Lecturexam 2 - lecture exam 2 review PDF

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lecture exam 2 review...

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1) What are the components of the cell membrane and know functions of each

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The phospholipid bilayer serves two major functions. 1. As a container for the cell contents. It separates the cell contents from the surrounding environment. 2. As a police officer to control the movement of molecules into and out of the cell. The interior of the phospholipid bilayer is nonpolar, so only small uncharged molecules like oxygen (O2), carbon dioxide (CO2), and water (H2O) can pass freely through the membrane , either by diffusion or by osmosis.

2) Know the various types of membrane coverings in the body.

3) What is the integumentary system, and its functions? The integumentary system has many functions, most of which are involved in protecting you and regulating your body’s internal functions in a variety of ways:

 

Protects the body's internal living tissues and organs Protects against invasion by infectious organisms

    

Protects the body from dehydration Protects the body against abrupt changes in temperature Helps dispose of waste materials Acts as a receptor for touch, pressure, pain, heat, and cold Stores water and fat

4) What are the three degrees of burns and how you differentiate each?

First-degree. These burns only affect the outer layer of your skin. A mild sunburn’s one example. Your skin may be red and painful, but you won’t have any blisters. Longterm damage is rare. Second-degree. If you have this type of burn, the outer layer of your skin as well the dermis – the layer underneath – has been damaged. Your skin will be bright red, swollen, and may look shiny and wet. You’ll see blisters, and the burn will hurt to the touch.  If you have a superficial second-degree burn, only part of your dermis is damaged. You probably won’t have scarring.  A deep partial thickness burn is more severe. It may leave a scar or cause a permanent change in the color of your skin. Third-degree. Sometimes called a “full thickness burn,” this type of injury destroys two full layers of your skin. Instead of turning red, it may appear black, brown, white or yellow. It won’t hurt because this type of burn damages nerve endings.

5) Know the various cell organelles and functions of each.

Organelle

Function

Nucleus

The “brains” of the cell, the nucleus directs cell activities and contains genetic material called chromosomes made of DNA.

Mitochondria

Make energy out of food

Ribosomes

Make protein

Golgi Apparatus

Make, process and package proteins

Lysosome

Contains digestive enzymes to help break food down

Endoplasmic Reticulum

Called the "intracellular highway" because it is for transporting all sorts of items around the cell.

Vacuole

Used for storage, vacuoles usually contain water or food. (Are you are thirsty? Perhaps your vacuoles need some water!)

Plant cells also have: Chloroplasts

Use sunlight to create food by photosynthesis

Cell Wall

For support

6) Know the functions of keratin, melanin and cerumen.

Strengthens hair Keratin is a major component responsible for strengthening the hair, making it less likely to break.

Coats and repairs damaged hair Keratin helps to smooth and coat frizzy and frayed hair shafts, resulting in smoother and straighter hair. It repairs damaged hair by smoothing and coating the hair shafts and helps to keep in moisture.

Maintains healthy skin Keratin is also contained in the outer epidermis and creates the tough skin in calluses. It helps skin maintain its elasticity and firmness. Keratin controls cell growth and renewal, which helps to soften and control wrinkles.

Skin pigmentation and protection

Keratin has an influence on melanin and skin pigmentation. The protein plays a part in waterproofing skin, according to NaturalSkinHealth.com. It also creates a slight barrier against bacteria and other organisms.

Toughens nails and bony structures Nails are made up of keratin, which causes them to become less prone to chipping and breaking. Keratin is a major part of hardened structures of animals such as horns, hoofs, beaks and even feathers.

Melanin function: Melanin's purpose has nothing to do with human vanity

and everything to do with protecting the organism. UV radiation from the sun is a well-known carcinogen, and in high enough exposures can lead to a number of related types of melanoma, which are malignancies of the skin. Melanomas can be fatal; of the approximately 54,000 Americans diagnosed with a melanoma every year, some 8,000 die from it. The risk of malignant melanoma among people of European ancestry is 10 times that of African-Americans. Cerumen function:

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7) Know the factors that influence the rate of diffusion and how.

8) What are the layers of the epidermis and what happens in each?

The acronym that you can remember to memorize these layers is Come Lets Go Sun Burn

1. Stratum Basale or Basal Layer The deepest layer of the epidermis is called the stratum basale, sometimes called the stratum germinativum. This is where stem cells are located. Because this layer is the

innermost layer, many topical products that you apply to the surface of your skin cannot reach this layer and have an effect. That is why applying stem cells to your skin’s surface is a waste of time – the uppermost layers of the skin prevent large compounds like stem cells from reaching this deep layer. The basal layer is where new skin cells known as “keratinocytes” are “born.” As they are produced, these new cells travel upward, pushing existing older cells even higher in a process known as “keratinization”. Eventually, these skin cells reach the outer layer of your skin, where they push off dead, flaky cells and replace them. This process can take 26-40 days and is affected by age, genetics, hydration and cosmeceutical products. Two other types of cells are also found here: Merkel cells and melanocytes. Merkel cells are receptors that send messages to your brain that get translated as your sense of touch. You have lots of these cells on the palms of your hands and the soles of your feet. Melanocytes produce melanin, which is the pigment that gives your skin and hair their color.

Overactive melanocytes produce too much melanin and can lead to uneven skin pigmentation.

2. Stratum Spinosum or the Spiny layer This layer gives the epidermis its strength. Like its name suggests, the stratum spinosum contains spiny protrusions that hold the cells tightly together to prevent your skin from tearing and blistering.

3. Stratum Granulosum or the Granular Layer This important layer has tiny granules full of components that are produced by skin cells and packaged in the granules. Keratin, which is what gives your strength, is packaged in little keratohyalin granules. Epidermal skin cells are named “keratinocytes” because they produce keratin. The keratinocytes in this layer also produce lipids and natural moisturizing factor (NMF) that make your skin waterproof and help it to hold onto moisture. The lipids, proteins, and natural moisturizing factors are produced in this layer inside “keratohyaline granules.” These granules are produced by the keratinocytes in the granular layer. It’s called the granular layer because of the presence of these granules. In the upper layers of the epidermis (the stratum lucidum and stratum corneum), the granules break open to release their contents into the space between the cells. This bathes the stratum lucidum and the stratum corneum with important lipids that make up the skin barrier and many protective proteins. Overuse of hydroxy acids, retinoids, and other exfoliating ingredients can damage this important layer.

4. Stratum Lucidum The stratum lucidum gets its name from the fact that the granules are no longer there, so the cells look clear or lucid. This thin layer of cells is found only in the thick skin on the palms of your hands and fingers and the soles of your feet.

5. Stratum Corneum This is the outermost layer of the epidermis and is therefore exposed to the atmosphere outside of your body. There are usually 15 to 30 layers of cells in the stratum corneum, which play an important protective role. The cells in this layer help to prevent bacteria, viruses, and fungi from penetrating to deeper layers of skin, as well as provide protection against abrasion and friction for the more delicate underlying layers. This is the layer that makes the skin feel rough when it is dry. The “skin barrier” that prevents evaporation of water is also located here. The entire stratum corneum layer is replaced with new cells in a process known as desquamation. New cells travel up from the basale layer where they are made and push out the old, lackluster cells on the surface. This process usually takes about four weeks. Cosmetic procedures like microdermabrasion smooth the surface of this layer, which makes skin reflect light and look more radiant.

9) Know the various sweat and sebaceous glands of skin and what each secretes and its functions.

11) Know the various types of epithelia and their functions

Eight types of epithelial tissue

First name of tissue indicates number of cell layers o o

Simple—one layer of cells Stratified—more than one layer of cells

Last name of tissue describes shape of cells o o o

Squamous—cells are wider than tall (plate-like) – “squashed” Cuboidal—cells are as wide as tall, like cubes Columnar—cells are taller than they are wide, like columns

In this example we see air sacs of lungs

We find these

types of cells in kidney tubules.

Found in most of the digestive tract, like the stomach

Found in the trachea (just remember cilia pushes mucus up, in the trachea)

Nonke ratinized forms in all places mucous membranes are found

Saliva , sweat and mammary glands all have these cuboidal stratified tissue

Very rare, found in male urethra and large ducts of some glands.

Everyt hing urine-related because it stretches (transitions) with pressure.

12) Know the functions of gap junctions, tight junctions and desmosomes.

13) Know the function of symporters and antiporters.

14) What is a hypertonic vs hypotonic vs isotonic solution, and in which direction would the water move if cell placed in any of those solutions?

15) Know the different types of connective tissue and functions of each?.

Connective tissue is divided into four main categories: 1.

Connective proper

2.

Cartilage

Hyaline cartilage is the most common type and is found in areas such as the trachea, ribs, and nose. Hyaline cartilage is flexible, elastic, and surrounded by a dense membrane called perichondrium. Fibrocartilage is the strongest type of cartilage and composed of hyaline and dense collagen fibers. It is inflexible, tough, and located in areas such as between vertebrae, in some joints, and in heart valves. Fibrocartilage does not have perichondrium. Elastic cartilage contains elastic fibers and is the most flexible type of cartilage. It is found in locations such as the ear and larynx (voice box).

3. Bone

Spongy bone, also called cancellous bone, gets its name because of its spongy appearance. The large spaces, or vascular cavities, in this type of bone tissue contain blood vessels and bone marrow. Spongy bone is the first bone type formed during bone formation and is surrounded by compact bone. Compact bone, or cortical bone, is strong, dense, and forms the hard outer bone surface. Small canals within the tissue allow for the passage of blood vessels and nerves. Mature bone cells, or osteocytes, are found in compact bone

4.

Blood

blood is considered to be a type of connective tissue. Like other connective tissue types, blood is derived from mesoderm, the middle germ layer of developing embryos. Blood also serves to connect other organ systems together by supplying them with nutrients and transporting signal molecules between cells. Plasma is the extracellular matrix of blood with red blood cells, white blood cells, and platelets suspended in the plasma. Connective tissue proper has two subclasses: loose and dense. Loose connective tissue is divided into 1) areolar, 2) adipose, 3) reticular.

 Collagenous fibers are made of collagen and consist of bundles of fibrils that are coils of collagen molecules. These fibers help to strengthen connective tissue.  Elastic fibers are made of the protein elastin and are stretchable. They help to give connective tissue elasticity.  Reticular fibers join connective tissues to other tissues.

Dense connective tissue is divided into 1) dense regular, 2) dense irregular, 3) elastic.

 Dense regular: Tendons and ligaments are examples of dense regular connective tissue.

 Dense irregular: Much of the dermis layer of the skin is composed of dense irregular connective tissue. The membrane capsule surrounding several organs is also dense irregular tissue.  Elastic: These tissues enable stretching in structures such as arteries, vocal cords, the trachea, and bronchial tubes in the lungs.

16) Know the definition of terminal hair, vellus hair, lanugo, erythema, jaundice, cyanosis. Terminal hair: Terminal hair is the thick, long, pigmented hair found on the scalp, face, armpits and pubic area. The growth of terminal hair is influenced by hormones Vellus hair: Vellus hair is short, thin, slight-colored, and barely noticeable hair that develops on most of a person's body during childhood.

Erythema: Erythema (from the Greek erythros, meaning red) is redness of the skin or mucous membranes, caused by hyperemia (increased blood flow) in superficial capillaries. It occurs with any skin injury, infection, or inflammation

Jaundice: Jaundice is a condition in which the skin, whites of the eyes and mucous membranes turn yellow because of a high level of bilirubin, a yellow-orange bile pigment. Jaundice has many causes, including hepatitis, gallstones and tumors Cyanosis: Cyanosis refers to a bluish cast to the skin and mucous membranes. Peripheral cyanosis is when there is a bluish discoloration to your hands or feet. It's usually caused by low oxygen levels in the red blood cells or problems getting oxygenated blood to your body.

17) Know what are the various types of active and passive transport across the plasma membrane and some examples of substances being moved by each

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Simple diffusion – movement of small or lipophilic molecules (e.g. O2, CO2, etc.) Osmosis – movement of water molecules (dependent on solute concentrations) Facilitated diffusion – movement of large or charged molecules via membrane proteins (e.g. ions, sucrose, etc.)

Primary (direct) active transport – Involves the direct use of metabolic energy (e.g. ATP hydrolysis) to mediate transport Secondary (indirect) active transport – Involves coupling the molecule with another moving along an electrochemical gradient...