Chapter 42 bio 112 sp 17

At the Society for Neuroscience meeting, among presentations on traumatic brain injury, schizophrenia, and Parkinson's disease, scientists also gather to discuss their research on obesity. Why are these researchers at a neuroscience meeting?

In addition to acting as the integrating center for body temperature, the hypothalamus also regulates appetite.

Which of these animals has the highest metabolic rate per unit body mass?

shrew

Which connective tissue has a fluid matrix?

blood

Where is the nucleus of a neuron found?

cell body

If at the last minute the pitcher decides to throw a curveball, which tissue responds first?

nerve tissue

What are the cells that are specialized to produce and conduct electrochemical impulses called?

neurons

Match each connective tissue cell type to its function.

1. adipose cell stores fat 2. fibroblast secretes collagen 3. macrophage defense against pathogens 4. chondrocyte builds cartilage 5. osteocyte builds bone 6. erythrocyte transports oxygen

Imagine that the tissues of your body each have their own commercials advertising an important function. Match the most appropriate slogan to each tissue type. "We've got the power to move you" "We deliver what you need where you need it" "We keep the good stuff in and the bad stuff out" "We get the message there right away"

1.muscle tissue 2. connective tissue 3.epithelial tissue 4.nerve tissue

Epithelial tissue often functions as an impermeable shield, protecting the body from the outside world. However, in some cases epithelia function to facilitate the directed transport of important substances. Match each set of substances with the transport epithelium that regulates their passage.

1.water, salt, urea 2. amino acids, glucose 3.oxygen, carbon dioxide

After their rapid weight loss, many bariatric surgery patients report that they constantly feel cold. How can you explain this?

Adipose tissue acts as an excellent insulator.

After learning about homeostasis and dynamic constancy, your lab partner says, "I'll have to remember that idea when I weigh myself every day!" Why did she say that?

Although her weight may fluctuate, as long as it stays within a narrow range this does not represent true weight gain.

Which neuronal feature is incorrectly matched with its characteristic?

Axon--carries signals from other cells to the cell body

Which of the following statements about bone and its structure is NOT correct?

Bone tissue is not living because it contains inorganic calcium phosphate crystals.

A friend asks you how exocrine glands differ from endocrine glands. She knows that both form from invaginated epithelium. How do you respond?

Endocrine glands produce hormones which enter the blood stream, while exocrine glands secrete sweat and oil directly to the surface of the skin.

why are epithelial membranes not very thick?

Epithelial tissues play a critical role in transport, and must be thin to allow diffusion to occur.

Select the true statements about connective tissue.

Examples of connective tissue include fat and blood. Cells are generally spaced widely apart. Connective tissue functions to support and connect other structures.

Muscles can carry out their unique motor function because they are the only cells which contain actin and myosin.

False

Which is NOT a feature of muscle cells?

Individual cells are suspended in a matrix.

Select the true statements about Q10.

It usually measures between 2 and 3. It is a measure of temperature. It is a measure of the effect of temperature on a reaction.

Which statement about homeostasis is NOT correct?

Positive feedback mechanisms are common.

Your professor asks you to explain the difference between a tendon and a ligament. How do you answer?

Tendons secure muscles to bones and ligaments secure bones to other bones

Why do some bread recipes suggest letting the dough rise in a warm place after kneading?

The metabolic rate of yeast speeds up at warmer temperatures, so more carbon dioxide is released and the dough rises more quickly.

Which statement describes a home heating and cooling system that functions in a homeostatic way?

The thermostat keeps the temperature within a narrow range.

Connective tissue includes adipose tissue, tendons, bone, cartilage, and blood. What do all these tissues have in common?

They all consist of few cells sparsely distributed in large amounts of extracellular material.

You are hungry and impatient, so you decide to use the oven to speed up the action of the papain enzyme. Which is the best approach?

Warm the oven to 350, then turn it off and put the bowl inside after it has cooled somewhat.

In your Ph.D. research, you use thin slices of brain tissue to study neuronal signaling. You attach an electrode to a single neuron, but cannot detect any activity. What is the most likely explanation?

When you sliced the brain, you disconnected the cell from its dendrites.

A scout troop sets out on a backpacking trip. Soon, an unexpected storm gets them drenched, and the troop leaders discover that few boys have packed warm clothes. Several scouts start shivering uncontrollably, a sign of hypothermia. The leaders call off the trip and the group heads back to their cars. This shivering response was

an attempt to produce heat by burning large amounts of ATP.

Mechanisms that help generate heat and those that allow release of heat are an example of ____________________. Collectively, these mechanisms increase the __________________ of body temperature.

antagonist effectors; stability

If you were the doctor of a patient with ectodermal dysplasia, what activity would you most strongly recommend against?

bikram (hot) yoga

Although especially useful to the giraffe, the rete mirabile is similar to a countercurrent heat exchange system in other related, less evolved, mammals. Thus a mechanism for _________________ homeostasis is likely to have evolved from a mechanism previously used for __________________ homeostasis.

blood pressure; temperature

Integrating Center

brain receives and compares stretch information

A patient has a disease with symptoms in the outer ear, nose, trachea and spine. Which cells are most likely to have a problem?

chondrocytes

Which is NOT a cell or fiber type found in loose connective tissues?

chondrocytes

Which of these is not part of loose connective tissue?

chondroitin

The giraffe, as the tallest living land animal, has several adaptations for its height. To prevent blood from pooling in the head when it bends down to drink, the jugular veins of a giraffe have multiple one-way valves. Furthermore, a web of arteries and veins in the neck called the rete mirabile ("wonderful net") slows the flow of blood into the brain. These specializations of the ______________________ act as mechanisms to maintain ______________________.

circulatory system; blood pressure homeostasis

You are researching a family with a heritable disease whose symptoms include hyper-flexible joints, pliable skin, stretchy ligaments, and fragile muscles that tear easily. You plan to use genetic testing to determine the cause of the disease. Which gene do you sequence first?

collagen

What tissue type produces the tough coverings that package organs?

dense irregular connective tissue

Goblet cell hyperplasia is associated with asthma. Based on their function, what is the likely outcome of an overabundance of goblet cells?

excess mucus production

The thermostat keeps the temperature within a narrow range.

exocrine

Antagonistic effectors are defined as two positive feedback mechanisms that work in the same direction to maintain homeostasis.

false

Neuroglia conduct electrical impulses, passing messages to neurons

false

Stimulus

fetus is pushed against uterine opening

Which of these thermoregulation processes can be sustained for the longest period of time?

hibernation

A year or two after the surgery, temperature regulation often returns to normal. What part of the body has adapted to their new physiology?

hypothalamus

Dogs use panting to dissipate excess heat. What part of their brain detects the need for this response and sends the signal to pant?

hypothalamus

Thermoregulation depends on monitoring of blood temperature. What structure acts as the mammalian temperature sensor?

hypothalamus

Which of these is not a method used by ectotherms to affect body temperature?

increasing metabolic rate

What feature of cardiac muscle helps the cells coordinate their contraction as a single unit?

intercalated disks rich in gap junctions

The most abundant protein in mammals is collagen. This strong, ropelike molecule is particularly abundant in which tissue?

ligaments

Select the true statements about epithelial tissues.

may serve as a covering for structures may serve as a barrier can specialize to form glands classified according to cell shape classified according to the number of layers of cells that are present

When we watch Olympic athletes perform, we are admiring the expert control of which systems working together?

nervous, muscular, and skeletal systems

To diagnose and treat a disease, a doctor must evaluate the patient's body at multiple levels of organization. Identify the level of organization relevant to each stage of the process described below. (1) As part of Fred's annual physical, the doctor examined his skin, fingernails and hair for signs of disease. Noticing an unusual lesion on his neck, the doctor referred Fred to a dermatologist. (2) Upon observing the lesion, the dermatologist said, "Yes, this looks like it could be a squamous cell carcinoma, a tumor in the epidermis of the skin." (3) The dermatologist carefully examined all of Fred's skin for signs of additional tumors, but did not find any. (4) The dermatologist removed the lesion and sent it for a biopsy. Under the microscope, the pathologist saw some cells with abnormal morphology and confirmed a diagnosis of squamous cell carcinoma. However, he noted that the margins of the lesion were clear of abnormal cells, and the tumor had been successfully removed.

organ system, tissue, organ, cell

Which is another name for bone cells that remain alive even after the extracellular matrix becomes hardened with calcium phosphate crystals?

osteocytes

In addition to its presence in desserts, the substance gelatin (derived from collagen) is included in some savory dishes. In the following recipe, which ingredient represents the richest source of collagen? Oxtail Soup water beef flank ox tail or bones mushrooms onions salt black ground pepper sesame oil

ox tail or bones

Effector

pituitary gland secretes oxytocin, which acts on the uterus

Some individuals suffering from extended hypothermia engage in "paradoxical undressing", in which they remove their clothes despite a dangerously low body temperature. One hypothesis to explain this is that their blood vessels dilate from fatigue, creating a false sensation of warmth. Not only does blood vessel dilation release body heat, but removing clothing makes the situation worse. How would you categorize this unfortunate effect?

positive feedback

The symptoms of patients with ectodermal dysplasia may include a complete lack of sweat glands. This is analogous to which of the following problems with your home heating and cooling system?

reduced function of the air conditioning system

Which of these methods of heat transfer is not relevant to biological systems?

reflection

Homeostasis is maintained using negative feedback loops. Which part of a negative feedback loop detects conditions?

sensor

Which type of cells line the lungs and blood vessels?

simple squamous epithelium

Which of the following types of muscles are striated?

skeletal and cardiac

A scientist is trying to coax stem cells to differentiate into muscle to use as a therapy for muscular dystrophy. He looks at his Petri dish and is excited to see the cells contracting! The cells appear striated and multinucleate. What type of muscle are they?

skeletal muscle

Which term refers to muscles that are attached to bones, and cause bones to move at their joints when they contract?

skeletal muscles

When collagen is hydrolyzed it forms gelatin, the main ingredient of a jiggly dessert adored by children. What parts of a cow provide a rich source of collagen?

skin, tendons, and cartilage

in adult vertebrates, which of these is not one of the four principal kinds of primary tissues?

supportive

If the boys progressed into full-blown hypothermia, this would be a failure of which regulatory system?

temperature homeostasis

An evil mastermind has created three new poisons. One interferes with gap junction function, another stimulates sebaceous glands, and a third inhibits goblet cell function. Recently, an unusually high rate of cardiac arrest has plagued the emergency rooms of local hospitals. Which poison is most likely to be responsible?

the poison that blocks gap junctions

After yet another patron dripped sweat on her desk, the clerk at the gym complained, "It's gross working at a gym, with everyone sweating all the time." "Yes," the manager replied, "and it's probably costing us more for ______________, but I'll bet we're saving on _____________________."

the water cooler; air conditioning

To tenderize a tough cut of meat, you soak it in a bowl of papaya juice, which includes the enzyme papain. If a pound of meat needs to soak for one hour at your home in Brazil (27°C), how long will it take to become tender in your chilly Boston apartment (16°C)? (Use the rule of thumb of Q10 = 2 to make your prediction.)

two hours

Select the true statements about an epithelial membrane.

usually one or only a few cell layers thick cover all body surfaces allow some substances through and act as a barrier to other substances