anatomy fall quizes

Flagella are used to move fluids across the surface of the cell.

*false* Cilia are used to move fluids across the surface of their cells. Cells with cilia are anchored in place but may need to propel the fluid around them. Flagella allow a cell to move through its liquid environment. Sperm are the only flagellated cells in the human body.

True or False? Endochondral bone formation stops at birth.

*false* Endochondral bone formation forms most of the bones of your body. The process begins in the embryo when hyaline cartilage "bones" are replaced by osseous tissue. However, the process continues at the epiphyseal plate (growth plate) until adulthood. At the epiphyseal plate a thin line of hyaline cartilage remains and continues to grow through interstitial growth. As new cartilage grows, the epiphysis and diaphysis are pushed further away from each other. The older cartilage on the diaphyseal side of the growth plate is continuously degraded and replaced by bone. In this way the bone grows longer. At fully maturity (18-25 years of age), the hyaline cartilage is completely replaced by bone at the epiphyseal plate and the bone can no longer grow in length.

Small, fat-soluble molecules require transport proteins to cross the cell membrane.

*false* Generally speaking, small uncharged molecules, gasses and fat-soluble molecules can pass through the cell membrane without a channel, carrier or transport protein, as long as they are traveling DOWN their concentration gradient. Ions and larger water soluble molecules require protein channels, carriers or transport proteins to cross the membrane.

Chemical messengers depend on their three-dimensional shapes to bind with cellular receptors. If the structure of the messenger is altered, it will still be able to bind with the cellular receptor.

*false* If a structure is altered, its function will likely be affected as strucutre dictates function.

Cervical vertebrae articulate with ribs.

*false* There are 12 pairs of ribs and they all articulate with the same type of vertebrae... a type of which there are 12... for the 12 pairs of ribs... :)

During transcription, the small and large ribosomal subunits combine to read the mRNA strand and synthesize an polypeptide (amino acid chain).

*false* Translation, not transcription, is the process in which the small and large ribosomal subunits combine to read the mRNA strand and synthesize an polypeptide (amino acid chain). During transcription, an enzyme copies a gene from the DNA on an mRNA molecule.

All organisms must breathe oxygen in order to survive.

*false* While all organisms metabolize to gain energy, not all organisms use oxygen. Even in the human body, there are anaerobic processes which allow us to harvest energy without using oxygen.

Meiosis produces gametes that are genetically identical to the parent cell and are used in reproduction.

*false* although it is true that meiosis produces sex cells for reproduction, the gametes that are produced are not genetically identical to the parent cells. Instead, they contain half the DNA of the parent cell.

Your heart rate (the rate at which it pumps blood) varies depending on your degree of physical activity or neural/hormonal activity. With exercise or fear, heart rate increases to pump more blood to an active body. Yet after exercise, heart rate decreases to a resting level. There are several nerves and hormones that stimulate heart rate to increase as needed, or decrease when needed, but there is no receptor that monitors heart rate. Is heart rate homeostatically regulated?

*no* Homeostatic regulation requires 3 components: a receptor, a control center and an effector. Without a receptor, there cannot be homeostatic regulation. Even though it seems that heart rate varies and returns to some number, this is not technically homeostatic regulation. Blood pressure is homeostatically regulated - it has baroreceptors that monitor pressure, the brainstem that receives the information and nerves that then activate blood vessels to contrict or dilate to correct pressure (as well as other effectors) - but heart rate is not. Heart rate is not monitored by any neuron. Absolute water content of the body is not homeostatically regulated either - no neuron detects the number of water molecules, although neurons do detect the relative saltiness of the body. This is why different people can have the same blood pressure and fluid concentration but very different overall blood volume or heart rate.

Carbohydrates are:

*the preferred energy source most body cells. * Most cells in the human body use glucose as their primary energy source. Molecules are built by dehydration synthesis and broken down by hydrolysis. Enzymes are proteins, made of amino acids, not carbohydrates. In the human body, carbohydrates are stored as glycogen, not cellulose (cellulose is found in plants!).

What time do quizzes become available?

12am

Arrange the following structures in the correct order starting with the simplest level of organization and ending with the most complex. 1. Cell membrane 2. Epithelial cell 3. Human 4. Digestive system 5. Phospholipid 6. Small intestine

5, 1, 2, 6, 4, 3

At rest, why is myosin in the high energy state? (Rest means no AP on the sarcolemma.)

Because the energy in ATP was transferred to the myosin after the ATP caused crossbridge detachment.

After a fracture, what is the correct sequence of repair?

Blood clot, cartilage patch, bony patch, bone remodel

What would happen if your cell membranes did not contain sodium-potassium pumps?

Both of the above would happen if your cell membranes did not contain sodium-potassium pumps.

Keratin is an intracellular protein. How is it made?

By a free ribosome

During a twitch in a skeletal muscle fiber, what is happening in the latent period?

Calcium is flowing through mechanically gated channels

What type of channels in the motor end plate bind Ach (acetylcholine, a neurotransmitter)?

Chemically (ligand) gated sodium channels

Which of the following will least likely reduce movement of the upper limb?

Decreased elasticity of the sacroiliac ligament

Which of the following will increase force production in a skeletal muscle?

Decreasing the time between successive neural stimulations

To be activated, skeletal muscle fibers must receive neurotransmitter from neurons. What structure must neurons penetrate to activate the myofiber?

Endomysium

What structure must neurons penetrate to activate the myofiber?

Endomysium

Which of the following is true regarding biomolecules?

Enzymes are coded for directly by DNA

What type of fluid is found in the transverse tubules (t-tubules)

Extracellular fluid (ECF)

Chemical messengers depend on their three-dimensional shapes to bind with cellular receptors. If the structure of the messenger is altered, it will still be able to bind with the cellular receptor.

False

True or False? You can achieve full range of upper limb motion at the shoulder (flexion, extension, abduction and adduction) only through movements of the glenohumeral joint.

False

The enzyme pepsin is responsible for catalyzing the digestion of food proteins in the stomach. Which of the following conclusions would be most logical?

Food proteins are unable to cross the membranes of digestive cells unless digested.

Where in a sarcomere do you find the thick filament, but not the thin filament?

H-zone

Where in a sarcomere do you find titin and tropomyosin, but not myosin?

I-band

Where do you find the cells that act to remodel or maintain bone?

In all of the listed structures

Which of the following will NOT likely reduce movement of the upper limb?

Increased tightness of the acetabular labrum

Oxygen is essential for cellular respiration and therefore must cross the cell membrane. Which of the following would increase O2 transport into a cell?

Increasing surface area of the cell's membrane

You find a tissue that has the following characteristics: avascular cells contain nuclei, rough ER, golgi apparatuses and mitochondria cells are widely spaced from one another Where did this sample likely come from?

Intervertebral disc

What is the advantage or disadvantage of being a more or less stable joint?

Less stable joints have more range of motion

This figure shows the levels of sex hormones (estrogen and testosterone) from birth to old age. Estrogen in women is the solid purple line; Testosterone in men is the dotted green line. Using this figure, why are men less likely to suffer osteoporosis than women?

Men's adult sustained levels of sex hormone continue to stimulate osteoblasts preventing osteoporosis

Acetylcholinesterase breaks down Ach in the synaptic cleft. What would happen if you somehow increased the amount of acetylcholinesterase (or its activity) in the synaptic cleft?

Muscle contractions would be shorter or may not happen

Which is true?

Myofilaments are proteins

Neurons are specialized for communication. They are capable of sending electrical signals due to the presence of many ion channels and pumps on the cell membrane that they constantly maintain or replace as needed. Which of the following would be NOT consistent with this information?

Neurons are anucleate (they do not have nuclei)

In anatomy, collateral means accessory, subordinate, secondary, serving to support or reinforce. Knowing this, where would you expect to find the tibial collateral ligament?

On the medial aspect of the knee

In anatomy, collateral means adjacent, accessory, secondary, serving to support or reinforce. Knowing this, where would you expect to find the tibial collateral ligament?

On the medial aspect of the knee

According to this figure, what is the primary hormone regulating blood calcium?

Parathyroid hormone (PTH)

Cancers are more common in tissues with high rates of mitotic division. Based on this information, which of the following tissues would be most likely to deveolp cancerous tumors.

Skin epithelium

Sodium (Na+) is more concentrated outside of cells than inside cells. What would happen if the cell membrane permeability to sodium suddenly changed?

Sodium rushes into the cell passively (net inward movement)

Sodium is more concentrated outside of cells than inside cells. What would happen if the cell membrane permeability to sodium suddenly changed?

Sodium rushes into the cell passively (net inward movement)

What is the difference between spongy and compact bone?

Spongy bone and compact bone are microscopically arranged differently

Which of the following would most likely affect your ability to maintain proper blood calcium?

Surgical removal of parathyroid glands, leaving thyroid gland in body

Which of the following is a fibrocartilage cartilaginous joint?

Symphysis

Use this information to help answer the following question: When the suffix -clast is present, it refers to a cell that destroys - for example, a chondroclast is a cell that destroys cartilage. When the suffix -blast is present, it refers to a cell that builds - for example, a chondroblast is a cell that builds cartilage. Now answer: In the normal 30 year old skeleton, osteoclast activity is matched by osteoblast activity. What would happen if osteoclast activity was greater than osteoblast activity?

The bones would become weaker

Suppose you are a cytologist and you are examining an cell under the microscope. You observe that inside the cell there are many flattened, sac-like structures, many of them with small round granules. Based on this information, which of the following conclusions would be most logical?

The cell produces many proteins for export

Which of the following would be most likely found in a cell that is subjected to significant mechanical strain (such as a cell in the outer skin)?

The cell would have many cytoskeletal elements

Apocrine sweat glands, like those in the armpit, produce a watery secretion rich with pheromone oils. Which of the following best describes the cells of these glands that export these secretions?

The cells contain smooth ER and golgi apparatus

In which of the following would you expect to find osteons?

The diaphyseal cortex of the humerus

In bones, a layer of osteoblasts and osteoclasts line the interior of the bone (this cellular layer covers all trabeculae, is adjacent to the medullary cavity and lines the inside of osteons). This layer is called the endosteum. What is its role in bone?

The endosteum can add or remove bone from the inside of bones, remodeling them.

In an infant's humerus, what happens if the rate of hyaline cartilage death is faster than the rate of interstitial growth?

The humerus would become too short at full maturity.

Which are cartilaginous joints? (You may want to use your lecture notes or textbook tables for this one.)

The joint between the pubes and the joint between the bodies of adjacent vertebrae

What is the most inferior articulation between the axial and appendicular skeletons?

The joint between the sacrum and ilium

Which of the following joints allows flexion, extension and slight rotation?

The joint between the tibia & femur

Which are synovial joints?

The joints between true ribs (with the exception of the first) and the sternum

Bisphosphonate medications (like Boniva) result in osteoclast death. Such medications have been prescribed to those at risk of osteoporosis, but after long term use, some people developed mid-shaft femoral fractures. Why?

The medication decreased bone remodeling and microfractures did not heal.

"backbend" this image, which of the following could be described as most inferior?

The plantar surface of the foot

When you swim in a pool, your body gains water. When you swim in the ocean you lose water. What most likely explains these observations?

The pool water is less salty than the inside of your body (and cells); the ocean water is saltier than the inside of your body (and cells)

Which are synovial joints?

The sacroiliac and the joint between the arches of adjacent vertebrae

What happens when parathyroid glands become hyperactive and secrete too much of their hormone?

The skeleton becomes weak

What is the relationship between the muscles crossing a joint and that joint's properties (ie: joint stability, mobility or range and type of motion)? When answering this question, assume muscles are balanced on all sides of the joint.

The stronger the muscles crossing a joint, the more stable the joint

Which of the following joints permits you to shake your head "no"?

The synovial pivot joint between C1 & C2

What is the relationship between the tightness of the ligaments reinforcing joints and that joint's range of motion?

The tighter the ligaments, the less range of motion

What characteristic unites all connective tissue?

They all come from a common embryonic tissue (mesenchyme)

Why do sodium ions enter a cell when gated sodium channels open?

They move down their concentration gradient passively, by diffusion.

Which of the following make up spongy bone?

Trabeculae

Which of the following is a protein that acts to permit the action of another protein?

Troponin

Bad luck! You fall backward and land on your elbow, breaking off the tip. What bone is broken?

Ulna

Why do ions move from low concentration to high concentration?(Against a concentration gradient)

Using cellular energy (ATP)

When you are lying prone on the beach getting a good tan while studying your anatomy textbook, which of the following anatomical structures is considered anterior?

Your navel (umbilicus, belly button)

In vitamin C deficiency you cannot synthesize collagen. Which of the following would most likely occur?

Your skeleton would become malformed

Enzymes:

act on substrates that fit their active site

The muscles that originate at the hyoid and insert on the mandible are ____ of the masseter for jaw movement

antagonists

Endochondral ossification:

begins when osteoblasts are delivered by blood vessels.

The __________ are joined to one another by __________ joints. (You may want to use your lecture notes or textbook tables to help with this one.)

carpals; synovial

During sustained skeletal muscle contractions, crossbridges are:

constantly breaking and reforming asynchronously.

Cells:

have phospholipid membranes which regulate the passage of molecule into their cytosol

The tilting of the sole of the foot medially (inversion) and laterally (eversion) occur through movement at the:

intertarsal joints

During formation of the flat portions of the frontal bone, ______ differentiate to become _______.

mesenchymal cells; osteoblasts Osteoblasts are derived from osteoprogenitor cells which are derived from (differentiate from) mesenchymal cells. Chondroblasts are also derived from mesenchymal cells, but they deposit cartilage, not bone. This process occurs during endochondral bone formation.

Is bone mass homeostatically regulated?

no

During skeletal muscle activation, each myosin requires ____ ATP per cross bridge cycle, and myosin heads cycle ____.

one; as often as possible

What organelle of skeletal muscle cells stores calcium used in muscle contaction?

the sarcoplasmic reticulum

In a muscle cell:

there are many nuclei and the sarcoplasm contains abundant mitochondria

_____ are useful in the skeleton because they remodel most readily in response to stress and efficiently transmit forces while remaining lightweight.

trabeculae

Finish the sentence: I think if a joint is more stable, it will....

will be less likely to dislocate than a similar type, but less stable joint.

As a contracting muscle shortens, the ____ lengthens.

zone of overlap