Nutrition 2000 Exam 3

Emily Bourne- Spring 2023

What are the building blocks of protein?

What are the building blocks of protein?

amino acids

What are the different structures of protein?

-carbon atom with amine group and acid group attached

-disitive chemical side chain attached to the center carbon of the backbone

What are the essential amino acids?

histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine

What are the nonessential amino acids?

alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, proline, serine, tyrosine

What is a conditionally essential amino acid?

nonessential amino acid can become an essential amino acid

What are the conditionally essential amino acids?

tyrosine, cysteine, proline, arginine, glutamine

What are the precursors of essential amino acids?

phenylalanine, methionine, serine, glutamate, glutamine, aspartate, ammonia

What are the different protein structures?

primary, secondary, tertiary, quaternary

What is the protein structure of hemoglobin?

quaternary structure

What happens to the amino acid sequence of sickle-cell anemia?

instead on glutamic in the sequence it is replaced with valine

How is protein digested?

What are the different hormones involved in protein digestion?

secretin and cholecystokinin (CCK)

What are the different enzymes used in protein digestion?

dipeptides, tripeptides, and amino acids

What roles do proteins play in the body?

-regulation of gene expression

-provide structure and movement

-building enzymes

-building hormones

-neurotransmitters

-building antibodies

-transporting substances

-maintaining fluid and electrolyte balance

-maintaining acid-base balance

-provide energy and glucose

What is the process of protein synthesis?

-occurs in the cytoplasm

-transcription (DNA→mRNA)

-translation (mRNA to ribosomes)

What is protein turnover?

process of breakdown, recovery, and synthesis

What is the DRI for protein for healthy adults

no more than 35% of diet

-0.8g/kg

What happens in the body with an oversupply of amino acids?

-body removes and excretes amine groups

-uses the residues in three ways: meet immediate energy needs, make glucose for storage as glycogen, and make fat for energy storage

What are some examples of positive nitrogen balance?

nitrogen-in exceeds nitrogen out

ex. growing child or pregnant women

What are some examples of negative nitrogen balance?

nitrogen-out exceeds nitrogen-in

ex. muscle breakdown due to injury

What is Marasmus?

wasting, emaciation

-chronic insufficiency of energy and protein

What is Kwashiorkor?

-adequate energy with insufficient protein

-edema due to loss of blood protein

What is the difference between Marasmus & Kwashiorkor?

What is the BMI for someone who is underweight?

less than 18.5

What is the BMI for someone who is overweight?

25-29.9

What is the BMI for someone who is obese?

30-39.9

What is the BMI for someone who is extreme obese?

over 40

What are the different risks of being underweight?

first to die during a siege or famine, hospital stays, wasting disease, cancer

What are adipokines?

hormones released by adipose tissue; helps regulate the inflammatory processes and energy metabolism in the tissues

What are the major obesity-related chronic disease risk?

heart disease, stroke, high blood pressure, high cholesterol, type 2 diabetes, sleep apnea, liver and gallbladder disease

What is the difference between visceral & subcutaneous fat?

visceral is stored within the central abdominal cavity

subcutaneous is fat between the skin

What is body mass index(BMI)?

indicator of health risk from obesity or underweight

What are the risks of having too much body fat?

obesity-related illnesses, chronic diseases, risk from extreme obesity equals the risk of death from smoking, inflammation

What factors affect BMR(table 9.3)?

sum total of all involuntary activities necessary to sustain life, excluding digestion

What are the different ways to measure body composition and fat distribution?

skin fold test, dual-energy X-ray absorptiometry, or waist circumference

What is the hunger-stimulating hormone? Where is it secreted?

Ghrelin which is secreted in the stomach

What is the appetite-suppressing hormone produced in the fat cells that conveys information about body fatness to the brain?

leptin; an adipokine hormone

What are each of the energy yielding nutrients effect on satiety?

-protein has the greatest satiating effect during meal

-carbohydrates provide slowly digestible carbohydrate and soluble fiber, also contribute to satiation and satiety

-fat famous for triggering a hormone that contributes to long-term satiety, goes almost unnoticed by the appetite control system

What are the “stop” and “go” signals?

-”go”: mechanisms that stimulate eating

-”stop”: mechanisms that supress eating

What is the function of Ghrelin?

hunger-stimulating hormone

opposes weight loss

What is the function of Leptin?

regulates frequency of meals

an adipokine hormone

What happens during feasting?

-carbs→glucose→liver & muscle glycogen & body fat

-fat→fatty acids→body fat

-protein→amino acids→body fat & nitrogen lost in urine

What happens during fasting?

-liver & muscle glycogen→glucose→energy

-body fat→fatty acids→energy

What happens when the fast continues beyond glycogen depletion?

-body protein→amino acids→glucose, nitrogen, ketone bodies→energy

-body fat→fatty acids→ketone bodies→energy

What is the body’s response to being energy deficit?

-gradual weight loss is preferred

-fasting

-ketosis

What is the body’s response to energy surplus?

-protein breakdown

-fat broken down to glycerol and fatty acids

-carbohydrate broken down to sugars

-alcohol used for fuel or converted to fat for storage

Anorexia nervosa

-intense fear of body fatness or of weight gain or strive to prevent weight gain although underweight

-cessation of menstruation, mood swings, depression, physical exhaustion, and sleep deprivation

-self starvation

bulimia nervosa

-binge eating and purging or vomiting

-false perceptions of body weight or shape

-fluid electrolyte imbalances, infections, adversely affects dental health

Sleeve gastrectomy

80% of the stomach is removed, leaving a tube-like structure; this greatly reduces the stomach’s capacity and its output of ghrelin

Gastric bypass

surgeon constructs a small stomach pouch and creates an outlet directly to the lower small intestine

Gastric banding

surgeon uses a gastric band to reduce the opening from the esophagus to the stomach. the size of the opening can be adjusted by inflating or deflating the band through a port located just under the skin.

What is the leading cause and second leading cause of death in the U.S.?

1. Heart disease

2. Cancer

What is thrombus?

a stationary clot: tissue death caused is called thrombosis

What is embolus?

a clot broken loose

What is embolism?

clot remains stuck in a narrow artery

What is an aneurysm?

an artery is blocked, it may swell and burst

What are the nonmodifiable risk factors for CVD?

-increasing age

-male gender

-family history

What are the modifiable risk factors for CVD?

-High blood LDL cholesterol

-Low blood HDL cholesterol

-High blood triglyceride levels

-High Blood pressure

-diabetes

What are harmful things that can come from diabetes?

-atherosclerosis

-impaired kidney, eye, and nerve function

What is the second leading cause of disability and death in the U.S.?

Cancer

What happens during plaque development?

Particles of LDL cholesterol become trapped in the blood vessel walls, and these become oxidized by abundant free radicals produced during inflammation.

What does the development of atherosclerosis involve?

-plaque development

-blood clot formation

-hypertension

What is metastasis?

tumor overwhelms the healthy tissue in which it developed or exports its cells through the bloodstream to other parts of the body to initiate other tumors

What is metabolic syndrome?

any three or more of the:

-high fasting blood glucose

-hypertension

-Central obesity

-low blood high-density lipoprotein (HDL)

-High blood triglycerides

What effect does atherosclerosis have on blood pressure?

causes hypertension

What is atherosclerosis?

damage to the cells lining the arteries

What are symptoms associated with diabetes?

-intense hunger

-frequent urination

-intense thirst