CH 4C

Which is true concerning muscle tissue?

highly cellular and well vascularized

Under a microscope you observe a tissue that appears to have long fibers that appear striated. The nuclei are pushed off to the side of the fibers. The tissue looks very vascular. What type of tissue are you observing?

skeletal muscle tissue The striations are evidence of the myofilaments inside the muscle fibers. The position of the nuclei and vascularity are also signs of muscle tissue.

All muscle cells contain striations

False Smooth muscle cells do not contain striations. Although they do contain myofilaments, their arrangement is not regular enough to generate the striations seen in skeletal or cardiac muscle cells.

Smooth muscle __________.

is under involuntary control Smooth and cardiac muscle are under involuntary control. Skeletal muscle is under voluntary control.

A smooth muscle cell has a central nucleus but lacks striations.

true

Which tissue in the wall of the uterus is required for labor contractions?

Smooth muscle

Intercalated discs and striations are both characteristic of skeletal muscle.

False

Heart muscle cells would tend to separate without ________

intercalated discs

Nervous tissue consists mainly of neurons and collagen fibers

False

Which of the following is NOT a characteristic of nervous tissue?

creates linings Cells that create the body’s linings are all derived from epithelia

Which of the following is a dry membrane exposed to the air?

cutaneous membrane The cutaneous membrane is your skin, an organ consisting of a keratinized stratified squamous epithelium (epidermis) firmly attached to a thick layer of connective tissue (dermis). Unlike other epithelial membranes, the cutaneous membrane is exposed to the air and is a dry membrane.

An infection may occur in a tissue injury. Why?

The increased availability of nutrients allows microorganisms to replicate. The skin and mucous membranes are body’s first line of defense and are mostly impenetrable to microorganisms, unless broken or damaged by tissue injury.

Which of the following statements is INCORRECT?

The cutaneous membrane is made of a simple columnar epithelium The cutaneous membrane, a "dry" membrane exposed to air, consists of a keratinized, stratified squamous epithelium called the epidermis, and an underlying layer of connective tissue called the dermis.

Predict what would happen if a lung’s visceral membrane were pulled away from its parietal membrane still attached to the chest wall.

Loss of membrane adhesive force would cause lung collapse.

Which of the following is NOT a step in tissue repair?

formation of new stem cells

Select the correct statement regarding tissue repair.

Inflammation causes capillaries to dilate and become permeable.

The first step in tissue repair involves ________.

inflammation

Without macrophages, wound healing is delayed. Why?

Macrophages phagocytose many foreign materials, as well as cell debris and dead cells. This cleans the wound, allowing granulation tissue to form.

The correct order of events in tissue repair, from first to last, is __________.

inflammation, organization, and regeneration In order, the basic steps of tissue repair are inflammation, organization, and regeneration

Which event must precede all others during tissue repair?

Inflammation occurs near the affected cells. Inflammation is the first part of the tissue repair. The inflammatory events set the stage for the tissue repair process.

Healing of a surgical incision through the body wall will tend to increase the amount of areolar tissue.

False

Cartilage has good regenerative capacity, while most epithelial tissues do not.

False

Cartilage tissue tends to heal less rapidly than bone tissue.

True

Which tissues have little to no functional regenerative capacity?

cardiac muscle and nervous tissue in the brain and spinal cord Cardiac muscle and the nervous tissue in the brain and spinal cord have virtually no functional regenerative capacity, and they are routinely replaced by scar tissue

After a heart attack, fibrosis occurs at the site of cardiac muscle cell death. This reduces the efficiency of the heart’s pumping activity because __________.

fibrous connective tissue is incapable of contracting Cardiac muscle contains sarcomeres, which allow for the tissue to contract when electrically stimulated. Fibrous connective tissue lacks these special contractile units.