Carbohydrates Flashcards
wha are the elements present in compond that are considered carbohydrates
Carbon, hydrogen and oxygen
Fuctional groups typically found in carbohydrates
Carbonyl and hdroxyl group
what does caboxyl grp contains
Carbon and oxygen connected by double bond
Hydroxyl grp contains
Oxygen that is covalently bonded to hydrogen atom
Compounds that can donate electrons during chemical reaction
Reducing substances
are all carbohydrates a reducing substaces?
No ; only some such as glucose and fructose which have free carbonyl grps
Reducing sbstance should contain?
Active aldehyde and ketone group
Enumerate the reducing substance
- glucose
- galactose
- lactose
- maltose
- fructose
Enumerae the non reducin substance
- sucrose or table sugar
Primary source of energy for humans
- glucose
molecules / macromolecules that provide energy to the body
- carbohydrates
- amino acids
- glycerol
- lipids
- ketones
carbohydrates provide energy to?
-erythrocytes
- brain
- human retinal cells
carbohydrates provide energy to?
-erythrocytes
- brain
- human retinal cells
What are the non carbohydrate sources?
- amino acids
-lipids - ketones
- glycerol
carbs classification
- size of the base of carbon chains
- location of the CO function grp
- number of sugar units
- stereochemistry of the compound
Contains 3 carbons
Trioses
Contains 4 carbons
Tetrose
Contains 5 carbon
Pentoses
Contain 6 carbons
Hexoses
2 types of carbs based on the location of carboyl grp
Aldose and ketose
Location of carbonyl grp in the aldose
Terminal part (at the end of the carbon chain)
Location of the carbonyl grp in the ketose
Middle of the carbon chain
Example of aldose sugar?
Glucose
Example of ketose sugar?
Fructose
Simple sugar tha cannot be hydrolyzed into simpler forms
Monosaccharide
List the monosaccharides
Glucose, fructose, galactose
Joining of 2 carbohydrate molecules
Disaccharides
What links the 2 carbohydrate molecules
Glycosidic linkage
List the disaccharides
maltose, lactose, sucrose
Raffinose cosists of
1 glucose,1 galactose,1 fructose
stachyose consists of
2 galactose,1 glucose,1 fructose
Found in sugar bits (malasses) and whole rains
Oligosaccharide
Lists of polysaccharides
Starch and glycogen
Hydroxyl grp that is located on the right of fisher projection
Dextrorotatory
Hydroxyl grpthat is located on the left side of fisher projection
Leverotatory
Responsiblefor the digestion of the polymers such as starch and glycogen
Salivary and pancreatic amylase
His further hydrolyzed the polymers into monosaccharides
Maltase
sucrase will be further hydrolyzed into
Sucrose to glucose to fructose
Lactase will be further hydroyzed to
Lactose to glucose to galactose
What will happento monosaccharides after being hydrolyzed by maltase
Absorbed by the gut and transported to the liver by the hepatic portal venous blood supply
Monosaccharide such as glucose are transported to the liver through _____
Hepatic potal venous blood supply
3 possible metabolic pathways
- embden meyerhof pathway
- hexose monopphosphate shunt
- glycogenesis
First step of all 3 pathways
Glucose is converted to glucose 6 phosphate using ATP
Enzyme that converts glucoseinto glucose 6 phosphate
Hexokinase
Pathway where glucose is broken down into 2 to 3 carbo molecules of pyruvic acid -> convertd into acetyl coA and enter TCA
Embde meyerhof pathway
What type of pathway is EMF
Aerobic pathway
Substrates tha can enter EMF aside from glucose
Ketones, amino acids, fatty acids, and glycerol
The formation of glucose fronon carbohydrate sources
Gluconeogenesis
What is gluconeogenesis
The formation of glucose fro non carbohdrate sources such as glycerol
What is glycolysis
The process of breaking down of glucose into pyruvate to produce ATP
two products of hexose monophosphate shunt
ribose 5- phosphate and NADPH
first step of hexose monophosphate shunt
glucose 6 phosphate to 6 phosphogluconic acid
this pathway permits _____ to enter glycolytic pathway
pentoses ; hexose monophosphate shunt
function of NADP
protects the lipid bilayer and the other cell enzymes from destruction
first step of glycogenesis
glucose 6 phosphate is converted to glucose 1 phosphate
what happens after glucose 1 phosphate is formed?
converted to uridine diphosphoglucose
which enzyme is responsible for converting UDP- glucose to glycogen
glycogen synthase
glycogen primarily stored where?
muscle cells and liver
metabolism of glucose molecule to pyruvate or lactate for production of energy
glycolysis
formation of glucose 6 phosphate from noncarbohydrate sources
gluconeogenesis
breakdown of glycogen to glucose for use of energy
glycogenolysis
conversion of glucose to glycogen for storage
glycogenesis
conversion of carbs to fatty acids
lipogenesis
decomposition of fat
lipolysis
what happens to plasma glucose concentration during glycolysis
decreases
effect of gluconeogenesis on plasma glucose concentration
increases
how does glycogenolysis affect glucose concentration
elevates glucose
effect of glycogenesis on plasma glucose concentration
decreases
how does lipogenesis impact glucose concentration
decreases
what happens to glucose concentration during lipolysis
increases
hormones that control blood glucose
insulin and glucagon
insulin is synthesized by?
beta cells of the islet of Langerhans
when is insulin normally released
blood glucose is high
primary role of insulin
responsible for the entry of glucose into the cells
how does insulin regulate glucose levels
increasing:
-glycogenesis
-lipogenesis
-glycolysis
inhibit:
-glycogenolysis
insulin is called?
hypoglycemic agent
why is insulin called hypoglycemic agent
it decreases blood sugar levels by inhibiting glycogenolysis
why is insulin called hypoglycemic agent
it decreases blood sugar levels by inhibiting glycogenolysis
glucagon is synthesized where?
alpha cells of the islets of Langerhans
when is glucagon released
during stress and fasting state
how does glucagon regulate glucose level?
increasing:
- glycogenolysis
- gluconeogenesis
glucagon is also called
hyperglycemic agent
why is it called hyperglycemic agent
increases blood glucose levels
what happens when blood glucose levels are high
insulin is released by the beta cells of the islets of Langerhans
- stimulating the cells to take up glucose and promoting storage as glycogen in liver and muscles
primary function of glucagon in the body
stimulate liver cells to convert glycogen into glucose
process in which glucagon stimulate to produce glucose from amino acids
gluconeogenesis
Gluconeogenesis occurs in what organ?
liver
what is epinephrine and where is it released from?
catecholamine ; adrenal medulla
epinephrine effect
-inhibits insulin secretion
- increase glycogenolysis
- increases lipolysis
what hormone is released by the adrenal cortex and its effect on glucose metabolism
glucocorticoids (cortisol) ;
- decreases the glucose uptake by the cells (less glucose is absorbed into the bloodstream)
- increases gluconeogenesis
- lipolysis
function of ACTH (adrenocorticotropic hormone)
- stimulates the adrenal cortex to release cortisol
-glycogenolysis
-gluconeogenesis
hormone released by thyroid gland and its effect
thyroxine (T4);
-glycogenolysis
-gluconeogenesis
-intestinal absorption of goucose
function of somatostatin and where is it released from?
inhibits:
-insulin
-growth hormone
-glucagon
-endocrine hormones
released from:
-delta cells of the islet of Langerhans
group of metabolic diseased characterized by hyperglycemia resulting from defects in insulin secretion or action
diabetes mellitus
old classification of type 1 IDDM and type 2 NIDDM is classified according by?
National diabetes group
IDDM MEANING
insulin dependent diabetes mellitus
NIDDM meaning
non insulin dependent diabetes mellitus
old classification of type 1 and type 2 is classified according by?
International expert committee
new categories of diabetes is by?
-american diabetes association
-world health organization
type 1 IDDM is also known as
- insulin dependeng
- juvenile on set
- brittle
- ketosis prone diabetes
type 1 DM is usually diagnosed to?
-children
-teen
-young adults
unpredictable swings of blood glucose levels
brittle diabetes
unpredictable swings of blood glucose levels
brittle diabetes
production of ketone bodies coming from fat bodies
ketosis prone diabetes
causes of type 1 DM?
results from the cellular-mediated autoimmune destruction of the beta cells of the islet of Langerhans - leading to absolute insulin deficiency
antibodies that destroy the beta cells of the pancreas in type 1
- islet cells autoantibodies
-insulin autoantibodies
-glutamic acid decarboxylase autoantibodies - tyrosine phosphatase IA2 and IA-2B autoantibodies
Type 1 dm constitutes
10 to 20% of all cases of DM
risk factors for developing type 1 dm?
-genetic
-autoimmune
-environmental
characteristics of type 1 DM?
abrupt onset, insulin dependence, ketosis tendency
signs and symptoms of type 1 dm
-polydipsia
-polyphagia
-polyuria
-rapid weight loss
-hyperventilation
-mental confusion
-loss of consciousness
microvascular complications associated with type 1
nephropathy
retinopathy
neuropathy
type of administration is required for type 1 dm
Parenteral administration of insulin
no known etiology, strongly inherited, lacking beta cell autoimmune, requiring insulin replacement
idiopathic type 1 diabetes
type 2 dm is also known as
-non insulin dependent
-maturity onset/ adult
-ketosis resistant
-receptor deficient
-stable diabetes
causes of type 2 dm
insulin resistance and insulin secretory defects
characteristics of type 2 dm
-adult onset
-milder symptoms
-ketoacidosis
risk factors for type 2
-genetic
-obesity
-race
-sedentary lifestyle
-PCOS
-dyslipidemia
-hypertension
signs and symptoms of pcos
-irreg menstruation
-hirsutism (excessive hair growth)
-oilness skin
-acne
microvascular and microvascular complications associated with type 2
macro:
-coronary heart disease
-cardiovascular dxs
micro:
-nephropathy
-retinopathy
-neuropathy
type of medications used to manage type 2
-oral agents or hypoglycemic agents such as metformin
any degree of glucose intolerance with onset of first recognition during pregnancy
gestational diabetes mellitus
risk for infants born to mothers with gestational diabetes
-respiratory distress syndrome
-hypocalcemia
-hyperbillirubinemia
causes of respiratory distress syndrome in infants
breathing difficulty due to immature lungs - increased glucose delay the development of the lungs
what is hypocalcemia and what causes it in infants?
decreased blood calcium due to low parathyroid hormone
what contributes to hyperbilirubinemia in infants?
prematurity and polycythemia
screening for gestational diabetes performed
between 24 to 48 weeks of gestation
specific types of diabetes associated with secondary conditions?
-genetic defects of beta cells function
-pancreatic dxs
-endocrine dxs
-drug or chemical induced
-insulin receptor abnormalities
- genetic disorders
increased levels of growth hormone
acromegaly
increased production of cortisols
Cushing’s syndrome or hypercortisolism
lab finding of glycosuria?
presence of glucose in urine
laboratory findings in hyperglycemia?
-increased glucose in plasma and urine
-increased urine specific gravity
-ketones in urine and serum
-decreased blood and urine ph
-electrolyte imbalance
electrolytes imbalance due to hyperglycemia
low sodium concentration and high potassium concentration
-sodium due to polyuria
ADA recommendation for diabetes testing in adults (age, year, and using)
- starting the age of 45
- every 3 years
- using: HbA1c, fasting plasma glucose, 2 hour 75 mg oral glucose tolerance test
who should be tested for Diabetes outside of the age of 45 recommendation?
overweight and have additional risk factors
hyperpigmentation of the skin, dark areas in the armpits.or groins
acanthosis nigricans
asymptomatic children be tested for type 2 dm when?
-begin at age 1/onset puberty
-follow up testing every 2 years
asymptomatic children be tested for type 2 dm when?
-begin at age 1/onset puberty
-follow up testing every 2 years
risk factors that when present with being overweight indicate the need for diabetes testing in children
-family history of type 2
-race or ethnicity
-signs of insulin resistance
-GDM
test used to diagnose GDM
2 hour OGTT using 75 g glucose load
fasting requirement for 2 hr OGTT
8-10 hours but not more than 16 hours
at what plasma glucose level do glucagon and other glycemic factors get released
65-70 mg/dL (3.6-3.9 mmol/L)
at what plasma glucose level is associated with observable symptoms of hypoglycemia?
50-55 mg/dl (2.8 to 3.1 mmol/L)
laboratory findings that are associated with hypoglycemia
-decreased plasma glucose levels
-extremely elevated insulin levels in patients with pancreatic beta cell tumors
result from the deficiency of specific enzymes that alter glycogen metabolism
glycogen storage diseases
what is von gierke disease and what enzyme is deficient?
-type 1A glycogen storage dxs ;
-caused by deficiency of glucose 6 phosphatase
von gierke dxs leads to?
serve hypoglycemia
symptoms of liver forms of glycogen storage dxs
hepatomegaly
hypoglycemia
symptoms of galactosemia
-failure to thrive
-diarrhea
-vomiting
primary enzyme deficiency in galactosemia
galactose 1 phosphate uridyltransferase
other enzymes that may be deficient in galactosemia
-galactokinase
-uridine diphosphate galactose 4 epimerase
laboratory test used to confirm the enzyme deficiency in galactosemia
-erythrocyte galactose 1 phosphate uridyltransferase activity test
enzyme deficiency associated with essential fructosuria?
fructokinase deficiency
defect in hereditary fructose intolerance
defect in fructose 1,6 biphosphate aldolase B activity
causes the fructose 1,6 biphosphate deficiency
fructose 1,6 biphosphatase
What is glycolysis
The process of breaking down of glucose into pyruvate to produce ATP
