Ch. 40 - Animal Phys

Question 1

What determines ultimate size of a cell?

Answer 1

Surface area to volume ratio

Question 2

What system and who does osteoporosis mostly affect?

Answer 2

Skeletal system and post menopausal women

Question 3

What is emphysema?

Answer 3

Lung disease caused by smoking.

Question 4

Hierarchy order of units in the body

Answer 4

Cells, tissues, organs, and organ systems

Question 5

Hierarchy order of units in the body

Answer 5

Cells, tissues, organs, and organ systems

Question 6

What does the GI tract all entail?

Answer 6

It is an organ system that consists of the stomach, the pancreas, the liver, the intestines, and so on. All the structures from the mouth to the anus.

Question 7

What are tissues?

Answer 7

Make up organs and are composed of specialized cells ( there are 210 different cell types that have been identified in the body, but its actually a lot more) (it ignores several cell systems where we know that the variety of cells is enormous).They can be an array of many different cells with the same genetic information but all working together.

Question 8

What are the five types of tissues?

Answer 8

Epithelial tissue, connective tissue, muscle tissue, and nervous tissue.

Question 9

What is histology?

Answer 9

The study of cells in tissues.

Question 10

What are the four types of epithelial tissue?

Answer 10

Cuboidal epithelial, simple columnar epithelium, simple squamous epithelium, pseudostratified columnar epithelium, and stratified squamous epithelium. Occurring as sheets of cells, they cover the outside of the body and line organs and cavities within the body. Because they are closely packed, often with tight junctions (acts as pretty impermeable glue and form a barrier, sealing be side of the epithelium from the other), they function as a barrier against mechanical injury, pathogens, and fluid loss. Epithelial also form active interfaces with the environment. Ex, the epithelium that lines the nasal passages is crucial for olfaction, the sense of smell.

Question 11

What is stratified squamous epithelium?

Answer 11

Multilayered and regenerates rapidly. New cells formed by division near the basal lamina push outward, replacing cells that are sloughed off. This epithelium is commonly found on surfaces subject to abrasion, such as the outer skin and linings of the mouth, esophagus, anus, and vagina.

Question 12

What is cuboidal epithelium?

Answer 12

With dice shaped cells specialized for secretion, makes up the epithelium of kidney tubules and many glands, including the thyroid gland and salivary glands.

Question 13

What is simple columnar epithelium?

Answer 13

The large, brick shaped cells of simple columnar epithelial are often found where secretion or active absorption is important. For example, a simple columnar epithelium lines the intestines, secreting digestive juices and absorbing nutrients.

Question 14

What is simple squamous epithelium?

Answer 14

The single layer of plate like cells that form a simple squamous epithelium functions in the exchange of material by diffusion. This type of epithelium, which is thin and leaky, lines blood vessels and the air sacs of the lungs, where diffusion of nutrients and gases is critical.

Question 15

What is pseudostratified columnar epithelium?

Answer 15

Consists of a single layer of cells varying in height. In many vertebrates, a pseudostratified epithelium of ciliated cells forms a mucus membrane that lines portions of the respiratory tract. The beating cilia sweep the film of mucus along the surface.

Question 16

Polarity of epithelia

Answer 16

All epithelial are polarized, meaning that they have two different sides. The apical surface faces the lumen (cavity) or outside of the organ and is therefore exposed to fluid or air. Specialized projections often cover this surface. Ex, microvilli, projections that increase the surface area available for absorbing nutrients. The opposite side of each epithelium is the basal surface. The basal surface is attached to a basal lamina, a dense mat of extra cellular matrix that separates the epithelium from the underlying tissue.

Question 17

What are the six types of connective tissue?

Answer 17

Loose connective tissue, fibrous connective tissue, bone, adipose tissue, cartilage, and bone. They all consist of a sparse population of cells scattered through an extra cellular matrix, holding many tissues and organs together and in place. The matrix generally consists of a web of fibers embedded in a liquid, jellylike, or solid foundation. Within the matrix are numerous cells called fibroblasts, which secrete fiber proteins, and macrophages, which engulf foreign particles and any cells debris by phagocytosis.

Question 18

What are the three kinds of connective tissue fibers?

Answer 18

Collagenous fibers provide strength and flexibility, reticular fibers join connective tissue to adjacent tissues, and elastic fibers make tissue elastic. If you pinch a fold of tissue on the back of your hand, the collagenous and reticular fibers prevent the skin from being pulled far from the bone, whereas the elastic fibers restore the skin to its original shape when you release your grip. Different mixtures of fibers and foundation form the major types of connective tissues.

Question 19

What is loose connective tissue?

Answer 19

Connective tissue that is the most widespread connective tissue in the vertebrate body, and it binds epithelial to underlying tissues and holds organs in place. It gets its name from the loose weave of its fibers, which include all three types, it is found in the skin and throughout the body.

Question 20

What is fibrous connective tissue?

Answer 20

Connective tissue that is dense of collagenous fibers. It is found in tendons, which attach muscles to bones, and in ligaments, which connect bones at joints. It is arranged in parallel bundles and is very strong,

Question 21

What are bones?

Answer 21

Connective tissue that the skeleton of most vertebrates is made of. It is a mineralized connective tissue. Bone forming cells called osteoblasts deposit a matrix of collagen. Calcium, magnesium, and phosphate ions combine into a hard mineral within the matrix. The microscopic structure of hard mammalian bone consists of repeating units called osteons. Each osteon has concentric layers of the mineralized matrix, which are deposited around a central canal containing blood vessels and nerves.

Question 22

What are adipose tissue?

Answer 22

Specialized loose connective tissue that stores fat in adipose cells distributed throughout its matrix. Adipose tissue pads and insulates the body and stores fuel as fat molecules. Each adipose cell contains a large fat droplet that swells when fat is stored and shrinks when the body uses that fat as fuel.

Question 23

What is cartilage?

Answer 23

Connective tissue that contains collagenous fibers embedded in a rubbery protein-carbohydrate complex called chondroitin sulfate. Cells called chondrocytes secrete the collagen and chondroitin sulfate, which together make cartilage a strong yet flexible support material. The skeletons of many vertebrate embryos contain cartilage that is replaced by bone as the embryo matures. Cartilage remains in some locations, such as the disks that act as cushions between vertebrate.

Question 24

What is blood?

Answer 24

Connective tissue that has a liquid extra cellular matrix called plasma, which consists of water, salts, and dissolved proteins. Suspended in plasma are erythrocytes ( red blood cells), leukocytes ( white blood cells), and cell fragments called platelets. Red cells carry oxygen, white cells function in defense, and platelets aid in blood clotting.

Question 25

What are the three types of muscle tissue?

Answer 25

Skeletal muscle, smooth muscle, and cardiac muscle. This tissue is responsible for nearly all types of body movement. All muscle cells consist of filaments containing the proteins actin and myosin, which together enable muscles to contract.

Question 26

What is skeletal muscle?

Answer 26

Muscle tissue, that is striated muscle, that is attached to bones by tendons and is responsible for voluntary movements. Skeletal muscle consists of bundles of long cells called muscle fibers. During development, skeletal muscle fibers form by the fusion of many cells, resulting in multiple nuclei in each muscle cell or fiber. The arrangement of contractile units, or sarcomeres, along the fibers give the cells a striped (striated) appearance. In adult mammals, building muscle increases the size but not the number of muscle fibers.

Question 27

What is smooth muscle?

Answer 27

Muscle tissue that lacks striations and is found in the walls of the digestive tract, urinary bladder, arteries, and other internal organs. The cells are spindle shaped. Smooth muscles are responsible for involuntary body activities, such as churning of the stomach and constriction of arteries.

Question 28

What is cardiac muscle?

Answer 28

Muscle tissue that forms the contractile wall of the heart. It is striated like skeletal muscle and has similar contractile properties. Unlike skeletal muscle, however, cardiac muscle has fibers that interconnect via intercalated disks, which relay signals from the cell to cell and help synchronize heart contraction.

Question 29

What does nervous tissue contain?

Answer 29

Neurons and glia. They function in the receipt, processing, and transmission of information. In many animals, a concentration of nervous tissue forms a brain, an information processing center. Nervous tissue contains neurons, or nerve cells, which transmit nerve impulses, as well as support cells called glial cells, or simply glia.

Question 30

What are neurons?

Answer 30

The basic units of the nervous system. A neuron receives nerve impulses from other neurons via its cell body and multiply extensions called dendrites. Neurons transmits impulses to neurons, muscles, or other cells via extensions called axons, which are often bundled together into nerves.

Question 31

What is glia?

Answer 31

The various types of glia help nourish, insulate, and replenish neurons, and in some cases, modulate neuron function.

Question 32

What are hormones and what do they do?

Answer 32

Signaling molecules that broadcast throughout the body by the endocrine system. Different hormones cause distinct effects, and only cells that have receptors for a particular hormone respond. Depending in which cells have receptors for that hormone, the hormone may have an effect in just a single location or in sites throughout the body. They are relatively slow acting. Effects are typically long lasting; hormones remain in blood for seconds, minutes, or even hours.

Question 33

The concept of homeostasis

Answer 33

There are mechanisms in the body which are responsible for maintaining the constancy of various parameters, like internal ph and temperature, both of which stay within very narrow limits.

Question 34

Does homeostasis work by positive or negative feedback?

Answer 34

Negative feedback.

Question 35

How does homeostasis work?

Answer 35

There is a receptor, a detector, that detects changes in the variable being measured, sends a signal to a control center, which then activates a mechanism for reversing the change that has been detected. Ex. ( if the temperature goes down the control center calls for increased metabolism to produce more heat. If it goes down a lot, the control center can turn on another effector like violent shivering to produce even more heat.)

Question 36

Negative feedback processes - overview

Answer 36

They are very important in maintaining the internal constancy of the organism and there are many, many examples. Mostly, these mechanisms are automatic - you don't have to think about taking the next breath, or the next heartbeat, so the nervous system has lots of free time to think about more interesting and important things.

Question 37

Positive feedback - overview

Answer 37

If something goes up, the feedback sends it up even more, so instead of calming things down and restoring the status quo it generates a sort of explosion. (Action potential)