Bio Ch. 32 Mastering Bio

Which of the following statements describes a negative feedback response?

After a meal, blood sugar levels in the body rise; insulin is secreted to lower blood sugar levels. The actions of insulin reverse the internal conditions of high blood sugar levels in the body.

Which of the following actions is not a function of the epithelium?

Allows the internal environment to alter its conditions to match those of the external environment. The epithelium allows the internal environment to remain constant even if the external environment changes.

Which component of a homeostatic system compares sensory information to a target value?

Integrator. An integrator sends instructions to an effector based on sensory information.

Which term describes a steady state in which the internal conditions of an organism are kept within a narrow range without regard to the external conditions?

Regulatory homeostasis. Regulatory homeostasis involves adjusting the internal conditions of an organism to stay within a narrow range without regard to the external conditions.

Which component of a homeostatic system perceives changes in some parameter of the environment?

Sensor. A sensor perceives changes in some parameter of the environment.

Which of the following actions acts to warm a homeothermic body?

Shivering.

_____ muscle is attached to bones.

Skeletal

True or false? Organisms must maintain homeostasis because optimal enzyme activity is achieved within a very narrow range of conditions.

True Enzyme activity depends on conditions within a cell, such as temperature and pH, which must be kept within a certain narrow range.

In a physiological system operating with positive feedback, __________.

a change in a variable will amplify rather than reverse the change A good example of positive feedback is the contraction of the uterus during labor and delivery at the end of pregnancy, in which the response reinforces the stimulus, leading to an even greater response.

Most land-dwelling invertebrates and all of the amphibians

are ectothermic organisms with variable body temperatures.

Which of these is NOT one of the four major categories of tissue?

blood Blood is a type of connective tissue.

An example of a connective tissue is the

blood.

Cardiac muscle is the only muscle composed of _____ fibers.

branched Cardiac muscle fibers are branched.

With its abundance of collagenous fibers, cartilage is an example of

connective tissue

A neuron consists of _____.

dendrites, a cell body, and axons

Negative feedback is a method of homeostatic control that __________.

ensures that conditions in an organism do not vary too much above or below their set points In negative feedback circuits, changes in variables trigger control mechanisms that counteract further changes in the same direction.

Most of the exchange surfaces of multicellular animals are lined with

epithelial tissue.

The nourishment, insulation, and support for neurons are the result of activity by

glial cells.

An example of an organism that has only behavioral controls over its body temperature is the

green frog

The temperature-regulating center of vertebrate animals is located in the

hypothalamus.

All types of muscle tissue have

interactions between actin and myosin.

The four major categories of tissues are __________.

nervous, epithelial, connective, and muscle

Tissues are composed of cells, and tissues functioning together make up

organs.

What type of muscle is responsible for contractions of the digestive tract and arteries?

smooth muscle Smooth muscle is responsible for the involuntary contractions of the digestive tract, arteries, and bladder.

Oxytocin secretion and milk release from the mammary glands of lactating female mammals are initiated by ________

the physical sensation of the baby sucking at the nipple The milk-release response system was given as an example of a neuroendocrine pathway with positive feedback leading to milk release from the nursing mother to the sucking baby. The "neuro" part includes the baby's activation of the mother's mechanoreceptor neurons in the breast.

The absorptive epithelia in the gut are considered "polarized" because

the structures on the apical surface are different than those on the basal surface.

Nervous tissue functions _____.

to sense stimuli