CH 40 Basic Principles of Animal Form & Function

Some animals have no gills when young, but then develop gills that grow larger as the animal grows larger. What is the reason for this increase in gill size?

Relative to their volume, the young have more surface area across which they can transport all the oxygen they need.

Which of the following is an example of negative feedback?

When the level of glucose in the blood increases, the pancreas produces and releases the hormone insulin. Insulin acts to decrease blood glucose. As blood glucose decreases, the rate of production and release of insulin decreases as blood glucose decreases.

Which of the following animals most likely uses the largest percentage of its energy budget for homeostatic regulation?

a bird living year round in a desert

Most types of communication between cells utilize _____.

chemical or electrical signals

The body tissue that consists largely of material located outside of cells is _____.

connective tissue

Consider the energy budgets for a human, an elephant, a penguin, a mouse, and a snake. The _____ would have the highest total annual energy expenditure, and the _____ would have the highest energy expenditure per unit mass.

elephant; mouse

There are advantages and disadvantages to adaptations. Animals that are endothermic are likely to be at the greatest disadvantage in _____.

environments with variable and limited food sources

Environmental influences appear to contribute to cellular mutations that lead to tumor growth. For example, certain diets lead to higher incidence of colon cancers, and overexposure to sunlight leads to higher incidence of skin cancers. The tissues in closest contact with a carcinogen or mutagen (anything that causes genetic mutations) are obviously the ones most likely to develop tumors. Carcinomas and melanomas account for well over half of all cancers. What type of tissue would you guess the term carcinoma and melanoma is most closely associated with?

epithelial

You are looking through a microscope at a slide of animal tissue and see a single layer of flat, closely packed cells that cover a surface. This specific tissue is most likely _____.

epithelial

Sweating allows a person to lose heat through the process of _____.

evaporation

The panting responses that are observed in overheated birds and mammals dissipate excess heat by _____.

evaporation

In a cool environment, an ectotherm is more likely to survive an extended period of food deprivation than would an equally sized endotherm because the ectotherm _____.

invests little energy in temperature regulation

Blood is best classified as connective tissue because _____.

its cells are separated from each other by an extracellular matrix

Compared with a smaller cell, a larger cell of the same shape has _____.

less surface area per unit of volume

Snake behavior in Wisconsin changes throughout the year. For example, a snake is

more active in summer because it can gain body heat by conduction

As the size of some animals has evolved to greater sizes, the effectiveness of their adaptations that promote exchanges with the environment have also increased. For example, in many larger organisms, evolution has favored lungs and a digestive tract with _____.

more branching or folds

When the body's blood glucose level rises, the pancreas secretes insulin and, as a result, the blood glucose level declines. When the blood glucose level is low, the pancreas secretes glucagon and, as a result, the blood glucose level rises. Such regulation of the blood glucose level is the result of _____.

negative feedback

To prepare flight muscles for use on a cool morning, hawkmoths _____.

rapidly contract and relax these muscles to generate metabolic warmth

An example of an ectothermic organism that has few or no behavioral options when it comes to its ability to adjust its body temperature is a _____.

sea star living deep in the ocean

A moth preparing for flight on a cold morning may warm its flight muscles via _____.

shivering thermogenesis

The cells lining the air sacs in the lungs make up a _____.

simple squamous epithelium

Food moves along the digestive tract as the result of contractions by _____.

smooth muscle

The type of muscle tissue surrounding the intestines and blood vessels is _____.

smooth muscle

Positive feedback differs from negative feedback in that _____.

the positive feedback's effector responses are in the same direction as the initiating stimulus rather than opposite of it

Penguins, seals, and tuna have body forms that permit rapid swimming, because _____.

the shape is a convergent evolutionary solution, which reduces drag while swimming

Hummingbirds are small birds that require a regular food supply. When hummingbirds are faced with a situation that decreases their food supply, such as a storm, which of the following adaptations would be most useful for the bird to survive such an unpredictable and short-term absence of food resources?

torpor

The thin horizontal arrows in the figure above show that the

warmer arterial blood transfers heat to the cooler venous blood

Which of the following would increase the rate of heat exchange between an animal and its environment?

wind blowing across the body surface