NTR 401 - Final Exam, NTR Final
Hormones in Fasted State
- Glucagon - Epinephrine (catecholamines) - Glucocorticoids (cortisol) - Ghrelin
Glycogen synthase is inhibited by ________, _______ and _______.
- Glucagon - cAMP - Epinephrine
Hormones in Fed State
- Insulin - Gastrin - CCK - Secretin - GLP-1
Roles of protein in the body
- Makes up muscle, skin, organs, blood - Catalysts - Messengers (hormones) - Immunoprotectors - Transporters - Buffers pH in blood - Help regulate fluid balance
Products of b-oxidation:
- NADH - FADH2 - pyruvate
Synthesis of FAs requires ______, _____, _____ & ______.
- NADPH - fatty acid synthase - bicarbonate - CoA
Nutrients in which EAR is defined by function
- Vit B12 (maintaining hematological status) - Choline (Maintain liver function) - Vit E (prevent hydrogen peroxide induced hemolysis) - Riboflavin - Selenium
Which antioxidants work by first trapping and stabilizing a single electron from a free radical?
- Vit C - Vit E - beta-carotene
Nutrients in which EAR is defined by tissue storage
- Vit D (Serum 25-OH cholecalciferol) - Vit B6 (Plasma pyridoxal 5'-phosphate ≥ 20 nmol/L) - Vit A (Adequate liver stores) - Iodine (Thyroid accumulation & turnover) - Magnesium
What components allow phospholipids to associate with water?
- choline - phosphate - inositol
Oxidative pathways of glucose:
- glycolysis - the TCA cycle - electron transport chain (oxidative phosphorylation)
molecules capable of forming stable free radicals
- iron - Vit E - Zinc - beta-carotene - Vit C
What substances are secreted by adipose tissue?
- leptin - adipsin - visfatin
3 active forms of Vitamin A
- retinol - retinal - retinoic acid
What is the average AI for Calcium in adults?
1,000-1,200 mg
Calcitriol is a shorter term for the chemical structure:
1,25 dihydroxycholecalciferol
We obtain Vit D from UV light from the sun converting a form of cholesterol to cholecalciferol in the skin. It is then metabolized to the most biologically active form, which is called ______.
1,25-dihydroxycholecalciferol
Which of the following is the average AI for Calcium in adults? 700 to 900 mg/day 1000 to 1200 mg/day 1300 to 1500 mg/day 400 to 600 mg/day
1000 to 1200 mg/day
In the visual process, rods are responsible for visual processes occurring in dim light by translating objects into black and white images and detecting motion. For visual processes occurring in bright light, cones are responsible and translate objects into color images. This form of Vitamin A binds to the protein opsin to form rhodopsin: A. all-trans-retinol B. 11-cis-retinol C. all-trans-retinyl-ester D. 11-cis-retinal
11-cis-retinal
Which form of Vitamin A binds to the protein opsin to form rhodopsin?
11-cis-retinal
Beta oxidation removes ______ carbons from the fatty acid chain
2
FADH2 creates ___ ATP
2
Glycolysis is the anabolic breakdown of glucose to pyruvate. It produces 2 molecules of pyruvate to every molecule of glucose broken down. It can also be performed in either aerobic or anaerobic conditions. In each set of conditions, pyruvate is either further reduced to lactate (anaerobic conditions) or it is oxidized to acetyl CoA (aerobic conditions). The pyruvate produced in glycolysis leads into the Citric Acid Cycle and the Electron Transport Chain, all which help to produce energy in the form of ATP. How many pyruvate are produced from the breakdown of one molecule of glucose during glycolysis? • 4 Pyruvate • 3 Pyruvate • 1 Pyruvate • 2 Pyruvate
2
In beta oxidation, FADH2 creates _____ ATP
2
What is the recommended period of time that people should sun bathe their hands, feet, arms and face to obtain sufficient Vit D stores?
2-3 times per week for a period of 30-50% of the time it takes to sunburn
How many pyruvate are produced from the breakdown of one molecule of glucose during glycolysis? How many ATP molecules?
2; 4
Pyruvate, the final product of glycolysis, is a vital part of energy flow, as it is contributes to the citric acid cycle and, by default, oxidative phosphorylation. Oxidative phosphorylation produces around 30 molecules of ATP. Pyruvate is formed in glycolysis by the splitting of one hexose sugar (glucose) to two triose sugars (two molecules of pyruvate). 1. How many carbons are in one molecule of pyruvate? a. 2 b. 3 c. 4 d. 5 e. 6
3
The active form of thyroid hormone contains how many iodine atoms?
3
The Sodium-Potassium pump establishes membrane polarity in the cells. This pump is an active transport pump, meaning it requires the use of Adenosine Triphosphate (ATP) to move ions (specifically cations) against their concentration gradient. The polarity established by the Sodium-Potassium pumps plays a large role in nerve conduction, and muscle contraction through neurotransmitter release at the neuromuscular junction. The Sodium potassium pump moves three _________ ions out of the cell, and two _____________ ions into the cell using the hydrolysis of one molecule of ATP.
3 NA out and 2 K+in
What are the 2 main ketone bodies produced via the FA oxidation pathway?
3-hydroxybutyrate & acetoacetate
______ ATP are formed by oxidative phosphorylation
32
The breakdown of glucose by glycolysis and the TCA cycle yields ____ ATP, _____ NADH and ____ FADH2.
4; 10; 2
How many enzymes are needed for the conversion of pyruvate to acetyl-CoA ?
5
During the synthesis of long chain fatty acids, citrate serves as the intermediate transfer of acetyl CoA from the mitochondria to the cytosol; it starts by cleavage of citrate to acetyl CoA. Oxaloacetate is reduced to malate in the cytosol. Oxidation of malate to ________ requires ________ as the hydrogen receptor and generates _________.
????
Water aids in the removal of waste products in the kidney in a process known as urinary excretion. Blood is filtered in the glomerulus, and then the renal tubule reabsorbs some minerals, nutrients, water and ions, while also secreting solutes and waste products into the glomerular filtrate. The reabsorbed substances are then returned to the blood. Q1. What hormone regulates the body's retention of water by increasing reabsorption in the kidney's collecting ducts? A. Vasopressin (ADH) B. Gastrin C. Glucagon D. Leptin
A
While the body retains nutrients that are important for its needs, it also has the ability to excrete unwanted substances. Many of these substances are water soluble and can be removed from the body in the form of urea. The amount of urea that the body puts out is determined by how much sodium, protein, and water a person consumes. The kidneys are responsible for formulating urea by filtering the blood, returning necessary nutrients back to bloodstream, and sending the remaining components to waste. A hormone produced by the pituitary gland, known as ____________, is carried by the bloodstream to the kidneys to be saved and used for regulating water balance in the body. A. ADH B. TSH C. ghrelin D. T4
ADH
The rate of glycolysis is affected by an increase in the activity of ______.
ANYTHING ENDING IN KINASE
During muscle contraction, calcium ions bind to troponin, which exposes the active binding sites on actin. Myosin heads then bind to actin and release ADP and an inorganic phosphate during the power stroke contraction cycle. Once the power stroke is complete, the actin and myosin cross-bridge remains formed. Which molecule is required to bind to the myosin head to detach the cross-bridge and then subsequently hydrolyzes to return the myosin to its resting state? A. Calcium B. ATP C. ADP D. Sodium E. Acetylcholine
ATP
_________ is required to bind to the myosin head to detach the cross-bridge and then subsequently hydrolyze it to return the myosin to its resting state?
ATP
Nutrient-dependent factors recognized to control gene expression include ALL of the following EXCEPT
ATP-magnesium complexes
The metabolic role of vitamin K that links the physiology of bone development and blood clotting is
Adding a second carboxylic acid to a carboxylic acid side chain on glutamic acids in specific proteins.
Nutrients are chemical substances found in foods that are necessary for human life and growth, maintenance, and repair of body tissues. Early scientists began conducting experiments regarding nutrients and came to realize that particular nutrients were "essential" to the diet, some could cause deficiency diseases, and that these nutrients needed to be regulated. There are "conditionally essential" nutrients, proposed by Daniel Rudman, that are not ordinarily required in the diet but which must be supplied to specific populations who can't synthesize them in adequate amounts. There are also "essential" nutrients, which Alfred Harper proposed a list of criteria in order to be considered. These are required in the diet for growth, health and survival, but are not synthesized in the body. Question: Which of the following are considered essential nutrients, according to Alfred Harper? Fatty acids Water Amino acids A and C All the above
All the above
The primary route for excretion of fat soluble compounds from the body is
Along with bile from the liver.
Cellular differentiation is the process of transforming unspecialized cells into specialized ones in different parts of the body. Cell growth is the continuous development of cell tissue and formation. Cellular differentiation depends on a lot of different factors, one mainly being retinoic acid, which is one of the three active forms of vitamin A. Retinoic acid is involved in regulating and expression of genes associated with growth and hormones. Retinoic acid is also essential for embryonic development. The two major receptors for retinoic acid are ________ and ________. One of which forms a heterodimer with Vitamin D and thyroxin receptor.
Answer: RAR and RXR
Aging-related sarcopenia might be reduced by increased levels of ALL of the following EXCEPT:
Ascorbic acid INCLUDES: Leucine, insulin, vitamin D
The concept of measuring protein quality in different foods
Attempts to apply a coefficient to protein quantity in that food that separates the portion of protein that can be used for body functions from that which is used for energy or lost in feces.
After digestion, nutrients are absorbed into the blood or lymph. The small intestine is the major site of nutrient absorption in the human body, but it also can begin in the stomach. Micronutrients consist of water-soluble vitamins, fat-soluble vitamins, and minerals. Water-soluble vitamin absorption, in general, increases when that vitamin is deficient and decreases when it's in excess. Most are absorbed by carrier-mediated mechanisms, with a few exceptions. For example, proteins mediate vitamin B12 absorption and it requires intrinsic factor. Fat soluble-vitamins need bile to be absorbed and are stored in liver and adipose tissues until they're needed. Minerals require specialized carrier proteins in addition to passive and active transport mechanisms to be absorbed by the body. How does the small intestine support nutrient absorption? A. Bile production B. The brush border C. Fermentation D. All of the above
B
In absorption of carbohydrates, glucose and fructose have different rates and methods of transport into the blood stream. Glucose uses SGLT-1 to transport glucose across the wall of the intestine while fructose uses GLUT5 to transport across the wall of the intestine. Due to the different methods, glucose can enter the blood stream at 60 grams per hour, while fructose can do only half of that. This adds to why glucose is the primary source of energy as the body can absorb glucose at a faster rate than fructose. Fructose uses ______ to enter the blood stream A. SGLT 1 B. GLUT 5 C. GLUT1 D. GLUT 2
B
In the cytosol, three Na+ bind to pump proteins. The binding of Na+ triggers the hydrolysis of ATP into ADP, a reaction that also attaches to a phosphate group to the pump protein. This chemical reaction changes the shape of the pump protein, expelling the three Na+ into the extracellular fluid. Now the shape of the protein favors binding of two K+ in the extracellular fluid. Now the pump protein favors binding of two K+ in the extracellular fluid to the pump protein. The binding of K+ triggers release of the phosphate group from the pump protein to change. As the pump protein reverts to its original shape, it releases K+ into the cytosol. At this point the pump is again ready to bind three Na+, and the cycle repeats. The Sodium/Potassium Pump Mechanism takes place in the ________. A. Mitochondria B. Cytosol C. Nucleolus D. Endoplasmic Reticulum
B
There are various functions of Vitamin A including immunity, vision, as well as growth and differentiation of epithelial, nervous, bone and other tissue. All of the following are various functions of Vitamin A except: A. Immunity B. Blood clotting C. Vision D. Growth and differentiation of epithelial, nervous, bone and other tissue
B
What enzyme is used to convert pyruvate to acetyl CoA?
B-pyruvate dehydrogenase
Gluconeogenesis, the 10 step glucose conversion reaction, occurs in the liver. The process of gluconeogenesis is regulated by the hormone insulin that is produced by the ____ in the pancreas. The released insulin then binds to the tyrosine kinase receptors causing them to autophosporylate and activate the PI3K enzyme. A. Alpha cells B. Beta cells C. Gamma cells D. GS subunit
B. Beta cells
The B vitamins are a group of eight water-soluble organic compounds necessary for normal functioning and body maintenance. One major role of the B vitamins is to function as coenzymes in many metabolic reactions. Tetrahydrofolate, the active form of folate (B-9), functions as a coenzyme both in amino acid and nucleotide synthesis. Question 1: A ________ deficiency can lead to a type of anemia which halts normal RBC division resulting in non-functioning and abnormally large RBC's called ___________.
B. Folate; megaloblasts
Inadequate intake of certain vitamins and minerals can cause serious health issues such as damage to the cardiovascular system, nervous system, and muscle tissue. Which of the following is a symptom of Niacin deficiency? A. Muscle wasting B. Dark, scaly skin rash C. Reproductive disorders D. Poor growth of hair and nails
B. Niacin deficiency causes pellagra, which is characterized by symptoms involving the skin, digestive system, and the nervous system.
Tryptophan metabolism uses and generates NAD and NADP, which requires vitamin ______. Tryptophan metabolism yields _________
B6; acetyl-CoA
The region of bone most commonly fractured in individuals with osteoporosis is:
Ball (epiphysis) of the femur
Low intakes of thiamin may lead to which disease?
Beriberi
Pancreatic hormones are critical for regulation of food intake with regards to glucose homeostasis. Insulin is released in a fed state as blood glucose levels rise. Insulin promotes the storage of glucose, as well as the synthesis and storage of lipids and amino acids. Glucagon is a hormone that is released in a fasted state as blood glucose levels decrease. Carbohydrate intake leads to an increase in insulin secretion and a reduction in glucagon secretion. Variations and fluctuations in the levels of these hormones in the body maintain glucose homeostasis. Insulin is secreted by the _____ cells in the pancreas and glucagon is secreted by the ______ cells in the pancreas.
Beta, Alpha
Cholesterol is found in cell membranes. It is also used to synthesize sex and adrenal steroid hormones. Mitochondria convert it from cholesterol to an oxysterol. Cholesterol is also used to make bile acids including cholic acid and chenodeoxycholic acid. This happens through the steroid nucleus modification of cholesterol. Cholic acid and chenodeoxycholic acid are examples of what? A. Bile Acids B. Hydrochloric acids C. Amino Acids
Bile Acids
The latest RDA for vitamin D in men and women is 600 I.U. per day, based upon ______________________ research; however 2000 I.U. per day is an intake that may be more optimum based upon _______________________ .
Bone health; serum 25-OH vitamin D at an optimum value of 75 nmol/L or 30 ng/mL
Three of the most important minerals utilized during healthy bone development are Calcium, Phosphorus, and Magnesium. Bone Remodeling is a concept that highlights the process of breaking down and rebuilding bone. Osteoblast and Osteoclast types of cells found within bone. Osteoblasts secrete specific proteins that provide the support for the bone. Osteoclasts are responsible for breaking down bone. Bone remodeling is not as effective if you exhibit a deficiency in any of the important vitamins and minerals needed to complete the process. For example, a calcium deficiency could lead to an individual developing Osteoporosis. During Bone remodeling, which proteins are secreted by osteoblast cells? Collagen protein matrix Osteocalcin
Both
Membrane creation is heavily reliant on the properties of fat molecules. In order for the membrane to be viable, a lipid bi-layer must form. This is possible because of the amphipathic properties of phospholipids and other Fatty acids. The polar phosphate groups face the water based environment of the cytosol and extra-cellular matrix, while the non-polar carbon chains face inward creating the innards of the cell membrane. Additionally, Cholesterols amphipathic properties allows it to imbed itself within the membrane. While there, cholesterol helps act as a buffer. Meaning: it keeps fluidity up when the environment would encourage rigidity, conversely cholesterol would encourage rigidity when the environment caused fluidity. What role does cholesterol play in membrane stability? a. Increases Rigidity b. Increases Fluidity c. Both Increases and Decreases fluidity depending on the environment d. Cholesterol plays no role in membrane Stability
Both Increases and Decreases fluidity depending on the environment
Vitamin D has many different functions within the body. It is known for it's role in maintaining the proper calcium and phosphorus levels within the body. It is also known for it's role is bone calcification. Recent studies have suggested that Vitamin D helps with immunity, cellular differentiation, and muscle strength. Cancer cells are unable to differentiate and grow very fast. Vitamin D is thought to promote cellular differentiation and inhibit the growth of various cancerous cells. Research has suggested that an individual will decrease their chances of developing which 3 types of cancers when a proper amount of vitamin D is absorbed into the body?
Breast, colon, and prostate cancer
To determine the requirement for a nutrient, nutritionists must measure how much that nutrient is normally needed in the body. Endpoints must be set and an amount of a nutrient is either measured by content or function depending on what role the nutrient plays in the body. Nutrients that can be measured by their content are taken by blood samples to measure a circulating level. Nutrients that are transformed in the body or are stored and not circulated, must be measured by their function. Vitamin D is a nutrient that increases calcium intake, increases calcium stores in the bone, and ultimately increases bone density. Often vitamin D is taken as a supplement in women who are at risk for osteoporosis in hopes to increase their bone density. These women have their bone density tested every one to two years. Given this information, how should the endpoint for vitamin D be determined, by its content or its function?
By it's content - you can easily measure circulating vitamin D in the blood but it takes a very long time to see its effects or function, an increase in bone density.
The primary route for excretion of volatile hydrophobic compounds and gases from the body is
By way of respiratory exchange in the lung.
Regulation of food and nutrient intake by the body is specific to certain nutrients the body requires. In the case of glucose, the body's main source of energy, the body uses homeostatic factors such as hormones to help regulate the amount of glucose available to body tissues in both fasted and fed states. Q1: In the fasted state, which hormone is secreted by the pancreas to increase the availability of glucose in the bloodstream? A: insulin B: ghrelin C: glucagon D: CCK
C
The quality of a protein depends on its digestibility and amino acid composition. Quality can be measured directly, from digestibility and amino acid profile, or indirectly. Typically high quality proteins are of animal origin (e.g., meat) and low quality proteins are of plant origin (e.g., beans and vegetables). Animal proteins have a digestibility of 90-99% while plant proteins have a digestibility of 70-90% due to the presence of protease inhibitors and amylase inhibitors. Which of the following is NOT true regarding protein quality? a) The quality of a protein depends on its digestibility and amino acid composition b) High quality proteins are typically of animal origin c) Animal proteins have a digestibility of 70% d) Protease inhibitors and amylase inhibitors are defense mechanisms against predation
C
Vitamin B-6 has several functions and plays a key role within our bodies. Phosphorylated B-6 plays a role in more than 100 enzymatic reactions; amino acid metabolism, synthesis of serotonin, synthesis of heme, and it decreases the effects of steroid binding hormones. There are many sources of Vitamin B-6, such as meat, poultry, and fish. In addition to being stored within the muscle tissue of animals, B-6 is also found in whole grains. Additional sources include bananas, avocados, raw carrots, etc. The RDA is 1.3 mg/day for men and women ages 19 to 50; at 50 there is an increased requirement, along with a female who is lactating or pregnant (2.0 mg/day). Alcoholics and elderly are the most at risk for deficiency. Which of the following is not a function of Vitamin B-6? A. Synthesis of serotonin B. Decreases effects of steroid binding hormones C. Coenzymes in oxidative reduction reactions D. Synthesis of heme
C
Glucose is broken down through the Catabolic Pathway (Glycolysis) and created through the Anabolic Pathway (Gluconeogenesis). The Catabolic Pathway converts glucose into pyruvate with or without oxygen. You can break down glucose without oxygen through the fermentation process which will produce acetic acid. If you break down glucose with oxygen, glucose is broken down through a two phase process. The first phase being the Preparatory Phase and the second being the Payoff Phase. In the Preparatory Phase, two ATPs are used to break down glucose into 2 three carbon compounds, both containing a phosphate group from the ATP. In the Payoff Phase, each carbon compound is converted to pyruvate. During this process they will each produce two ATPs and a NADH. The Anabolic Pathway creates glucose substrates such as pyruvate, lactate, glycerol and amino acids. This happens through basically reverse Glycolosis with some rate determining steps. Question 1: How many Pyruvate molecules and ATPs are produced when one molecule of Glucose is broken down? A) 1,1 B) 1,2 C) 2,4 D) 4,6
C) 2,4
Protein balance is protein synthesis minus protein degradation. A positive protein balance refers to synthesizing more protein than the amount of protein degraded. A negative protein balance refers to a higher degradation of protein than the synthesis of protein. To be in balance means that the synthesis of protein is equal to the degradation of protein. A healthy adult should be in ____, while a healthy child is should be in____. A) negative protein balance; positive protein balance B) positive protein balance; protein balance C) protein balance; positive protein balance D) positive protein balance; protein balance
C) protein balance; positive protein balance
Cholesterol is needed to make steroid hormones, bile acids and is important for membrane fluidity. Specifically free cholesterol is what serves to aid in steroid hormones and bile salts. Cholesterol is just as essential as total fat. Membrane fluidity can be affected if there is an unbalance in cholesterol such as too little of too much. This can result in a decrease within the fluidity. There are no DRI requirements for cholesterol, which means there is not an EAR. Due to the absence of an EAR there cannot be a RDA. Since there are no dietary requirements for cholesterol what does the DRI lack? A. RDA or EAR B. AI or UL C. A & B D. None of the above
C. A & B
Protein and Ca are two of the main nutrients stored in the muscle. The structural proteins actin and myosin work in conjunction with each other in the process of contraction. A nervous impulse triggers a series of events that results in the release of calcium from the sacroplasmic reticulum. The calcium then allows the heads of the myosin (thick filaments) to bind to the actin (thin filament). The breakdown of ATP is required to supply energy in order to allow the myosin head to continue to move down the actin filament, pulling it inwards and shortening the muscle in contraction. The process of contraction depends upon adequate Ca and ATP stores in the muscle. What protein filaments are the main components of the sliding filament process of contraction in the muscle? Answer: A. ATP and Ca B. Cytokines C. Actin and Myosin D. All of the above
C. Actin and Myosin
According to Harper, the criteria for a nutrient to be considered essential are: Substance is required in diet for growth, health, survival Absence of substance from diet or inadequate intake results in signs of deficiency and disease Growth failure and signs of deficiency are prevented only by the nutrient or a specific precursor to it Below some critical level of intake of the nutrient, growth response and severity signs of deficiency are proportional to amount consumed Substance is not synthesized in the body Of the following, which is NOT considered an essential nutrient: Water B. Iodine C. Biotin D. Iron
C. Biotin
Glucose is the primary fuel source for our body, and there are many different transports that can move glucose into cells. The family of transporters that moves glucose into cells is known as GLUT transporters and they exchange glucose through facilitated transport. Each transporter is given a number between 1 and 12 but the most active ones are 1-7. Out of all of the GLUT transporters only one is insulin dependent and that is GLUT 4. GLUT 4 works is insulin responsive in the skeletal, heart, and adipose tissue; and it is responsible for insulin-stimulated glucose uptake. Which cells are GLUT 4 transporters NOT insulin responsive in? A. Myocytes B. Heart cells C. Enterocytes D. Adipocytes
C. Enterocytes
The body uses carbohydrates as a main source of energy. Glucose is the most important carbohydrate that gets metabolized. Complex carbohydrates must be broken down in the gut to disaccharides or monosaccharides, which, depending on their identity, will feed into the glycolytic pathway at different points. Upon ingesting carbohydrates, the body must respond to the dietary intake accordingly by either using the carbohydrates to provide energy or storing them to be used later. The process of breaking down glucose to release energy is called glycolysis and the process of storing glucose for later use is called glycogenesis. When fructose enters the glycolytic pathway in the liver, it bypasses regulation by the rate limiting step glycolytic enzyme _______________. A. Enolase B. Phosphofructokinase-1 C. Glyceraldehyde-3-P dehydrogenase D. Pyruvate Kinase
C. Glyceraldehyde-3-P dehydrogenase
Under homeostasis conditions the body relies heavily on glucose for fuel. During starvation or a fasting state when glucose is not readily accessible, the body will begin to burn free fatty acids located in the body's fat stores. As an alternative the ketone bodies 3-hydroxybutyrate and acetoacetate are be produced. These ketones produced via the fatty acid oxidation pathway are produced in the ______. A. Gall bladder B. Kidney C. Liver D. Pancreas
C. Liver
Fiber is an important part of a healthy diet. It adds bulk to your diet, makes you feel full faster, and impacts body weight. Which of the following is not true regarding fiber? A. Fiber can be found in whole grain products, legumes, vegetables and fruit B. There is no UL for fiber C. The AI for fiber decreases with age D. Soluble fiber lowers cholesterol, which can help prevent heart disease.
C. The AI for fiber decreases with age
Which of the following is NOT a function of fat soluble vitamins? A. bone growth and development B. vision C. fatty acid synthesis D. blood clotting
C. fatty acid synthesis
Calcium absorption in the small intestine involves the 2 main transport systems, active transport and diffusion. The active transport system in the main transport system for calcium and is saturable and carrier-mediated. What is the binding protein used in calcium absorption that shuttles calcium across the cell cytosol of an enterocyte in order to result in calcium absorption into the plasma?
Calbindin D
The amino acids found in proteins function as structural elements in the body. The contractile proteins actin and myosin are found in cardiac, skeletal, and smooth muscle. Cardiac muscle and smooth muscle are under involuntary control, while skeletal muscle is under voluntary control. Contraction of both skeletal and smooth muscle occurs in response to calcium. Contraction of skeletal and smooth muscle occurs in response to which nutrient? a) Calcium b) Phosphorus c) Magnesium d) Sodium
Calcium
Vitamin K is needed in the diet and can act as a cofactor for a specific enzyme that is used to increase the reaction of carboxylation in glutamic acid. The carboxylation transforms glutamic acid into gamma-carboxyglutamic acid, also known as (Gla). Vitamin K is essential in the diet so that this conversion can take place. This conversion is needed for bone mineralization and blood clotting Which vitamin does vitamin K bind to, to become more active and regulate blood clotting and bone mineralization? Vitamin D Vitamin C Calcium Phosphorus
Calcium
The mitochondrial membrane helps regulate many different metabolic pathways. With regards to lipid metabolisms, its selective permeability regulates both B-Oxidation of Fatty Acids, and Synthesis of Fatty Acids. In B-Oxidation, fatty acids must have the CoA group replaced by a Carnitine in order to cross. Similarly, in order for fatty acid synthesis to occur, acetyl-coA (the precursor to FA synthesis) must be converted to citrate in order to cross. So in summary, the enzymes involved in the conversions of FA and acetyl-CoA into membrane permeable molecules in both of these pathways allow for regulation of the amount of fatty acids created in the cytosol and the amount of fatty acids broken down within the mitochondria. A __________ group must be added to Fatty acids in order to cross the membrane to undergo B oxidation.
Carnitine
Iodide's major role is to produce thyroxine, which is a prehormone. The production of thyroxine is controlled by thyroid stimulating hormone (TSH). Thyroxine is converted to T3 when it is in its target cell. T3 is the active form of thyroxine and controls the rate of cell metabolism. The thyroid gland secretes thyroxine in response to TSH. T3 is important for fetal development. It is essential in brain development and nervous system development. When iodide is deficient in the body, thyroxin is not produced and high levels of TSH result. The thyroid gland increases many biochemical processes, such as cellular growth, and can lead to goiter formation on the thyroid gland. While goiters are usually painless, what negative effect can they have on the body?
Cause difficulty breathing due to pressure on the trachea.
Nutrients are chemical substances found in foods that are necessary for human life and growth, maintenance, and repair of body tissues. Some nutrients are essential, meaning in part that they are required for biochemical functions in the body. Which of the following examples best illustrates essentiality?
Chromium binds to the protein apochromodulin and that complex is needed for full activity of the tyrosine kinase function of the insulin receptor
How does vitamin K get carried to the liver and how does it get carried to the tissues? a. Bile: lymphatic vessels b. HDLs: LDLs c. Chylomicrons: LDLs d. VLDLs: LDLs
Chylomicrons: LDLs
What is the function of pyruvate dehydrogenase? Convert glucose to pyruvate Convert pyruvate to glucose-6-phosphate Convert acetyl CoA to NADH Convert pyruvate to acetyl CoA
Convert pyruvate to acetyl CoA
The EAR or estimated average requirement is the nutrient level required to meet the needs of half the population. By adding 20% or 2 standard deviations this can be converted to the RDA or recommended dietary allowance this accounts for the needs of 97%-98% of the population. The AI or adequate intake is used when an RDA cannot be formulated. The UL or tolerable upper limit is the highest amount of a nutrient that can be taken before there are adverse reactions. Together these factors make up the DRI, daily recommended intake. To ensure adequate vitamin uptake which figure encompasses the largest proportion of the populations needs? A) EAR B) RDA C) UL D) Both A and B E) Both B and C
Correct answer C, taking the tolerable upper limit virtually guarantees adequate supply without detrimental effects if it is the sole source in the diet.
Some nutrients in which certain members of the population cannot synthesize adequate quantities within their own bodies can be classified as conditionally essential. Strong evidence exists supporting the conditional essentiality of Boron and Chromium. Daniel Rudman, who postulated the idea of conditional essentiality, listed these requirements for the nutrient in the event that a nutrient was withheld from the diet. A) Decline in plasma level of the nutrient into the subnormal range B) Appearance of chemical, structural, or functional abnormalities C) Correction of both these by a dietary supplement of the nutrient D) All of the above E) None of the above
Correct answer D - Definition of a conditionally essential nutrient
A dietary supplement that can expand the volume of muscle fibers and aid in providing energy for short term activity is
Creatine
In order to maintain homeostasis and create a response to hunger and satiety hormones, the brain must send the appropriate signal to the target organs as specified by the hormone. Q2: What area of the brain is targeted by hormones in order to produce a response to hunger or satiety? A: frontal lobe B: cerebellum C: pituitary gland D: arcuate hypothalamus
D
Vitamins and minerals play a major role in the production of bone with hormones controlling the storage of these vitamins/minerals. Bone goes through cycles of breaking down (osteoclast cells) and building up (osteoblast cells). In order for bones to be strong, they must have a good collagen protein matrix formation. Vitamin ___ promotes the absorption of calcium and helps strengthen bones and prevent osteoporosis.
D
Biogenic amines and neurotransmitters/hormones are important in the human body as they act on neurons and muscles. The uptake of tryptophan and tyrosine act as precursors for several hormones and/or neurotransmitters. Tryptophan, in particular, is used in: A. The synthesis of melatonin and serotonin B. Synthesis and release correspond with darkness C. Involved in regulation of circadian rhythms and sleep D. All of the above
D. All of the above
There is plentiful research supporting the consumption of omega-3 fatty acids. Supplementation of them in the diet, typically from fish oil or sometimes flax oil, can have benefits ranging from decreased risk of atherosclerosis to improved cognition. Standard American diets often lack adequate amounts of omega-3 fatty acids (and often pair that with an excess of omega-6), and with high rates of cardiovascular disease and dementia with age, there is much focus on improving the fatty acid profiles of peoples' diets. However, these benefits are often tied to one specific omega-3 fatty acid. Which omega-3 fatty acid is associated with antithrombotic (reduces formation of blood clots) and anti-inflammatory actions? A. Inositol phosphoglyceric acid (IPA) B. Docosehexaenoic acid (DHA) C. Alpha linoleic acid (ALA) D. Eicosepentaenoic acid (EPA)
D. EPA
Glycogen metabolism is an important process for proper bodily function. The regulation of glycogen metabolism is also very important. Glycogen stores can be built up when blood-glucose levels are high and degraded when blood-glucose levels are low. Insulin, glucagon, and epinephrine are a few examples of factors that regulate the enzymes responsible for the catabolism and anabolism of glycogen. Glycogen synthase, the rate-limiting enzyme in glycogenesis, is inhibited by all of the following except ____________. A. Glucagon B. cAMP C. Epinephrine D. Glucose-6-Phosphate
D. Glucose-6-Phosphate
Glycogen metabolism is an important process for proper bodily function. The regulation of glycogen metabolism is also very important. Glycogen stores can be built up when blood-glucose levels are high and degraded when blood-glucose levels are low. Insulin, glucagon, and epinephrine are a few examples of factors that regulate the enzymes responsible for the catabolism and anabolism of glycogen. Question 2: Glycogen synthase, the rate-limiting enzyme in glycogenesis, is inhibited by all of the following except ____________. A. Glucagon B. cAMP C. Epinephrine D. Glucose-6-Phosphate
D. Glucose-6-Phosphate
Vitamin E mainly plays the role of an antioxidant in the body; it is able to prevent the oxidation of unsaturated fatty acids that are found in the phospholipid membranes of cells by preventing the propagation of free radicals through chain breaking. Because of this Vitamin E is typically found in cell membranes throughout the body, and there is no main storage organ for it. As a fat soluble vitamin the greatest amount of Vitamin E is found in the adipose tissue. The concentration found in the adipose tissue depends upon the dose of Vitamin E but release from these tissues is slow. Which fat-soluble vitamin plays a large role in anti-oxidant protection of cell membranes and other body components? Answer: A. Vitamin A, B. Vitamin K, C. Vitamin D, D. Vitamin E.
D. Vitamin E.
• β-OXIDATION is an important catabolic pathway of lipid. • It involves oxidation, hydration, oxidation, and cleavage and continues until all of the CoA substrate has been converted to acetyl CoA. • The enzymes involved in the pathway include acyl CoA dehydrogenase, enoyl CoA hydrates, dehydrogenase (specific of the type of isomer) and 3-ketothiolase. Q1: Which of the enzyme is not involved in ß-OXIDATION? A. acyl CoA dehydrogenase B. enoyl CoA hydratase C. 3-ketothiolase D. acyl-CoA carboxylase
D. acyl-CoA carboxylase Acetyl-CoA Carboxylase, which converts acetyl-CoA to malonyl-CoA, is the committed step of the fatty acid synthesis pathway!
The process of moving sodium and potassium ions across the cell membrane is an active transport process involving the hydrolysis of ATP to provide the necessary energy. It involves an enzyme referred to as Na+/K+-ATPase. This process is responsible for maintaining a large excess of Sodium outside the cell and the large excess of potassium ions on the inside of the cell. The cycle of the transport process accomplishes the transport of three Na+ to the outside of the cell and the transport of two K+ ions to the inside. This pump is an important contribution to the action potential produced by nerve cells. The channels in the sodium potassium pump open in response to _____________ in transmembrane voltage. A. Depolarization B. Repolarization C. Hyperpolarization D. Afterhyperpolarization
Depolarization
Calcium is needed by every cell in the human body, and about 99% of it is found as a structural component for our bones and teeth. Some promoters of calcium absorption are vitamin D, gastric acid, lactose, citrate and malate, protein, phosphorus, and exercise. Some calcium absorption inhibitors are oxalic acid, phytic acid, dietary fiber, phosphate, steatorrhea, and an increased rate of passage. Phytic acid is only found in plant-derived foods. Why might a vegetarian be at risk for calcium deficiency?
Due to their diet, vegetarians would typically take in more physic acid and possibly less protein than non-vegetarians.
Proteins are necessary for human life. They have many functions in the body such as catalysts, messengers, structural elements, immunoprotectors, transporters, buffers, and fluid balance. As catalysts, proteins are enzymes that sped up the rate of chemical processes. As messengers, proteins are hormones that control the certain functions in cells. In muscle, myosin and actin are contractile proteins. Immunoglobulins IgG, IgA, IgM, IgE, and IgD are immunoprotectors. Uniporters, symporters, and antiporters are various transporters that are protein. Proteins are capable of giving up an electron to an acid to act as a buffer. The presence of proteins attracts water and contributes to osmotic pressure. Which of the following are function(s) of proteins: A) transportation B) signaling C) structural D) catalytic E) all of the above
E
Which one of these is NOT used to create glucose? A) pyruvate B) lactate C) glycerol D) amino acids E) All of these can be used
E) All of these can be used
Dietary guidelines, or DRI's, have been set in place to standardize and regulate the way we are able to measure nutrition adequacy. DRI's can be used for planning and assessing the diets of individuals and groups. They are especially important in understanding at what level a nutrient can cause adverse or toxic effects. Each of these reference values under the DRI's are used as recommended daily nutrient intakes for various groups of the population: Estimated Average Requirement (EAR), Recommended Dietary Allowance (RDA), Adequate Intake (AI), Tolerable Upper Intake Level (UL), and Acceptable Macronutrient Distribution Range (AMDR). These guidelines are applied to healthy individuals, but are not designed specifically for an individual person due to variance in reference height and weight. Question: The DRI Guideline that meets the nutrient intake needs of half the healthy individuals is? RDA UL AI EAR
EAR
Our body mainly uses what molecule to make anti-inflammatory PGE-3 and LTB-5 molecules?
EPA
Polyunsaturated fats such as linolenic acid and linoleic acid are required for animals for proper growth and function. These fatty acids are considered essential as they cannot be made within the body. Linoleic acid is utilized by the body to make arachidonic acid which can then be converted to make pro-inflammatory molecules. This fatty acid can be found in corn oil and sunflower oil. Linolenic acid on the other hand can be converted to EPA and DHA. EPA can then be converted to anti-inflammatory molecules. Linolenic acid can be found in soybean oil. Our body mainly uses what molecule to make anti-inflammatory PGE3 and LTB5 molecules? a. DHA b. EPA c. Arachidonic acid d. GLA
EPA
Vitamin D is associated with skeletal growth and strong bones. It is extremely important for children to ingest an adequate amount of vitamin D to develop strong bones and healthy teeth. Vitamin D works by increasing the amount of calcium absorbed and aids to form and maintain bones. Vitamin D is a group of fat-soluble steroids and has several different forms. Two forms are the most important in humans. Vitamin D2 or _______________ is found in certain plants and is chemically synthesized. _______________ or cholecalciferol is synthesized by animals and found in animal-based foods.
Ergocalciferol, D3
The hormone (street name) that has been used in competitive athletes (usually illegally) to increase the concentration of red blood cells because of its action on bone marrow cells is
Erythropoietin (EPO)
The DRI was developed as a means to replace the old singular method, which focused on large populations, RDA to provide various methods of measuring nutritional adequacy. The DRI groups nutrients together based on their physiological functions in the body, and suggest markers of deficiency, toxicity, chronic disease endpoints, and suggest recommendations for both essential and nonessential nutrients. Q. The DRI is made up of the following systems of measurement: a. RDA b. EAR c. AMDR d. AI e. UL f. all of the above
F
There is a Tolerable Upper Intake Level (UL) established for protein.
False
Water-soluble vitamins are dissolved in water and are never stored in the body. If there is an excess amount of a water-soluble vitamin, it will be excreted from the body through urine. With this in mind, we need to keep a constant intake of water soluble vitamins in order to maintain a healthy amount in our bodies. Vitamin C and B-complex Vitamins are water soluble. Since B-complex vitamins are water soluble, we do not need to worry about how much of these vitamins we consume.
False
A high intake of water-soluble vitamins can become toxic.
False. Because water-soluble vitamins are not stored in the body, any amount taken in excess will be excreted by urination.
Amino acids are used in the body when diets are inadequate in protein. Amino Acid Catabolism can be used to produce energy, glucose, ketone bodies, cholesterol, and ___________
Fatty Acids
is the compound that is necessary to avoid neural tube defects in developing infants.
Folate
Polyglutamate hydrolase is a zinc dependent enzyme in the GI tract that is involved in the proper absorption of
Folic Acid
Glucagon binds to ___________ on hepatocytes
G-protein coupled receptors (GPCRs)
Both glucagon and epinephrine have signal receptors on what proteins?
G3P
The illeal brake phenomenon slows the movement of fluid from the upper small intestine down to the ileum through a feedback system. It controls the rate of flow of the meal to absorptive sites. What hormone interacts with and helps regulate the illeal brake phenomenon? Leptin GLP-1 CCK Ghrelin
GLP-1
What hormone interacts with and helps regulate the ileal brake phenomenon?
GLP-1
Which group of steroid hormones are released when blood glucose levels are low to encourage glycogenolysis?
GLUCOCORTICOID: CORTISOL
Of the GLUT transporters, which is insulin-dependent?
GLUT-4
Fructose uses ______ to enter the blood stream
GLUT-5
The family of transporters that moves glucose into cells is known as _______ transporters and they exchange glucose through _____________
GLUT; facilitated transport
Keeping an appropriate quantity of sodium in the blood, sodium concentration in the blood, and blood pressure involves ALL of the following hormonal systems and organs EXCEPT
Gastrin blockage of sodium absorption in the colon.
The endocrine system is important in regulating homeostasis through hormone release, transport, and feedback mechanisms. Certain hormone levels are elevated depending on if the body is in a fasted versus a fed state. Which of the following hormones are NOT elevated in a fed state? Insulin Gastrin CCK Ghrelin
Gherkin
When the body regulates food intake, it is trying to maintain homeostasis. So, when a person eats a meal, they begin to feel full when satiety signals are sent out through the blood stream and interpreted in the brain, which tells them to stop eating. The body can also move in the other direction to stimulate feeding when a person feels hungry. Question 1 - The body only has one orexigenic hormone that is released from the gut to increase food intake. What is it?
Gherkin
Adipose tissue or body fat is loose connective tissue composed mostly of adipocytes, which is derived from preadipocytes. Its main role is to store energy in the form of lipids. Which of the following is NOT secreted by adipose tissue? A. leptin B. adipsin C. visfatin D. ghrelin
Ghrelin - intestines
Appetite is the desire to eat food, felt as hunger. Appetite serves to regulate adequate energy intake to maintain metabolic needs. It is regulated by a close interplay between the digestive tract, adipose tissue and the brain. Which hormones will increase when you are in fasted state? A. Glucagon B. Insulin C. CCK D. Gastrin
Glucagon
To be considered a glucogenic amino acid, catabolism of the amino acid must yield selected intermediates of the TCA cycle. Conversion of amino acid to glucose is accelerated by high: A.Glucagon:insulin ratios and glucocorticoids B. insulin C. Oxytocin D. Estrogen
Glucagon:insulin ratios and glucocorticoids
Two types of cells namely osteoblast and osteoclast are involved in bone development. Osteoblast cells are responsible for bone building while osteoclast cells are responsible for bone break down. Both osteoblast and osteoclast are influenced by hormones to function properly. A hormone that is antagonistic to osteoblast is Glucocorticoids Androgen Estrogen Progesterone
Glucocorticoids
In addition to a major body waste product, urea is the by-product of protein. Urea contains nitrogen (N), thus the more protein one eats the more nitrogen he or she is able to excrete in the form of urea through urination. Q2: This concept can also be applied to _________? Glucose excretion Calcium excretion Hydrochloric Acid excretion Sodium excretion
Glucose Excretion
Which enzyme is involved in the production of glucose (gluconeogenesis)?
Glucose-6-Phosphate
There are many different disorders that can come into play when we talk about micronutrient and macronutrient digestion and absorption. Celiac sprue is characterized by lesions of the small intestinal mucosa that is caused by gluten sensitivity. People with this disorder are unable to absorb gluten and usually have to have gluten-free diets. Pancreatic deficiency is caused by the presence of a large amount of undigested fat, which results in a lack of pancreatic digestive enzymes. A symptom of this illness is severe abdominal pain and steatorrhea. Necrotizing entereocolitis is an immaturity or disruption of the intestinal mucosal barrier by fatty acids. Newborn infants are generally susceptible to this disease. Q2: Celiac sprue is related to an intolerance of what substance? Glucose Wheat Gluten Starches
Gluten
The body uses carbohydrates as a main source of energy. Glucose is the most important carbohydrate that gets metabolized. Complex carbohydrates must be broken down in the gut to disaccharides or monosaccharides, which, depending on their identity, will feed into the glycolytic pathway at different points. Upon ingesting carbohydrates, the body must respond to the dietary intake accordingly by either using the carbohydrates to provide energy or storing them to be used later. The process of breaking down glucose to release energy is called glycolysis and the process of storing glucose for later use is called glycogenesis. Question 1: When fructose enters the glycolytic pathway in the liver, it bypasses regulation by the rate limiting step glycolytic enzyme _______________. A. Enolase B. Phosphofructokinase-1 C. Glyceraldehyde-3-P dehydrogenase D. Pyruvate Kinase
Glyceraldehyde-3-P dehydrogenase
When fructose enters the glycolytic pathway in the liver, it bypasses regulation by the rate limiting step glycolytic enzyme _________
Glyceraldehyde-3-P dehydrogenase
When fructose enters the glycolytic pathway in the liver, it bypasses regulation by the rate limiting step glycolytic enzyme _______________.
Glyceraldehyde-3-P dehydrogenase
β-oxidation · A process whose primary function is to supply the body with energy and is made up of a series of reactions including oxidation, hydration, another oxidation, and cleavage that continues until all of the CoA substrate has been converted into acetyl CoA o Step one: catalyzed by acyl CoA dehydgroenase § Produces 2-trans-enoyl CoA and FADH2 o Step two: catalyzed by enoyl CoA Hydratase (hydrates trans double bond) § Produces L-3-hydroxyacyl CoA o Step three: dehydrogenase specific of the type of isomer catalyzes a second oxidation step § Produces 3-ketoacyl CoA, NADH, H+ o Step four: 3-ketothiolase catalyzes the thilytic cleavage to acetyl CoA plus an acyl CoA that is 2 carbons shorter. All of the following are products of the β-oxidation process except? o NADH o FADH2 o Acteyl CoA o Glycerol
Glycerol
Iodine is essential for the synthesis of thyroxin, which is secreted by the thyroid gland. Thyroid stimulating hormone (released by the pituitary gland) controls the production of thyroxin through a negative feedback mechanism. In the target cell, thyroxine is converted to T3, which is the active form that controls the rate of metabolism in the body. T3 stimulates mRNA and protein synthesis and is essential for the development of the brain and nervous system. Iodide deficiency results in insufficient production of thyroxine. TSH is constantly released by the pituitary gland causing the thyroid gland to become enlarged, which is relatively painless but can cause pressure on the trachea that can lead to difficulty breathing. This condition is known as a __.
Goiter
___________ is a key protein (that contains zinc) in taste acuity
Gustin
Cholesterol · Serves important roles in the body such as o Precursor of the sex and adrenal steroid hormones o Precursor to bile acids o Component of cell membranes · Inhibited by statins that target the enzyme HMG CoA Reductase, which catalyzes the main regulatory step in the overall pathway. Which form of lipoprotein transports excess cholesterol to the liver for disposal? o LDL o HDL o VLDL o IDL o Chylomicron
HDL
High density lipoproteins are considered to be good cholesterol, as they remove unesterified cholesterol from the bloodstream and return it to the liver. This is seen as reverse cholesterol transport. Unesterified cholesterol can result in plaque formation and atherosclerosis. Very low density lipoproteins, intermediate density lipoproteins, and low density lipoproteins are seen as bad cholesterol. Fatty plaque formation cause by the inflammation of lipids can be reversed by which of the following types of lipoproteins? a. LDL b. HDL c. IDL d. VLDL
HDL
Rate limiting enzyme in biosynthesis of cholesterol
HMG CoA reductase
Which enzyme converts HMG-CoA to mevalonic acid?
HMG-CoA reductase
Which one of the following is not an example of Vitamin C's antioxidant activity? a) Found in the eye to protect against photolytically generated free radicals. b) White blood cells use vitamin C for protection against the reactive oxygen species produced during phagocytosis. c) Hepatocytes in the liver use vitamin to protect against free radicals generated by bile from the gall bladder d) In semen vitamin C protects DNA from oxidative damage.
Hepatocytes in the liver use vitamin to protect against free radicals generated by bile from the gall bladder
Zinc is an essential nutrient for human growth and development. Zinc serves as a critical cofactor for numerous enzymes in the body as well as an integral part of transcription factor proteins that regulate gene expression. Given these functions, individuals experiencing zinc deficiencies express symptoms involving the retardation of normal cell growth and development. An individual experiencing a Zinc deficiency may show all of the following symptoms except: Abnormally Short Stature High Plasma Glucose Levels Poor Wound Healing Delayed Sexual Maturation
High Plasma Glucose Levels
Unlike macronutrient absorption, mineral absorption is not complete. The amount of minerals in the bloodstream is regulated by bone metabolism, diet, and excretion in the urine. Calcium, Iron and Zinc are all found in the diet bound to proteins that must be cleaved in the acidic environment of the stomach before they can be absorbed through specific transporters such as TRPV6 for calcium and DMT 1 for iron in the small intestine. Storage proteins such as metallothienin in cells sequester minerals such as iron and zinc until hormonal feedback control signals that they need to be released in the bloodstream where they are carried by specific proteins. Inhibitors of mineral absorption in the diet include all of the following except: a. Tannins b. Phytic Acid c. Oxalic Acid d. Low pH e. High pH
High pH
A research study linked high levels of physical activity to high vitamin D serum concentration. The probable reason for high vitamin D serum concentration with high physical activity is High physical activity stimulate PTH to increase absorption of vitamin D Vitamin D is fat soluble High physical activity reduces fat and makes more vitamin D available Physical activity increases mobilization of vitamin D
High physical activity reduces fat and makes more vitamin D available
Low insulin, High glucagon, low CCK, increasing ghrelin are all components that indicate _______
Hunger
unger, appetite, and satiety are often terms that are misunderstood within nutrition. Hunger is a physiological state that causes a food seeking behavior. Appetite is a desire or willingness to eat. Satiation is a reduction of hunger and termination of eating. It is marked by a mixture of psychological, physiological, and metabolic events. Whereas satiety, is a physical feeling of fullness that causes an individual to stop eating. Internal factors are mainly responsible for one's drive to eat, or their hunger, whereas external factors are the primary influence for one's psychological drive to eat, or one's appetite. Question 2: The peripheral body systems, the central nervous system, metabolic influences (i.e. blood nutrient levels), and disease states (such as anorexia or obesity) all impact one's _____.
Hunger
The synthesis of collagen depends on a crucial step. Which of the following answer choices names that step? a) Esterification b) Hydroxylation c) The addition of an ether group d) The removal of an amino group from the proline component
Hydroxylation
One of the few examples of excretion of intact proteins from the body is
In the pancreatic fluid from the exocrine pancreas.
The primary route for excretion of small water-soluble compounds from the body is
In the urine filtered by the kidney.
Toxic outcomes from taking in very high levels of supplemental vitamin D include ALL of the following EXCEPT:
Increased colon cancer incidence.
Body Fat Mass regulation is controlled by the mass of adiposity that is already present in the body. Leptin is the hormonal response that is delivered to the brain by adipose cells to induce either an increase or decrease in appetite. Large fat cells synthesize and secrete more leptin to the brain, this in turn decreases appetite, increases thermogenesis, and promotes a negative energy balance with increased activity. As the fat cells decrease in size from the lack of excess food intake, less leptin is secreted and when levels dip below a certain threshold, feeding behavior is implemented to return the adipose cells to their former size at a so called "biological set point" which is highly individualized. When fat cells increase in size and leptin is secreted to the brain, what physiological change would we expect to see? A. Increased appetite B. Increased urine output C. Increased sedentary activity D. Increased thermogenesis
Increased thermogenesis
Epinephrine and norepinephrine's nutrient metabolism effects include all of the following except _______. Stimulates glycogenolysis Stimulates lipolysis Inhibits glycogenolysis Increased metabolic rate
Inhibits glycogenolysis
Zinc, copper, and iron absorption are all related to each other. Transferrin is the iron transport protein that can be inhibited by access amount of copper in the ceruloplasmin. However, high concentration of zinc inhibits the amount of the copper absorption. So therefore, zinc concentration affects the iron absorption to a certain extent. Copper absorption has what sort of impact on the iron absorption? Affects ferritin Changes the conformation of renin to absorb iron Inhibits transferrin Decrease zinc absorption therefore increase iron absorption
Inhibits transferrin
Insulin and glucagon are hormones involved in cellular and organs communication. They are secreted by the pancreas and have the regulation of glucose metabolism as their major function. In fed state, insulin is high and glucagon is low favoring gluconeogenesis; however in fasting state glucagon is high and insulin is low favoring glycolysis. Disorders of these hormones are often found the in human individuals and the most known disorder is the Diabetes, which is subdivided in two types: diabetes type 1 and type 2. Type 1 is the less common. It is possibly an autoimmune disorder in which your immune system destroys the cells in your pancreas that make insulin. Previously referred to as "insulin-dependent diabetes," people with type 1 diabetes must take insulin to stay alive. Type 2 diabetes occurs when your cells don't respond to insulin. Over time, your body reduces the production of insulin and blood sugar levels go up. Which are the most important hormones for glucose metabolism? Which side of the Glycolysis/Gluconeogenesis pathway do they increase?
Insulin (gluconeogenic side) and glucagon (glycolytic side)
The protein effects on homeostatic control involves an increase in insulin (an anabolic hormone), and an increase in glucagon (a catabolic hormone). These hormones come about in a fed state and have an effect on satiety and hunger control. Which two hormones increase due to protein effects on satiety and hunger control? Ghrelin and Insulin Insulin and Glucagon Glucagon and CCK Epinephrine and Ghrelin
Insulin and Glucagon
Anemia is a major global health problem that results from a chronic deficiency of the nutrient
Iron
Iron is the oxygen carrier within the blood. It mostly resides in hemoglobin which transports oxygen from the lungs to surrounding tissues throughout the body. Iron is also used in the electron transport chain as a component of cytochromes. The reduced cytochrome oxidizes iron from the ferrous state to the ferric state. This oxidation allows electrons to move down the chain. The conversion of citrate to isocitrate during the Kreb's cycle also requires an iron-containing enzyme. How is iron involved in energy metabolism?
Iron is a component of cytochromes and its oxidation allows electrons to be transported along the electron transport chain to eventually create energy in the form of Adenosine Triphosphate (ATP).
Meat is an important dietary source of ____________ and _____________ due to the functions of these minerals in muscle tissue.
Iron, zinc
What selenium deficiency disease is characterized by heart deterioration in children?
Keshan Disease
Selenium deficiency disease
Keshan disease
Vitamin D maintains serum calcium and phosphorus levels. When serum calcium is low parathyroid gland secrete the parathyroid hormone (PTH) to stimulate absorption of calcium. The two organs responsible for absorption of calcium in response to PTH are: Liver and lung Liver and Kidney Liver and intestine Kidney and small intestines
Kidney and small intestines
Denatured protein, lipoprotein remnants, and vitamin-albumin complexes can be cleared from the blood through the action of __________________ in the liver.
Kupfer cells
The liver is important for excreting unneeded components of blood. The phagocytes near the vascular spaces in the liver are also known as _______.
Kupfer cells
Which deficiency diseases can result from a lack of adequate protein intake?
Kwashiorkor and Marasmus
Atherosclerosis is a cardiovascular disease where fatty plaques form in arteries. It starts with a tear in the artery wall and then fatty material is deposited in the vessel wall. Eventually the plaque grows to a sized where it narrows the artery and blood flow is limited. It becomes blocked by a blood clot that cannot pass through. Lipoprotein metabolism issues can lead to blocked arteries, specifically, high levels of LDL cholesterol. Which type of cholesterol at high levels can cause Atherosclerosis? A. LDL B. HDL
LDL
__________ converts pyruvate to lactate
Lactate dehydrogenase
Chelation is a reaction between anions that can bind the metal ions. Binded metal ions happen to be unavailable for absorption. As an example phytic acid can bind Fe, Zn, Ca and Mg. Those ions are unavailable for absorption after binding. Another example could be tannins which can bind Fe and decreases absorption. That is the antinutritional effect of both phytic acid and tannin. Microbiome is microorganismal community which, one can say the forgotten organ. Those microorganisms lives mostly within digestive tract especially localized at distal gut in humans. Microorganisms that participate to microbiome are usually symbiotic and ferment fermentable fibers. They can produce SCFA's, serotonin, vitamin. Human microbiome may have a role in immunity, obesity, depression and other mental diseases. Human microbiome can be effected by diet, environment and age. Those factors can effect number and type of microbiome cells which can effect health outcomes. Which one of the following is an undigestible carbohydrate? -Starch -Maltose -Mucilage -Lignin
Lignin
Polyunsaturated fats are essential to our daily lives. They help with growth and daily metabolic bodily functions. These fatty acids can be found in foods and other supplemental forms that our body needs to perform at its highest efficiency. What are the two PUFA? A. Linoleic and linolenic B. calcium and phosphorus C. fat and acid D. muscle and protein.
Linoleic and linolenic
Triacylglycerols, a product of fatty acid synthesis, are insoluble in water and therefore must be packaged into lipoproteins which are secreted into the lymph and ultimately pass into the blood stream. The triacylglycerol is added to chylomicron precursor particles by a microsomal triacylglycerol transfer protein (MTP) which forms a mature triacylglycerol-rich chylomicron. This is then secreted into the lymphatics. The triacylglycerols present in chylomicrons and very low density lipoproteins (VLDL) are then hydrolyzed by lipoprotein lipase (LPL). This enzyme is found in the muscle and adipose tissue and is used in the mechanism for regulating the partitioning of lipoprotein triacylglycerol-derived fatty acids between storage in adipose tissue and oxidation in muscle tissue. Which enzyme releases a triacylglycerol from a chylomicron or VLDL? Microsomal triacylglycerol transfer protein Hormone-sensitive lipase Lipoprotein lipase Protein kinase A
Lipoprotein lipase
The body tends to seek and maintain a condition of balance or equilibrium within the internal environment-known as homeostasis. In order to maintain homeostasis the foods we consume (intake) are broken down/digested using various enzymes that break down our meals to usable parts or nutrients which can then be absorbed by the small intestines. Excess nutrients can be stored in various tissues for future use and/or excreted. The body excretes the waste products of metabolism or other non-usable/excess products. The major sources of nutrient excretion includes: fecal excretion, renal excretion, dermal excretion, and respiratory excretion. Question 1: Which organ extracts nutrients, toxins, and bile pre-cursors from the blood? A. Stomach B. Pancreas C. Small Intestines D. Liver
Liver
The urea cycle occurs where in the body:
Liver cells
Digestion (the process by which food is broken down into forms the body can absorb) takes place in different organs throughout the length of the gastrointestinal tract, with the help of secretions from accessory organs. The stomach is the site of more physical digestion, while chemical digestion occurs more so in the small intestine. Carbohydrate digestion begins in the mouth via salivary alpha-amylase, then they are further digested by pancreatic alpha-amylase and brush border enzymes in the small intestine. Most carbohydrates are broken down into glucose. Lipid digestion also begins in the mouth with lingual lipases, but a major part of the process is emulsification of fats in the stomach, which then pass to the small intestine and are further digested by pancreatic enzymes and bile salts. Micelle formation is critical in digesting some fats, as it makes naturally hydrophobic fats water-soluble. Protein digestion involves denaturing them in the mouth, stomach (by stomach acid and pepsin), then small intestine where its amino acids become free flowing. Bile is produced by the ___, but is stored in the ___, until it travels to the ___, where it emulsifies ___, a macronutrient.
Liver, gall bladder, stomach, lipids
Long chain fatty acids are synthesized in the liver as well as the adipose tissue. To create these fatty acid chains, substrates and intermediates possess esters of fatty acids and CoA. Long chain fatty acids can also be synthesized in lactating mammary tissue where the use of medium chain fatty acids become esterified to glycerol that is used in milk fat. However, there is a difference in substrates in ruminants and non-ruminants. Where are long chain fatty acids synthesized within the human body? A. liver B. Adipose tissue C. Both A and B D. muscle tissue.
Long chain fatty acids are synthesized in both the liver and the adipose tissue.
Blood pH is LEAST likely to be affected or regulated by which of the following factors?
Losing excess moisture through the skin by perspiration
Antioxidants can, among other functions, reduce the oxidation of lipids inside the body. This oxidation can cause tissue damage, so reducing it is important in maintaining overall health. These antioxidants act by preventing the oxidation of another compound by becoming oxidized themselves, donating an electron in a redox reaction. Which of the following is NOT considered an antioxidant that helps prevent oxidative damage in the body? A. Vitamin C B. Magnesium C. Selenium D. Vitamin E
Magnesium
Normal blood clotting is impacted by ALL of the following nutrients EXCEPT
Magnesium
A child in a semi-starvation condition with very little body tissue would most likely be classified as suffering from
Marasmus
Low protein quality and protein intake in children can result in protein deficiencies and malnutrition. Two of the major ones are kwashiorkor and marasmus. Kawashiorkor characterized by edema, irritability, anorexia, ulcerating dermatoses and an enlarged liver with fatty infiltrates. This is usually due to a deficiency in a nutrient such as iron, folic acid, iodine, selenium, or vitamin C, usually those involved with anti-oxidant protection. Marasmus is a form of sever protein malnutrition. Children with marasmus look emaciated and their body weight can reduce up to 80% of the normal weight for their height. This can also lead to extensive muscle and tissue wasting and variable edema. This can progress to the point of no return. Which protein deficiency with associated with a lack of energy and protein together? Kwashiorkor Marasmus
Marasmus
Which enzyme releases a triacylglycerol from a chylomicron or VLDL?
Microsomal triacylglycerol transfer protein
There are different types of muscles in the human body such as skeletal, smooth, and cardiac muscle. Satellite cells are precursors to skeletal muscle cells and are located at the surface of basal lamina of the myofiber. These cells are used when muscle becomes injured or are used too often. Which cells have plasticity and helps repair, revitalize, and mediate skeletal muscle tissue? Skeletal muscle Muscle satellite (stem) cells Myocytes Osteocytes
Muscle satellite (stem) cells
A characteristic feature of red muscle fibers, in contrast to white muscle fibers, is a higher content of the protein, ________________, which allows for greater ___________ activity.
Myoglobin, aerobic
The Pentose Phosphate Pathway is a metabolic pathway parallel to glycolysis that generates _________ (5-carbon sugars). While it does involve oxidation of glucose, its primary role is _______
NADPH andpentoses; anabolic
Recent studies show that most people around the world have sodium intake averaging 156 mmol/da, which is significantly greater than the UL and DV on U.S. food labels of 100 mmol/da. A physiological factor that has been hypothesized to explain this results is:
Na intake significantly less than 156 mmol/day increases plasma renin activity to conserve sodium in the body.
In oxidative reduction reactions, NAD and NADP accept and donate electrons. NAD is a coenzyme for the degradation of amino acids, carbohydrates, lipids and alcohol in order to produce energy. NADP is a coenzyme in the synthesis of macromolecules. Which water-soluble vitamin is utilized as a coenzyme in the form of NAD and NADP?
Niacin
Niacin plays a role in converting carbohydrates into glucose, metabolizing fats and proteins, and keeping the nervous system working properly. Niacin also helps the body make sex- and stress-related hormones and improves circulation and cholesterol levels. When an individual cannot absorb niacin or the amino acid trytophan it may cause symptoms that involve the skin, digestive system, and the nervous system. Niacin deficiency can cause many different diseases, Pellagra being a main one. The four D's of Pellagra include dermatitis, diarrhea, dementia, and if the niacin deficiency is not treated it can be fatal. Patients who are diagnosed with Hartnup's disease, are experiencing what kind of deficiency? 1. Thiamin 2. Niacin 3. Vitamin B3 4. A&C 5. B&C
Niacin
Which water-soluble vitamin is utilized as a coenzyme in the form of NAD and NADP?
Niacin (B3)
Bone remodeling: In order for new bone to be rebuilt old bone must be broken down. This occurs in a cycle where osteoblasts are responsible for the rebuilding action and osteoclasts are responsible for the bone "breaking" or destroying. The two processes must go hand in hand in order for our bones to respond to their physical requirements and demands. In the presence of Vitamin D ___________ are activated and secrete collagen, osteocalcin to create a form of bone scaffolding. Osteoblasts Osteoclasts BOTH Osteoblasts then Osteoclasts
Osteoblasts
Bone contains two types of cells: osteoblasts and osteoclasts. Osteoblasts help build the bone by secreting a collagen protein matrix. This matrix provides support for the bone. Osteoclasts breakdown bone in areas where the bone is not needed. This is controlled by the PTH, or parathyroid hormone. It is also important to note the existence of osteocytes. Osteocytes secrete bone mineral which causes mineralization. Q1. The final step of repairing a broken bone is the removal of excess bony tissue in order to restore the bone to its original form. What type of cell would be use to complete this step?
Osteoclast
Our bones can be considered a major site for nutrient deposits. One of the major minerals that is collected by our bones and used to strengthen them is calcium. 99% of the calcium in our body is found as either a component of our bones or teeth. Present in the form of hydroxyapatites, calcium compounds are removed from the blood by osteoblasts (bone-forming compounds) and used to form strong bone matrices during bone ossification. A deficiency in calcium, which many women are affected by, can result in the failure to maintain adequate bone mass, also known as ______________ . A. Ossification B. Osteoporosis C. Cellular differentiation D. Crohn's Disease
Osteoporosis
When there is a much greater rate of lipid metabolism relative to carbohydrate metabolism, the body must turn to use of ketone bodies to gain energy. The TCA cycle is not usable, so the acetyl CoA that is available from fatty acids will be condensed together to acetoacetyl CoA. A third acetyl CoA group will condense to acetoacetyl CoA to form 3-hyrdoxy-3-methylglutaryl CoA. It is then cleaved into acetoacetate and acetyl CoA, which will lead to conversions that create 3-hydroxybutryate molecules as well. The formation of these 3 products by condensing 3 acetyl CoA molecules is called ketogenesis. A decrease in concentration of what molecule will decrease glucose use and increase the rate of ketogenesis? A. Citrate B. Oxaloacetate C. Acetyl CoA D. acetoacetate
Oxaloacetate
Which molecule will increase the rate of ketogenesis?
Oxaloacetate
Beta-oxidation is the process in which fatty acids are broken down in the mitochondria into acetyl-CoA. This process is catalyzed with the enzyme acyl CoA dehydrogenase. During this process, both NADH and FADH2 are made. These can be utilized in the electron transport to create ATP. Additionally, the acetyl-CoA molecules can be used in the TCA cycle. Beta-oxidation is performed to produce energy, and it is basically the opposite of fatty acid synthesis. What is the first step of beta-oxidation? a. Hydration b. Thiolysis c. Condensation d. Oxidation
Oxidation
Scientist have known for a long time that hydroxyproline is formed in the maturation of collagen. The 2019 Nobel prize was awarded to Kaelin, Ratcliffe and Semeza for the discovery that hydroxyproline is formed in a regulatory element of gene expression that helps cells sense the external concentration of ___________ .
Oxygen
Thiamin, or vitamin B-1, functions as a coenzyme in the thiamin pyrophosphate form (TPP). In reactions where thiamin is not used as a coenzyme, the form that exists is called thiamin triphosphate (TTP). Low intakes of thiamin may lead to beriberi, a disease which effects the cardiovascular or nervous systems, depending on the type (wet or dry, respectively). Severe deficiencies of thiamin can lead to serious cardiovascular diseases like congestive heart failure and neurologic disorders like dementia. Which of the following are pathways in which thiamin is used? (Check all that apply) A. Gluconeogenesis B. Citric acid cycle C. Calvin cycle D. Pentose phosphate pathway (PPP)
PPP
The activity of the osteoclast is controlled by ________ hormone.
PTH
The activity of the osteoclast is controlled by ________ hormone.
Parathyroid Hormone or PTH
Aside from triacylglycerols, phospholipids are a major form of lipid storage in the body. Phospholipids are similar to triacylglycerol molecules, with the exception of a phospholipid being esterified to the 3rd position of the glycerol molecule instead of a fatty acid group. Phospholipids have a polar head group attached to the phosphate, making one end of it hydrophilic, and the two nonpolar fatty acid groups being a hydrophobic region. This difference across a molecule allows it to work well in forming a lipid bilayer. Different head groups are added to the phosphate of a phospholipid depending on the function that is required. For example, phosphatidylinositol can be cleaved by an enzyme (phospholipase C), which when done in the presence of insulin, can release calcium ions in the cell that will lead to important regulatory gene expression in cell nuclei. What enzyme can attack a phospholipid in a way that immediately produces phosphatidic acid? A. Phospholipase A2 B. Phospholipase B C. Phospholipase C D. Phospholipase D
Phospholipase D
Vegetables that are the main dietary sources of vitamin K include leafy green vegetables, especially collards, spinach, turnip greens, some salad greens, and broccoli. Oils and margarine from plants are considered to be the second best sources of the vitamin. Vitamin K is provided mostly as __________________ from plant foods.
Phylloquinone
Vitamin K: Various vitamins and mineral play key roles in bone homeostasis as well as the processes that involve storage through bone. Vitamin K serves as a cofactor for an enzyme that catalyzes the carboxylation of glutamic acid. There are different forms in plants and animals. This form of Vitamin K is commonly found in plants. Phylloquinone Menaquinone Pectin Tannin
Phylloquinone
What can synthesize linolenic and linoleic acid? a. Plants b. Humans c. Bears d. Cats
Plants
Vit A is a key component in cellular differentiation and acts by interaction with the nuclear receptors referred to as ______________.
RXR or RAR
Iodine deficiency in adults resulting in hypothyroidism is most like to be expressed as
Reduced metabolic rate
How does Phospholipase A2 react with phospholipids?
Releases arachidonic acid from phospholipids
Thyroxine (T4) is a pre-hormone synthesized by the thyroid gland of the human body. T4 is first synthesized as a molecule with 4 iodine residues. T4 is converted to triiodothyronine (T3) by the removal of one iodine residue from the hormone molecule. T3 is the active form of the hormone that serves to regulate the metabolic rates of cells in the body. The conversion from T4 to T3 can happen in the thyroid itself or in the cells of other tissues and organs. The conversion of thyroxine (T4) to triiodothyronine (T3) involves the: Addition of a -OH group Removal of an iodine molecule Conversion of an amide to an amine Cleavage of a carbon-carbon bond
Removal of an iodine molecule
Vitamin A is important in the human body for vision, immunity, growth and differentiation of epithelial, nervous, bone, and other tissue. The three active forms of Vitamin A are retinol, retinal, and retinoic acid. Other forms include Beta-carotene and 11-cis-retinal. Retinal is needed to turn visual light into nerve signals to the brain while Retinoic Acid is needed to maintain proper cell differentiation making up structural components such as cornea and rod cells. The oxidated form of retinol is: A. Retinoic acid B. Retinal C. Retinol D. Beta-carotene
Retinal
_________ is the oxidated form of retinol
Retinal
Biochemical pathways adding a single methyl group to complete the structure of an important compound is LEAST likely to be impaired by a deficiency of the nutrient(s)
Retinol
Vitamin A is required for proper vision and overall eye health. The retinal form of Vitamin A is used in the retina to turn visual light into nerve signal and the retinoic acid form of Vitamin A is used to make up the structural components of the eye such as rods or the cornea. Insufficient Vitamin A will cause xeropthalmia, corneal ulcers, scarring and blindness. In order for Vitamin A to be used as retinal by the eye, β-carotene must first be converted to
Retinol
________ aids the transport of glucose and galactose into the enterocyte
SGLT-1
Growth of muscle fibers resulting from resistance exercise and increased protein synthesis depends on recruitment of ___________________ to donate their nuclei to damaged or stressed muscle fibers.
Satellite stem cells
Hunger is physiological state that causes food seeking behavior. Appetite is the desire or willingness to eat. Satiety is the reduction of hunger and termination of eating and is interplay between psychological, physiological, and metabolic events. Question 2: Between hunger, appetite, and satiety, which is intermittent?
Satiety
In a state of vitamin C deficiency, the disease that is characterized by bleeding gums and lessened ability to heal wounds is
Scurvy
Reactive oxygen species (ROS) are reactive chemicals that contain oxygen such as peroxide and superoxides. They can be created naturally through metabolism, phagocytosis and inflammation. Which of the following is a defense against ROS? a) Vitamin B b) Vitamin K c) Selenium d) Folic Acid
Selenium
3. Neurotransmitters are often times derived from amino acids, which is why they are occasionally called neuropeptides. After consuming a meal, the amount of amino acids available for use or storage increase. This change in amino acid concentration elicits a response on their transporter located in the brain. This ultimately will have an effect on brain function. Which of the following is not an effect epinephrine and norepinephrine has on metabolism? a. Stimulates gluconeogenesis b. Stimulates glycogenolysis c. Stimulates lipolysis d. Increases metabolic rate
Stimulates gluconeogenesis
About 250 grams (1,000 kcal) of our daily intake of food is carbohydrates. These sources can include starch present in grains and certain vegetables (corn, flour, pasta, etc). Carbohydrates include four different categories: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. Monosaccharides include glucose, fructose and galactose. Disaccharides include sucrose, lactose, maltose and trehalose. Oligosaccharides break down components into polysaccharides, which are starches. Different enzymes, specifically the alpha-amylase, can digest all of these different kinds of starches differently. Q1: What substances are included in the category of disaccharides? Galactose, Fructose, Maltose Sucrose, Lactose, Maltose and Trehalose Sucrose, Glucose, Trehalose Maltose, Galactose, Lactose and Trehalose
Sucrose, Lactose, Maltose and Trehalose
The active form of thyroid hormone is (T3/T4) and contains ______ iodine atoms
T3; 3
Zinc deficiency and vitamin A deficiency may have similar clinical symptoms, such as dermatitis, growth retardation. A possible explanation for this interaction is
The alcohol dehydrogenase enzyme needed for retinol metabolism is a zinc-dependent enzyme.
An abnormal concentration of cells or oxygen carrying capacity in the blood has been shown to be possibly related to ALL of the following nutrient interactions EXCEPT
The effect of vitamin D on calcium regulation.
Iodine deficiency, associated with goiter, causes more mental retardation (cretinism) in some populations than in others. One likely explanation for this observation is
The enzymes that activate thyroxin in the brain are different than those that activate thyroxin in the rest of the body.
glycolysis
The oxidation of glucose to pyruvic acid )produces ATP and NADH)
TCA cycle
The oxidation of pyruvate and acetyl-CoA (to CO2 and H2O)
Saliva is where the process digestion begins. It immediately begins to digest nutrients with the help of enzymes and also facilitates swallowing so that food can make it down the esophagus. Starch is what begins to be broken down in the mouth. Starch is a form of carbohydrate, a macronutrient, and is broken down by salivary amylase, which is what is excreted from the mouth and begins the process of digestion. Q: Where does the process of digestion begin and what enzyme is excreted?
The process of digestion begins in mouth with the secretion of saliva that contains the enzyme amylase that breaks down starch.
Branched-chain amino acids undergo oxidative decarboxylation, which is important in aerobic glucose metabolism. Thiamin pyrophosphate (TPP) is a coenzyme involved in this process. It is also a coenzyme for transkeletolase, which converts fructose to pentose. Which is the active form of thiamin?
Thiamin pyrophosphate (TPP)
_______ is secreted in the thyroid in response to TSH.
Thryoxine
Nutrient absorption is important for regulating homeostasis and for providing energy to the body. Minerals such as calcium, zinc, and iron are all very important nutrients that must be absorbed into the body to maintain a healthy lifestyle. If the body isn't absorbing nutrients properly then it can throw the body out of homeostasis and cause a string of negative effects on the body. Q: What is the main role of intake regulation of minerals?
To maintain energy homeostasis.
"Before nutritional biochemistry was a science ancient Greeks wrote that food was made up of "nutriment medicines and poisons." This is still true today and may have some influence on the development of The Upper Tolerable Intake Limits (UL). Along with deficiency concerns the DRI carefully defines an upper limit of certain nutrients that aren't likely to cause adverse effects on consumer, but if consumed above may cause risk
True
Fatty acid production is the excess energy and protein intakes coupled with adequate carbohydrate intake, the carbon skeleton of amino acids may be used for fatty acid synthesis. Carbon skeletons can be used for fatty acid synthesis T or F.
True
Glucose metabolism has three main steps to it: glycolysis, citric acid cycle, and oxidative phosphorylation. The first stage, glycolysis, consists of ten reactions that converts glucose into pyruvate. Within glycolysis the ten steps are split into different categories: the prepatory phase and the payoff phase. They are split into two because the prepatory phase uses energy in order to prepare the system to make more ATP in the payoff phase. True/False. Two ATP are used in the first phase of glycolysis in order to make more energy in the payoff phase.
True
T/F Pepsinogen is a precursor for the stomach enzyme responsible for the degradation of proteins.
True (chief cells release this)
Pellagra can cause symptoms including scaly sores, vomiting, and dementia. Pellagra maycaused by an inability to absorb niacin or the amino acid _______. A. Tryptophan B. Lysine C. Methionine D.Leucine
Tryptophan
Feces and urine serve as the major routes of nutrient excretion but there are other factors to consider in excretory processes. Fecal excretion rids the body of unabsorbed material (i.e. fiber), endogenous excretions (i.e. recycled purines), and biliary excretions into the feces (i.e. cholesterol). Renal excretion involves a filtration process and recovery of nutrients by the kidneys. The kidneys eliminate excess organic waste and metabolites in the form of urea (i.e. potassium). Protein and micronutrients are continually loss through dermal excretion. The respiratory system serves as an elimination avenue to excrete CO2- a byproduct of various reactions in which O2 is consumed and CO2 is produced and moves through the veins and to the lungs for excretion. Question 1: The __________________ of the kidneys recovers nutrients such as glucose, Ca2+, and amino acids. A. Cortex B. Glomerulus C.Tubule D. Bowman's Capsule
Tubule
What transports cholesterol and FAs from liver?
VLDLs
Vit K is metabolized by becoming part of chylomicrons that are carried to the liver. Once in the liver, Vit K is incorporated into ______ and carried to the extra-hepatic tissues via _______
VLDLs; LDLs
Cholesterol in the skin is converted to what?
Vit D
Muscular atrophy can be caused by a lack of physical activity or by neurogenic atrophy, a condition caused when the nerve that connects to a muscle is damaged. What nutrient has recently been associated with this condition?
Vit D
Ricket's represents a deficiency in which vitamin?
Vit D
Which vitamin binds with Vit K bind to make Vit K more active and regulate blood clotting and bone mineralization?
Vit D
Which vitamin protects fatty acids from oxidative damage?
Vit E
During the formation of bone, osteoblasts are activated by Vit D. For correct bone mineralization, the action of which other vitamin is also required?
Vit K
Which vitamin is made (in small quantities) by bacteria in the large intestine?
Vit K
There are two main hormones that have an impact on nutrient utilization, insulin and glucagon. Other hormones in the body rely on specific nutrients from our diet to be synthesized, such as serotonin. Some hormones are even synthesized within the gut such as catecholamines. Q1: A deficiency in what vitamin can cause blindness due to a deterioration of mucus forming cells?
Vitamin A
Large intestinal bacteria play a crucial role in the digestive process: It serves to prevent pathogenic bacteria from growing; it helps maintain a healthy colon by producing by-products that can be used for energy; and it helps to produce some vitamin K that can be absorbed from the colon. Multiple Choice Which vitamin is made by bacteria in the large intestine Vitamin K Vitamin A Vitamin C Vitamin E
Vitamin K
Osteoporosis is the body's failure to maintain adequate bone mass. In healthy individuals, there is an equal balance of osteoblasts and osteoclasts, which build and breakdown bone respectively. However, individuals with osteoporosis are not able to maintain this balance and their bones become porous and fragile. It has been shown that osteoblasts secrete a protein called osteocalcin, which is vital in metabolic regulation and bone formation. The synthesis of osteocalcin is vitamin dependent. Which vitamin is responsible for synthesizing the production of osteocalcin and fighting bone loss in individuals with osteoporosis? A. Vitamin A B. Vitamin B C. Vitamin K D. Vitamin D E. Vitamin E
Vitamin K
Amount of urine a person needs to produce is determined by protein, sodium, and water intake. Q1: Decreasing the amount of ________ and _________ intake will limit the urine output. Water and nitrogen Sodium and Protein Water and Sodium Nitrogen and Sodium
Water and Sodium
The fat soluble vitamins, as the name already says, are soluble in lipids. The fat soluble vitamins are absorbed in fat globules in the small intestine. These vitamins, especially vitamins A and E, are then stored in the body tissues. Overdose intake by a prolonged time of some fat soluble vitamins can be toxic to the body (hipervitaminosis). Also, deficiency of the fat soluble vitamins exists when an individual fat intake is too low or if its fat absorption is compromised. Can blindness be correlated with a special nutrient deficiency or toxicity? If yes, is it a deficiency or toxicity? What nutrient can be responsible for that?
Yes, vitamin A deficiency.
2. Gustation is a key player in overall nutrition and healthy nutrient intake. Gustin, a salivary metalloprotein, contains which mineral?
Zinc
Bones and teeth constitute the largest body storage of ALL of the following minerals EXCEPT:
Zinc INCLUDES: calcium, fluoride, phosphorous
Zinc deficiency in children causes growth retardation. Of the many roles of zinc in metabolism, the one LEAST likely to explain growth depression is
Zinc is a major constituent of the bone mineral hydroxyapatite.
Which of the following is least likely to stimulate gastric secretions?
a drop in pH of the stomach contents
Fatty acid synthesis occurs in the cytosol. It utilizes Acetyl CoA, which is a carbon intermediate that is generated in the mitochondria. Activated acetyl CoA is bound to the enzyme complex malonyl CoA. Steps involved in this synthesize include activation of acetyl -CoA carboxylation and elongation (malonyl-CoA pathway). Elongation includes condensation, which brings two molecules together by the removal of water and reduction, which converts an aldehyde to an alcohol. Dehydration also removes water and is then followed by another reduction step. During fatty acid synthesis what is the compound that is associated with elongation?
acetyl CoA
Beta-oxidation occurs in a cyclic manner, with repeated release of _______.
acetyl-CoA
Choline is a precursor for
acetylcholine (also phospholipids and betaine)
In glycolysis, pyruvate is converted to acetyl CoA under (aerobic/anaerobic) conditions or lactate under (aerobic/anaerobic) conditions
aerobic; anaerobic
The kidneys are an important part of excretion of some nutrients and also retention of other needed nutrients. What hormone helps the kidneys to retain Na?
aldosterone
Glutathione perioxidase
antioxidant enzymes that break down (harmful) peroxides
The omega-6 pathway produces _______ & ______ .
arachadonic acid; docosapentaenoic acid (DPA)
Muscle is a soft tissue in all animals and humans that promotes movement (contraction and relaxation) and strength. Muscle is composed of energy, protein, fat and minerals such as calcium. Muscle can be gained through diet, exercise and strength training and lost through disease, starvation, or sedentary lifestyle. Muscle _______ or _________ is the loss of muscle mass.
atrophy or sarcopenia
Why is it so difficult to quantify the requirements for nutrients when there is so much knowledge about their metabolism?
because individuals and populations vary in their metabolism and requirements due to genetic and environmental differences
Which peptide hormone, located in the anterior pituitary, has the effect to inhibit the perception of pain? a. prolactin b. growth hormone c. beta-endorphin d. follicle-stimulating hormone
beta-endorphin
Insulin is secreted by the _____ cells in the pancreas and glucagon is secreted by the ______ cells in the pancreas.
beta; alpha
Cholic acid and chenodeoxycholic acid are examples of ______ acids
bile
Glycogenolysis
breakdown of glycogen to glucose
An individual with Persistent Adult Lactasia produces an enzyme in the _____ that individuals who do not have this condition are missing.
brush border of the enterocytes
Bitot's spots
buildup of keratin located superficially in the conjunctiva of human's eyes. They can be oval, triangular or irregular in shape. The spots are a sign of vitamin A deficiency and associated with drying of the cornea.
The insulin releasing peptide GLP-1 plays a critical role in weight loss and a method by which we can stimulate release of even higher levels of GLP-1 can be a great benefit to our societal obesity epidemic. The ileal brake is turned on to a higher degree when GLP-1 levels are increased, this slows down mass peristalsis which increases the time the food sits in the intestine. The longer the food remains in the intestine, the greater percentage of the nutrients can be absorbed from it and the longer a feeling of satiety is maintained by the individual, meaning less food consumption. Insulin release is promoted by GLP-1 and consequently glucagon release is inhibited. Pancreatic Beta-cell growth is stimulated and blood glucose levels are kept more constant and under control. All these factors combined make GLP-1 play a vital role in weight loss. What action is GLP-1 most likely to complete when released by the pancreas? A. An increase in Red Blood Cell count B. Promote intramuscular protein synthesis C. Induce the ileal brake and keep blood glucose under control D. Cause drowsiness and a slower reflex response
c. Induce the ileal brake and keep blood glucose under control
Contraction of both skeletal and smooth muscle occurs in response to which nutrient?
calcium
The renal system involves filtration of blood through the Bowman's capsule and subsequent concentration of the fluid in the renal tubule. Concentration the solutes in the urine conserves water, but excess concentration can result in precipitation of solid ________, which can damage the organ or tissues.
calcium oxalate
To prevent muscle atrophy during weight loss, it is recommended to have adequate intake of ______.
carbohydrates
A __________ group must be added to fatty acids in order to cross the membrane to undergo B-oxidation
carnitine
What protein is particularly important for long chain FAs to be transported into mitochondria?
carnitine
Beta oxidation can be defined as a _______ process
catabolic
The purpose of Beta Oxidation is to supply energy, or ATP. Fatty acids are oxidized to produce acetyl CoA, and ultimately result in the maximum amount of ATP per fatty acid molecule. Beta oxidation is the process of removing two carbons from the fatty acid chain. The process occurs through a cycle of oxidation, hydration, oxidation, and cleavage. Q1: The metabolic process beta oxidation can be defined as a _____ process
catabolic
Free radicals are protons/electrons that move around in the body, crashing into tissues and causing damage. Which of the following antioxidants does NOT work by first trapping and stabilizing a single electron from a free radical?
catalase
Which of the following functions has NOT been attributed to Vit D?
catalyzes calcium binding to blood-clotting proteins (functions of Vit D: - immunity to microbial infection by stimulating synthesis of an antibiotic peptide - cellular differentiation)
In contrast to osteoporosis, the diseases osteomalacia and rickets are likely to be caused by low intake of vitamin D, not calcium, and be characterized by a normal volume of bone that is more poorly mineralized.
caused by low intake of vitamin D, not calcium, and be characterized by a normal volume of bone that is more poorly mineralized.
ascorbic acid (where is it found?)
cell cytosol
Vit E (where is it found?)
cell membrane
What are the most biologically active sphingolipids?
ceramide & sphingosine-1-phosphate
What cells secrete pepsin?
chief cells (stomach)
Protein-related diseases are not that common in the US but can occur through consuming poor quality proteins or little protein. In what populations do we see a majority of these diseases?
children
Enterohepatic recirculation is an important process that occurs during the absorptive stages of digestion and during the excretion process. Which of the following is NOT a component process of enterohepatic recirculation?
cholesterol is extracted from VLDL by lipoprotein lipase (processes of enterohepatic recirculation: - cholesterol is converted to bile acids - liver releases bile acids into the bile duct system - colon reabsorbs secondary bile acids)
___________ cause EFAs to have a bent shape.
cis-double bonds
Biochemical change associated with transformation of rhodopsin to opsin
cis-trans rearrangement of Vit A
Unlike many animals, humans are unable to synthesize Vit C, and it is therefore needed in the diet. It has a main function as an electron donor and works as an antioxidant. It also plays an important role in the synthesis of ________.
collagen
Fiber consists of non-digestible carbohydrates found mostly in plants and can have positive health benefits in humans. Which of the following is NOT defined as a component of fiber?
collagen (components of fiber: - chitin or chitosan - lignin - cellulose)
Sally is a vegetarian nutrition student and is concerned she is not consuming enough complete proteins. How can Sally best use her knowledge in order to make sure she supplies her body with these necessary proteins in a safe and effective manner?
conduct a 3-day diet record and compare her amino acid intake with requirements to determine if she is actually deficient in a limiting amino acid
What is it called when a person is born unable to digest any products that contain the disaccharide lactose?
congenital lactase-phlorizin hydrolase deficiency
Hunger and appetite are _______ while satiety is _______.
constant; intermittent
function of cyclooxygenase (COX)
converts EFAs into prostaglandins & eicosanoids
High concentrations of zinc inhibits _______ absorption
copper
Phytic acid binds all of the following except: zinc calcium copper magnesium
copper
Which pathway during omega-6 fatty acid metabolism yields prostaglandins and thromboxanes from arachidonic acid?
cyclooxygenase
Vitamin D is capable of influencing differentiation in some cancer cells. Which of the following is not a type of cancer affected by adequate Vitamin D levels? a. Breast b. Bone c. Skin d. Brain
d. brain
function of lipoprotein lipase
degrades lipoprotein to release FAs and glycerol
Which part of the digestive system is known for its large cell membrane surface area which aids in absorption via active transport and facilitated diffusion of nutrients into the cells
duodenum
Prostaglandins and thromboxanes are _______.
eicosanoids
The following are ALL symptoms and signs or iron-deficiency anemia EXCEPT:
elevation of the iron-binding protein, ferritin, in the blood
Which is NOT a function of saliva?
emulsification of fats into micelles
Increased dietary fiber can be associated with decreased serum cholesterol levels because
enterohepatic recirculation of bile salts is reduced by the bile salts binding to the fiber
The ______ is the average daily nutrient intake level estimated to meet the requirement of half the healthy individuals in a particular life stage and gender group
estimated average requirement
In the muscle, growth hormone stimulates __________ uptake by inducing the expression of lipoprotein lipase.
fatty acid
What component forms the most hydrophobic/non-polar region of a phospholipid such as lecithin?
fatty acid
Iron is used in the electron transport chain as a component of cytochromes. The reduced cytochrome oxidizes iron from the ______ state to the _______ state
ferrous; ferric
Birth defects, such as fetal malformation and spontaneous abortion, have been linked to too little _________ and too much ________.
folate; Vit A
What is the purpose of recommending daily servings of fruits, grains, vegetables, protein and dairy in the Food Guide Pyramid or Choose My Plate instead of listing the required nutrients?
food groups provide a simple way to get all nutrients in a balanced diet
Water soluble vitamins have an important role in the growth, function, and maintenance of body tissues. Unlike fat-soluble vitamins, these vitamins are not stored in the body and are readily discarded through the kidneys, which is why they need to be replaced daily through dietary sources. The water soluble vitamins include vitamin C and the B vitamins such as: thiamin, riboflavin, niacin, vitamin B6, vitamin B12, folate, pantothenic acid, and biotin. The B vitamins primarily function as coenzymes in energy metabolism pathways. Vitamin C plays a key role in the formation of collagen, the synthesis of some hormones and neurotransmitters, and it also acts as a reducing agent or antioxidant. The primary role of vitamin C is __________ A. bone growth B. mineral absorption C. synthesis of red blood cells D. formation of collagen
formation of collagen
gluconeogenesis
formation of glucose from noncarbohydrate sources
glycogenesis
formation of glycogen from glucose
There are specific enzymes and hormones responsible for specific regulation. For example, Glucose-6-Phosphate is the enzyme involved in the production of glucose. This enzyme is essential in the release of glucose into the circulation when blood glucose levels are low. Glucagon is released by alpha cells and promotes increased blood glucose levels by increasing hepatic glucose production. What enzyme is responsible for making fructose-6-phosphate for gluconeogenesis?
fructose 1,6-bisphosphatase
In glycolysis, each glucose molecule is converted via _________________ and generates 2 ATP and 2 NADH
fructose 1,6-bisphosphate
The term created by committees of the IOM to describe isolated, non-digestible carbohydrates which have beneficial physiological effects on humans and can be added back into other foods is ________.
functional fiber
Which compound is the hormone most responsible for causing feelings of hunger?
ghrelin
In the fasted state, which hormone is secreted by the pancreas to increase the availability of glucose in the bloodstream
glucagon
Insulin release is promoted by GLP-1, and consequently ______ release is inhibited.
glucagon
Which group of steroid hormones are released when blood glucose levels are low to encourage glycogenolysis?
glucocorticoids (cortisol)
Glycogen is a way of storing glucose in the muscle tissue and liver; it is in the form of branched chain polymers. The glucose molecules in the polymers are linked together by alpha (1-4) bonds, with alpha (1-6) branches at every fourth glucose in the chain. Glycogenolysis is the process by which this glycogen is broken down in the liver; this is stimulated by the hormone glucagon. Question 2: Glycogen phosphorylase breaks down glycogen into _______________ and a shortened glycogen polymer.
glucose-1-phosphate
Glycogen phosphorylase breaks down glycogen into _______________ and a shortened glycogen polymer
glucose-1-phosphate
One of the primary functions of selenium is its role in the ____________ system.
glutathione perioxidase
All of the following are products of the β-oxidation process except?
glycerol (products of B-oxidation: - NADH - FADH2 - Acetyl CoA
Glucagon initiates ___________.
glycogen catabolism to raise blood glucose
Our sense of taste is an important part of our nutrition. It impacts what we eat. Our tongues consist of papillae which contain the taste buds. These taste buds have nerve endings which relay signals to our brain. The salivary metalloprotein containing zinc is called _____________.
gustin
What protein helps with taste acuity? a. zinc b. retinol c. beta-carotene d. gustin e. opsin
gustin
What enzyme aids the catabolism of glucose to glucose-6-phosphate?
hexokinase
_______ is the first enzyme in the glycolytic pathway that converts glucose into glucose-6-phosphate
hexokinase
If diet is low in cholesterol, HMG-CoA reductase activity will be (low/high) & endogenous cholesterol synthesis will be (increased/decreased)
high; increased
B-12 & folate work together to control __________ levels
homocysteine
Iodide, present in food as Iodine, is used in the synthesis of thyroxine, which is necessary for growth and development. The RDA for Iodide is based on _________.
how much iodide is needed for a steady state in the thyroid gland
Low insulin, High glucagon, low CCK, increasing ghrelin are all components that indicate _______.
hunger
Cholesterol is provided mainly from animal foods. It then diffuses into the bloodstream and can exist protein bound or unbound in the cytosol. it can then be incorporated into membranes or be converted into steroid hormones by mitochondria. Lipoprotein lipase facilitates the uptake from the blood by
hydrolyzing plasma tricylglycerols in circulating lipoproteins
Lipoprotein lipase facilitates the uptake from the blood by ______
hydrolyzing plasma tricylglycerols in circulating lipoproteins
Functional group on a Vit E molecule that stably holds free radical electron
hydroxyl on the chromanol ring
The synthesis of collagen depends on _________.
hydroxylation
The primary integration center in the brain for the hormonal systems and neural systems that regulate food intake and the digestive tract is the _______.
hypothalamus
_______________ amino acids are necessary for development but cannot be synthesized in the body
indispensable
Which of the following statements shows the weakest evidence that a substance is an essential nutrient?
infants hospitalized with intestinal bacterial infections were given infant formula with or without the human milk protein lactoferrin added. The lactoferrin groups recovered faster, indicating that this nutrient was essential
Why are ketone bodies formed when b-oxidation is the exclusive pathway being used for energy production?
insufficient oxaloacetate to combine with the quantity of acetyl-CoA produced
Hormonal factors that tend to elevate blood glucose include all of the following EXCEPT:
insulin (elevate BG: - glucocorticoids - glucagon - epinephrine)
Which hormones affect rate of glycolysis?
insulin, glucocorticoids, glucagon
Cretinism results from an untreated congenital nutrient deficiency. The symptoms of this deficiency are deaf mutism, spasticity, inadequate myelination of nerve cells, and mental retardation. The nutrient involved in this deficiency is _________.
iodine
Fenton reaction (describe)
iron catalyzes conversion of hydrogen peroxide to a hydroxyl radical or peroxide radical
Osteoblasts are the cells responsible for bone formation. Vit K ______.
is a cofactor for modification of bone proteins by osteoblasts
Alpha-linolenic acid is an important dietary constituent because _________.
it is an essential Omega-3 fatty acid
What kind of AAs are degraded into 2-carbon units (like acetyl-CoA)?
ketogenic AAs
Calcium regulation is monitored and regulated by the parathyroid hormone, calcitriol, and calcitonin. When there is low calcium in the blood, the parathyroid gland receives the signals and the parathyroid gland releases the parathyroid hormone into the blood. The parathyroid hormone binds to its receptor on the target cell surface. This then causes reabsorption of calcium. Parathyroid hormone can also cause kidneys to synthesize calcitriol which initiates the reabsorption of calcium from the kidneys to the blood. Which gland synthesizes calcitriol in order to cause reabsorption of calcium? Pancreas b. kidneys c. liver d. parathyroid
kidneys
Two forms of protein deficiency can be seen, especially in children. Kwashiokor is considered a protein deficiency but not an energy deficiency. Marasmus is an energy deficiency including protein deficiency. Kwashiokor usually characterized by edema, anorexia, and an enlarged liver with fatty infiltrates. Kwashiorkor can also be due to a deficiency in iron, folic acid, iodine, selenium, and vitamin C. Infections and oxidative stress can also play roles in causing kwashiorkor. Marasmus is characterized by severe weight loss and subnormal body temperature, decreased pulse and metabolic rate, and constipation. Which protein deficiency is characterized by low amounts of protein but sufficient in calories?
kwashiorkor
Tryptophan is metabolized by the _____________ pathway
kynurenine
Each of the following food components reduce the uptake of minerals from the diet EXCEPT:
lactose
Protein quality is determined by its digestibility and the digestibility of that protein is determined by the amounts of amino acids that are absorbed following the ingestion of a given protein. Animal proteins are of higher quality because 90-99% of the amino acids are absorbed whereas only 70-90% of the amino acids in plant proteins are absorbed. If a diet contains only low quality proteins will it ________? make the necessary proteins from other amino acids to compensate. lead to inadequate availability of selected amino acids and inhibits the synthesis of its own proteins. Some amino acids will be missing but the body doesn't necessarily need them so you will be just fine.
lead to inadequate availability of selected amino acids and inhibits the synthesis of its own proteins.
The main dietary source of vitamin K
leafy green vegetables
Which hormone produced in the adipose tissue that signals the brain (hypothalamus & brain stem) to reduce food intake?
leptin
Which amino acid can be broken down to yield HMG CoA, a key metabolite in cholesterol synthesis?
leucine
(Linoleic/linolenic) acid is pro-inflammatory while (linoleic/linolenic) acid is anti-inflammatory
linoleic (omega-6); linolenic (omega-3)
Insulin controls the uptake of FAs by stimulating ________
lipoprotein lipase
Where does the urea cycle occur?
liver
Where are long chain fatty acids synthesized?
liver & adipose tissue
Bile is produced by the ______ and stored in the _____, until it travels to the _______ where it emulsifies ______.
liver; gallbladder; stomach; lipids
What population group is least at risk for developing osteoporosis?
male athletes
Salivary amylase and pancreatic amylase breaks the alpha (1 --> 4) glycosidic bonds of starch producing all of the following substances EXCEPT
malt liquor (produces: limit dextrin, maltose, maltotriose)
The ileal brake is turned on to a higher degree when GLP-1 levels are increased, this slows down ________ which increases the time the food sits in the intestine. The longer the food remains in the intestine, the _______ percentage of the nutrients can be absorbed from it and the longer a feeling of satiety is maintained by the individual, meaning less food consumption
mass peristalsis; greater
A condition caused by insufficient folate or Vit B12 intake that results in blocked cell division and the development or large nucleated erythroblasts is called _______
megaloblastic anemia
Tryptophan is the precursor to _______ & _________
melatonin; serotonin
Phenylketonuria (PKU): is a clinical syndrome that if goes untreated causes mental retardation with cognitive and behavioral abnormalities caused by elevated serum phenylalanine. What can happen to one if they do not treat Phenylketonuria? a. mental retardation b. loss of hearing c. loss of sight d. all of the above
mental retardation
In muscle, ______ & ______ are contractile proteins
myosin; actin
Tryptophan in converted into 5-hydroxytryptophan (5-HTP) which is subsequently converted into the neurotransmitter serotonin. It has been proposed that consumption of tryptophan or 5-HTP may therefore improve depression symptoms by increasing the level of serotonin in the brain. 90% of the serotonin found in the human body is found in the enterochromaffin cells in the GI tract. Neurotransmitters are stored in the ______________ as vesicles until stimuli arrive to affect their release. A. axon B. nerve axon terminal C. dendrite D. Node of Ranvier
nerve axon terminal
Which of the following is NOT a coenzyme or dietary form of the vitamin Niacin?
nicotine
A conditionally essential nutrient typically___ essential and ____ but becomes essential when synthesis is ____
not, synthesized, inadequate
EPA and DHA are what type of FAs?
omega-3 fatty acids
arachadonic acid
omega-6 PUFA
Osmotic gradients are important for facilitating the movement of water across cells and epithelial membranes in the body. Through the process of osmosis, water is able to move from areas of low solute concentration to areas of high solute concentration. This helps to stabilize solute concentrations at levels that ensure proper cellular function in that area of the body. Regulation of water movement is so precise that plasma osmolality rarely varies within 2% of a typical value. Through the process of ______, water moves from areas of ___ solute concentration to areas of ____ solute concentration.
osmosis; low; high
Carbohydrates, consumed as starch and sugars, make up about 50% of total calories in the diet and are stored in the body as polysaccharides. Salivary and Pancreatic Amylase digest starch to disaccharides such as maltose sucrose and lactose as well as longer limit dextrins. Enzymes specific for these disaccharides break them into monosaccharides that can be transported from the lumen of the intestine via transporters such as GLUT 2 for hexoses and GLUT 5 for fructose in the villi of the intestinal epithelia. Starches that cannot be digested by these enzymes, such as cellulose are called dietary fiber. Carbohydrates are stored as polysaccharides in the body because it lowers the _ ____________ pressure, which allows more storage of sugar with less ___________ in the liver. a. osmotic; glycogen b. internal; water c. osmotic; water d. internal; glycogen
osmotic, glycogen
Carbohydrates are stored as polysaccharides in the body because it lowers the _______ pressure, which allows more storage of sugar with less ________ in the liver.
osmotic; water
Cells in the bone that use hydrochloric acid and proteases to dissolve bone matrix and mineral
osteoclast
All of the following are promoters of calcium absorption from the GI tract EXCEPT:
oxalic acid (inhibits absorption)
In FA biosynthesis, _______ is the main FA produced
palmitate
Gluconeogenesis is a catabolic process in which new glucose molecules are formed and distributed to various tissues from the liver or kidney. It's utilized to prevent hypoglycemia by converting non-carbohydrate molecules to glucose. 2. In which of these organs would gluconeogenesis not occur? a. Pancreas b. Liver c. Kidney
pancreas
________ is part of coenzyme A (CoA), which is necessary to metabolize alcohol, amino acids, carbs, lipids and proteins
pantothenic acid
In the stomach, there are different cells that secrete gastric juices that aid in digestion. Which cells in the stomach secrete HCl to help with protein denaturation?
parietal cells
There are high and low quality proteins in most diets. A majority of animal products are high/complete and plants products are low/incomplete. To compensate for the incomplete protein in plants, one could eat a combination of plants, such as rice and beans. Given the following choices, the food with the highest protein quality would most likely be what?
peanut butter sandwich on wheat break
There are two categories of fiber: functional fiber and dietary fiber. Dietary fiber is found in plants, where as functional fiber has an affect in humans. Fiber adds bulk to food in the stomach, which will slow gastric emptying and create the feeling of fullness. Fiber also has an affect on the lower GI tract, as it is metabolized by colonic microflora making short chain fatty acids, hydrogen, CO2, and biomass. Another non-absorbable plant material that effects digestion is phytate. Phytate is an antioxidant that can reduce risk for colon cancer and protect against osteoporosis. It binds iron, zinc, calcium and magnesium and so can have some anti-nutritional effects. What is a functional fiber found in plants? chitin polydextrose pectin lignin
pectin
Generation of 5-carbon sugar phosphates is dependent on which pathway?
pentose phosphate pathway
The chief cells in the gastric gland of the stomach release a protein called _________.
pepsinogen
Vit K acts as a cofactor for an enzyme that catalyzes the carboxylation of glutamic acid. The carboxylation results in the conversion of glutamic acid to gamma-carboxyglutamic acid. Which Vit K vitamer would you expect to be responsible for the greatest portion of this activity for a vegetarian?
phylloquinone
________ is the form of Vitamin K is commonly found in plants
phylloquinone
Foods rich in whole grains, nuts and legumes may contain what class of compounds, similar in structure or function to cholesterol?
phytosterols
What kinds of lipids are susceptible to lipid peroxidation?
polyunsaturated fatty acids (PUFAs)
Which of the following relationships were NOT used in the 2010 formulation of RDAs for vit D?
populations living at higher latitudes with less intense sunlight have higher rates of diabetes and certain cancers
The amount of urine produced daily in the human body is equal to 1-2 liters per day, but varies based on protein, sodium and water intake. The volume of water consumed in a day is (greater than/less than/equal to) the volume of urine lost
possibly greater than
hexose monophosphate shunt
production of 5-carbon monosaccharides and NADPH
Marasmus results from a deficiency in what?
protein
Protein balance is protein synthesis minus protein degradation. A healthy adult should be in ________, while a healthy child is should be in _______
protein balance; positive protein balance (positive protein balance - synthesizing more protein than the amount of protein degraded)
The B vitamin most involved in decarboxylation reactions
pyridoxal phosphate
Glucose is the primary metabolic fuel. It is derived from dietary carbohydrates, body glycogen stores, or endogenous biosynthesis from non-hexose precursors. Glucose is oxidized, degraded, or metabolized in most of the body such as liver, skeletal muscle, heart, adipose tissue, brain, and blood. There are the catabolic pathways and anabolic pathways involved glucose metabolism; catabolism (oxidation) involves breaking down of complex molecules into simple molecules, while anabolism (reduction) involves synthesis of complex molecules from simple molecules. Glycolysis is the anaerobic breakdown of glucose to ___________
pyruvate
Glycolysis is the anabolic breakdown of glucose to _________
pyruvate
Glycolysis is the breakdown of glucose to yield two pyruvates. This pyruvate is then converted to acetyl CoA under aerobic conditions or lactate under anaerobic conditions. After the conversion to acetyl CoA, the acetyl CoA is entered in to the citric acid cycle, where it is oxidized to water and carbon dioxide. The end result of glycolysis is two pyruvates, two net ATP's (4 ATP's are generated, but 2 are consumed), and 2 NADH's. What enzyme is used to convert pyruvate to acetyl CoA? a. Pyruvate carboxylase b. Pyruvate dehydrogenase c. Pyruvate transferase d. Pyruvate hexokinase
pyruvate dehydrogenase
function of phospholipase C
releases phosphoinositol (PIP) from phospholipids
The conversion of thyroxine (T4) to triiodothyronine (T3) involves:
removal of an iodine molecule
Which form of Vitamin A is essential in the retina of the eye in order to turn visual light into nerve signals to the brain?
retinal
Which form of Vitamin A is essential in the retina of the eye in order to turn visual light into nerve signals to the brain? a. retinol b. retinoic acid c. beta-carotene d. retinal
retinal and retinol
The _____________ form of vitamin A is needed for the differentiation of cells responsible for the make up of cones and rods
retinoic acid
Vitamin A is an essential component of our vision system. The two photoreceptors in the eye are rods and cones. Rods are responsible for vision in dim light. Cones are responsible for vision in bright light. There are three main forms of vitamin A: retinol, retinal, and retinoic acid. These forms of vitamin A had different functions. The __________________ form of vitamin A is needed for the differentiation of cells responsible for the make up of cones and rods. A. retinol B. retinal C. retinoic acid
retinoic acid
Cell differentiation is to _____ as _____ is to 11-cisretinal a. retinol, transforms visual light to nerve signals b. retinoic acid, binds to opsin c. retinal, binds to opsin d. retinoic acid, transform visual light to nerve signals e. retinal, transform visual light to nerve signals
retinoic acid, binds to opsin
In order for Vitamin A to be used as retinal by the eye, β-carotene must first be converted to ___________
retinol
Myofilaments are organized together into repeating units called ___________ that constitute the basic unit of muscle contraction
sarcomeres
Which cells have plasticity and help repair, revitalize, and mediate skeletal muscle tissue?
satellite cells
__________ is described as a reduction of hunger that should cause termination of eating at the end of a meal.
satiety
Tryptophan in converted into 5-hydroxytryptophan (5-HTP) which is subsequently converted into the neurotransmitter _________
serotonin
The major functions of the renal tubule include ALL of the following EXCEPT:
synthesis of glucose (major functions of renal tubule: - secretion of water - absorption of water - absorption of Na)
Low blood calcium causes release of PTH from the parathyroid gland. If Vit D were deficient in that case, which of the following would be LEAST likely to occur?
the PTH will activate calbindin D synthesis in the duodenum to increase calcium absorption
Menaquinone is:
the chemical form of vitamin K that is synthesized in bacteria
Why is there no digestion of starch in the stomach?
the low pH in the stomach denatures amylase
Which is the active form of thiamin?
thiamin pyrophosphate (TPP)
Protein quality is the extent to which a protein meets the body's requirements. This depends upon the protein's amino acid composition. There are twenty amino acids; nine of them cannot be synthesized by the human body on its own. These nine are called "essential" amino acids, indicating that they must come from the diet. Proteins are classified as complete or incomplete based off of quality. Complete proteins contain adequate amounts of all nine essential amino acids, while incomplete proteins lack adequate amounts of one or more essential amino acid(s). Which of the following amino acids is considered to be "essential"? tyrosine glycine threonine cysteine
threonine
There are NINE essential amino acids. Which of the following is considered to be essential?
threonine
All of the following are functions of Vitamin C except: Antioxidant activity Immune function Thyroid hormone metabolism Iron absorption
thyroid hormone metabolism. This is a function of Selenium, not Vitamin C.
What is the function of pyruvate dehydrogenase?
to convert pyruvate to acetyl CoA
All of the following are pharmacological uses of Vitamin E except: Decrease the progression of Alzheimer's Treat those with hypertension Reduce the risk of prostate cancer Reduce Asthma symptoms
treat those with hypertension. The other three answers are known pharmacological uses of Vitamin E.
(T/F) AAs are commonly used by nerve terminals as neurotransmitters.
true
(T/F) An increase in bile acid production would increase cholesterol absorption.
true
(T/F) Medium & short chain FAs enter the mitochondria on their own.
true
(T/F) Over 90% of energy released from food occurs as a result of TCA cycle oxidation
true
(T/F) Selenium plays a key role in thyroid hormone metabolism .
true
What amino acid cannot be produced in adequate amounts by individuals with phenylketonuria (PKU), who are deficient in phenylalanine hydoxylase activity?
tyrosine
Upon traveling to the liver, insulin binds with its receptor ________.
tyrosine kinase
HDL removes ____________ by excreting it into the bile
unesterified cholesterol
Lipid peroxidation is a non-enzymatic process initiated by a free radical that attacks the methylene carbon present between double bonds. The radical eventually creates a lipid peroxide that can damage the structural integrity of lipid membranes. Since double bonds are present in many lipids in our cells and we are encouraged to eat food high in omega 3 and omega 6 fatty acids (both which contain double bonds), unsaturated lipids are highly present in our cells and diet. However, antioxidants like vitamin E and catalase can quench the radical on the lipid and stop peroxidation. What kinds of lipids are susceptible to lipid peroxidation?
unsaturated FA
Best sources of Vit E in the diet
unsaturated fats & oils
Renal excretion involves a filtration process and recovery of nutrients by the kidneys. The kidneys eliminate excess organic waste and metabolites in the form of ______
urea
Thromboxanes (mechanism of action?)
vasoconstriction & platelet aggregation
The kidney plays an important role in water conservation. More water is extracted from the collecting ducts of the kidney and returned to the circulation when __________ stimulates the insertion of aquaporins into the cell membrane
vasopressin (ADH)
An example of a nutrient in which the EAR is defined by its function, which is maintaining hematological status is _______.
vitamin B12
An example of a nutrient for which the EAR is determined by its concentration (i.e. the intake needed to saturate white blood cells) is _______.
vitamin C
We consume many foods that contain antioxidants. Our bodies also contain these antioxidants. Two major examples of this are vitamin C and vitamin E. Vitamin C is a water soluble antioxidant and vitamin E is fat soluble. Vitamin C is also known as ascorbic acid. Most animals are capable of synthesizing their own vitamin C from glucose, although humans cannot. We have to get vitamin C through the food we eat. Vitamin E's most active form is alpha-tocopherol. This is found in nature and in supplements. It also has to be ingested through our diet. Vitamin C is involved in collagen synthesis, iron absorption, immune function, and cancer prevention. Vitamin E is considered a peroxy radical scavenger because it protects fatty acids from oxidative damage. Because it is fat soluble it works in the prevention of cataracts, strokes, and diabetes. Both of these antioxidant vitamins work together in different ways to keep the body healthy. Which vitamin is water soluble and is involved in collagen synthesis, iron absorption, and immune function: a. Vitamin A b. Vitamin D c. Vitamin C d. Vitamin E
vitamin C
Which vitamin is fat soluble and aids in cataract, stroke, and diabetes prevention: a. Vitamin E b. Vitamin D c. Vitamin A d. Vitamin C
vitamin E
If you were analyzing the quality of the diet for a group of children who you suspect of having a nutritional cause for being abnormally short in stature relative to their age, you would be LEAST concerned about the quantity of ____________ in the diets.
vitamin K
What side effects would you LEAST expect someone who experiences adult hypolactasia to display after consuming a glass of milk?
vomiting
Where are TGs (for energy) stored?
white adipose tissue
Daniel Rudman, who postulated the idea of conditional essentiality, listed what requirements for the nutrient in the event that a nutrient was withheld from the diet?
- Decline in plasma level of the nutrient into the subnormal range - Appearance of chemical, structural, or functional abnormalities - Correction of both these by a dietary supplement of the nutrient
Phytic acid binds which ions, decreasing absorption?
- Fe - Zn - Ca - Mg (NOT copper)