
Tendons connect muscles to bones, allowing for the muscle contraction to affect the bone and result in articulation. Tendons are essential to provide articulation and leverage points to for motion and locomotion.
Which of the following is an example of an immovable joint?
Skull sutures
Pubic symphysis
Sacrailium
Phalanges
Tarsal joints
Immovable joints are fused shortly after birth, so that they are no longer functional for articulation. The bones of the skull remain open, joined with strips of cartilage, until an infant has passed through the birth canal. They stay open for a short period, giving the baby's brain room to grow. After the brain has finished its major growth stages, the bones of the skull knit together, forming a protective barrier.