Quizzes for  Exam 2 A&P I

These questions are to help you quiz yourself. To see my answers, select the area underneath the question using your mouse. (click and drag)  Don't print this out, or the answers will be visible as well!

Chapter 4:
 

A chemical reaction that makes smaller molecules from larger ones, usually with the release of energy is called : catabolism
 What does the body use to make coenzymes, and how much of these substances do we need?
They come from vitamins, and because they are reusable, we don't need very much.
What factors can change the way enzymes function?  Temperature, pH, ion concentration
What is the "energy currency" of the cell? Why? ATP  (adenosine triphosphate). All the chemical reactions in the cell can use ATP as an energy source. If they tried to use a molecule of glucose, for example, they would get much more energy than they needed, and would damage the cell.
Express cellular respiration as a chemical formula. C₆H₁₂O₆ +  6O₂ º 6 CO₂ +6 H₂O

Which one of the four steps of cellular respiration takes place in the cytosol ? Glycolysis
Where do the other 3 steps take place? Inside  mitochondria
What is a Redox reaction?  It is a combination of an oxidation reaction, where a substance loses electrons, and a reduction reaction, where a substance gains electrons. They are always linked inside cells, so that the electrons are passed from one substance to another, and we don't have free electrons running around lose.
What would happen if  NAD⁺ and FAD were not available for cellular respiration? Because these molecules accept electrons from the reactions of glycolysis, formation of acetyl-CoA, and the Krebs cycle and take them to the electron transport chain, none of these reactions would be able to go to completion. There would be nothing for the electron transport chain to work with, the Krebs cycle could only go so far, and we couldn't even run glycolysis by itself, because there would be nowhere for the extra electrons to go. We would be unable to make any energy, and the cell would die.
Where is oxygen used in cellular respiration? As the final electron acceptor in the electron transport chain. It receives two electrons, and two hydrogen ions, and makes water.
 What substance is formed if oxygen is in short supply? NADH puts its electrons onto the end product of  glycolysis, pyruvic acid, and makes lactic acid.

How does the electron transport chain work? The electron transport chain is made up of colorful molecules called cytochromes. They pass high-energy electrons from one to another, becoming reduced, and the oxidized. Every time a cytochrome passes an electron, it takes a little bit of energy from that electron, and uses that energy to push a hydrogen ion  (H+, remember this is really a bare-naked proton!) up a concentration gradient across the inner membranes of the mitochondrion. Now we have a lot of positively charged particles all crammed together in a small space. (Think of all the potential energy stored here, as these particles "want" to get away from each other, but are held in a small space by the membrane !) We let these molecules back down the concentration gradient (electrochemical gradient ) through a  special molecule in the mitochondrial inner membrane that can catch the energy as that H+ or proton falls down. This molecule is called ATP synthase, because it uses the energy of falling H+ to put a phosphate group on ADP to make ATP. Now we are ready to run all the other energy requiring reactions in the cell! This making and using an electrochemical gradient to capture energy is the process of chemiosmosis.
What form does the wasted energy take anytime metabolism occurs? Unfortunately, we are not 100% efficient ( but we are much more efficient than machines, like our cars!). Anytime metabolism occurs and energy is released we can't recapture all of it, and some of it is lost as heat (why your car hood feels warm after you have been out driving). We do make use of this to keep our bodies warm though.
What substances can be broken down to obtain energy by cellular respiration? Remember the taco ? We can use sugars or carbohydrates, lipids and even proteins and nucleic acids as long as we get rid of the nitrogen.
Where do we store the information we need to make things in our cells? What is it we make from this information ? We store this information on our DNA which is found in the nucleus of our cells. On the chromosomes, or large pieces of DNA, are smaller sections, called genes. Each gene carries the information to make proteins. Since enzymes are proteins, we can make enzymes that will make lipids for us, or that can make sugars or nucleic acids. All we  need to make are proteins, and we can do it all !
A group of three nucleic acids that code for a particular amino acid is called a : codon.
What substances make up the "backbone" of DNA and RNA?  Alternating sugar and phosphate groups.
Here is a single strand of  DNA :                           A  C  T  G  C   T  A  C  G  C   T  A
Synthesize the complementary strand of DNA :    T  G  A  C  G  A   T  G  C   G   A  T

Here is a single strand of  DNA :                           C  A  T  G  G  A  T  C  C  A  T  G 
Synthesize the matching strand of mRNA:            G  U   A C  C  U  A  G  G  U  A  C
I am turning pre-messenger RNA into mature mRNA before it leaves the nucleus of the cell to go out into the cytoplasm to find a ribosome to sit on.  To do this, I cut out the introns (intervening sequences) and I splice the exons (expressed sequences) back together.
What is transfer RNA? tRNA is a single strand of RNA that is twisted into the shape of a clover leaf. On the top of the molecule it has an area that carries a specific amino acid. On the bottom it has an anticodon that matches up with a codon on the messenger RNA so that we put the right amino acids together in the right order. This is what you were if you caught one of the pop-beads in in the in class demonstration. If you held your amino acid (Pop-bead) above your head, your anticodon would be found on the bottom of your feet.
Translation means going from the "language" of  nucleotides (DNA and RNA) to the "language" of  protiens - amino acids.
Does a mutation always make a change in a protein? Why not? No, it does not. Remember that a lot of our DNA is "junk", which is really good for identification through DNA fingerprinting, but doesn't code for any proteins. If a mutation occurs here, we won't notice it at all unless we look for it. Remember also, that there are 64 combinations of codons and only 20 amino acids that we use. If we exchange one base, but still code for the same amino acid, that is technically a mutation, but will make no difference in the final protein. If we change an amino acid that does not change the shape of the protein, we will have a slightly different protein that works just fine, or maybe only slightly worse. Remember though, that if we change only one amino acid in the beta chains of the hemoglobin molecule, we get sickle-cell anemia - and that's a big difference!
If I have a mutation that I want to pass on to the next generation, where does it have to occur? The only thing that you will pass on to the next generation is your sex cells or gametes - eggs or sperm. The mutation must be found here to be passed on. If the mutation occurs in a skin cell on your arm, it won't be passed on to the next generation.
Why do we have about 50 enzymes whose job it is to watch our DNA ? These enzymes can often detect problems with the DNA and repair them before the cell reproduces or loses control over cell division.

Chapter 5:
What are the four types of tissue found in your body? Epithelium, connective tissue, muscle tissue and nervous tissue.
What are the two types of epithelial tissue? Covering and lining tissues and glandular tissue.
I have a tissue that has a single layer of cells that are taller than they are wide. It is :  simple columnar epithelium.
I have a tissue that has many layers of cells, and the surface cells are flat. It is: stratified squamous epithelium.
I need a tissue that can resist stretching in only one direction. I should use: dense regular connective tissue.
I need a tissue that can allow substances to pass through by diffusion. I should use: simple squamous epithelium.
I need a tissue that can resist stretching in many directions. I should use: dense irregular connective tissue.
I need a tissue that can protect underlying tissues from abrasion. I should use: stratifed squamous epithelium.
A gland that secretes its products into the tissue fluid and from there into blood is an endocrine gland.
A gland that secretes its product into ducts and then into organs or onto the surface of the body is called and exocrine gland.
A gland whose product consists of the whole cell is called a holocrine gland.
A tissue that has its cells separated by an intercellular matrix would be: Connective tissue
An avascular tissue that has an apical and basal surface and basement membrane would be : epithelial tissue.
The name of a mature cell would end with :  - cyte
The name of an immature cell would end with: -blast
The name of a cell that could break down tissue would end with: -clast
If you had the choice of breaking a bone or tearing cartilage, which should you choose and why?
Go with the bone; it will heal faster and better. Bone has a good blood supply; cartilage has no direct blood supply, so it takes longer for nutrients and oxygen to reach the cells by diffusion. Tendons have only a small blood supply and strains and sprains sometimes take a very long time to heal.
The basic unit of bone is the osteon. In the center is the central canal which contains blood vessels and nerves. Surrounding this are several layers called lamellae. In between each layer are spaces called lacunae where we find osteocytes. These cells are connected to each other by processes they send through the canaliculi which are small channels that connect the lacunae to the central canal.
A neuron has a cell body, and can have many dendrites, but only one axon.

Chapter 6:
I  have several different tissues that work together for a specific function, and that together have a recognizable shape. What do I have? An organ.
What membrane would you find in areas where the outside of the body meets the inside?
Mucous membranes.
What membrane would you find lining joints, and is made only of connective tissue?
Synovial membranes.
Where are the blood vessels in skin? In the dermis and hypodermis. The epidermis, being an epithelial layer, has no blood vessels.
Speaking of blood vessels, I just ran up the stairs and now I'm hot, and I hate to sweat. Is there anything else I can do to cool down? Dilate the capillary beds in the surface layer of skin, and transfer the heat to your surroundings (like a radiator).
So, thermoregulation, protection, vitamin D synthesis, vitamin C synthesis, sense organ activity, blood reservoir,  absorption of water, getting rid of wastes, and absorption of oxygen. Which of these (more than one!) does the skin NOT do? The skin helps make vitamin D but not C; and the skin really only absorbs UV radiation, not water or oxygen, unless of course, you are a frog in disguise!)
I can clearly see five layers of epidermis on my skin slide under the microscope. What kind of skin am I looking at ? I must be looking at thick skin, like in my palms and soles, otherwise I would not easily be able to make out the stratum lucidum.
Since I've got my microscope out, look at these funny cells in the stratum basale. They look like reindeer and have dark granules in them. What are they? Those are melanocytes making melanin.
Some of the cells near the tips of those cells also have the dark granules. How did they get in there?
The keratinocytes (skin cells) took in the melanin from the melanocytes and will use it to protect their nuclei from UVrays. Think of these cells nibbling at the tips of the "reindeer antlers" to get the melanin. This is called cytocrine secretion.
What kind of tissue are we going to find deep in the dermis?
Dense irregular connective tissue - it's tough, and resists stretching in all directions so our skin doesn't rip and fall off.
Look at those bumps or ridges in the upper layer of the dermis, the dermal papillae. What are they for?
They help keep the epidermis anchored to the dermis, so it doesn't slide around. In thick skin, the dermal papillae are tightly anchored to the epidermis, and makes finger prints.
The answer is keratin. What is the question? What protein is found in the epidermis, hair and nails?
Why does my hair stand up when I get cold or scared? The arrector pili muscle contracts and pulls on the bottom of the hair, making it stand out. If we had more hairs, we could trap air this way and make our own sweaters, but who would want to look like that?
I hate it when my palms sweat when I'm nervous. If I go to my dermatologist and ask him to remove the glands that sweat like that, what glands should I ask him to remove? eccrine sudoriferous glands.
While I'm at it, I am tired of spending a fortune on deodorant. Can I have those glands removed too? What are they?  The apocrine sudoriferous glands . Remember that you wouldn't stink if you didn't have bacteria!
What is that white semicircle at the base of my fingernails, and why is it there? That's the lunula. It makes the nail, and the tissue is thicker there so you don't see the underlying capillary bed as well.
I've noticed that my skin is rather yellow lately. What should I check? One, your diet. Have you been eating too many orange vegetables? If not, have your doctor check your liver function; you may have jaundice.
Ouch! I just picked up a hot pot without my oven mitts. Look, it's red and blisters are forming! What have I done?  You have given yourself a second degree burn.
This is not my day. I went to take a shower and only had the hot water on. I managed to scald the entire front of my torso and the entire front of both legs. How much of my body did I burn?
18 (torso) + 9 (front of one leg) + 9 = 36 %