Chapter 27 Flashcards
major nutrients
Carbs, Lipids, and Proteins
minor nutrients
Vitamins, Minerals and water
what happens to excess glucose?
it is converted to glycogen or fat and stored
what do soluble fibers do?
reduces blood cholesterol levels
what do insoluble fibers do ?
provide roughage
what are triglycerides also known as?
neutral fats
what are triglycerides used for?
mostly energy storage, but also form protective cushion around organs and insulating layer
Glucose is catabolized in three pathways
Glycolysis
Krebs cycle
Electron transport chain and oxidative phosphorylation
what is Carbohydrate Metabolism ?
Breakdown of glucose
how many calories are yielded from each gram of carbs?
4
what is Lipolysis?
Breakdown of triglycerides
how many calories are yielded from each gram of lipids?
9
The hormone regulating almost all processes of the absorptive state
insulin
Major actions of Insulin
- Enhances diffusion of glucose into muscles and adipose cells
- Glucose oxidation
- Glycogen and triglyceride formation
- Active transport of amino acids into tissue cells
- Protein synthesis
what does excess conjugated or unconjugated bilirubin levels in tissues lead to?
jaundice
what does cholesterol provide a structural basis for?
bile salts
steroid hormones
vitamin D
why is it that cholesterol and other lipids cannot be transported in free form in blood?
because they are not water-soluable
what do high levels of HDLs do?
protect against heart attack
what do high levels of LDLs do?
increase the risk of heart attack
what are nutrients?
substances that promote normal growth, maintenance and repair
the two dietary sources of carbohydrates
- Starch (complex carbohydrates)
- Sugars
two types of fibers that carbohydrates form
insoluble fibers
soluble fibers
the most important carbohydrate
glucose
why is glucose the most important carbohydrate?
to is the fuel used by cells to make ATP
what is the recommended intake of carbohydrates?
45-65% of total calorie intake
which cells rely almost entirely upon glucose?
Neurons and RBCs
in which foods can saturated fats be found?
meat, dairy foods, and tropical oils
in which foods can unsaturated fats be found?
in fats in seeds, nuts, olive oil, and most vegetable oils
the 2 essential fatty acids
linoleic and linolenic acid
in which foods can cholesterol be found?
egg yolk, meats, shellfish and milk products
what are the dietary sources for the essential fatty acids?
Found in most vegetable oils
what do bile salts combine with to form Micelles?
the essential fatty acids (name them)
which type of lipid forms Essential parts of myelin sheaths and cell membranes?
Phospholipids
what are prostaglandins used for?
for smooth muscle contractions, blood pressure control & inflammation
what is the recommended intake of lipids?
Lipids should make up 30% or less of total calorie intake per day
Saturated fats > limited to 10%
Cholesterol > no more than 300 mg
which type of carbohydrate fiber reduces blood cholesterol levels?
soluble fiber
which type of carbohydrate fiber provides roughage?
insoluble fibers
what are neutral fats also known as?
triglycerides
which type of lipid is mostly energy storage, but also form protective cushion around organs and insulating layer
triglycerides
term for the Breakdown of triglycerides
Lipolysis
what causes jaundice?
excess conjugated or unconjugated bilirubin levels in tissues
lipoprotein that protects against heart attack
HDLs
lipoprotein that increases the risk of heart attack
LDLs
substances that promote normal growth, maintenance and repair
nutrients
**which foods contain complete proteins?
eggs, milk, fish, and most meats
which amino acids must be present in order for protein synthesis to occur?
all of them (all or none rule)
which foods contain incomplete proteins?
legumes, nuts, and cereals
function of proteins
use as structural materials and play important roles a functional proteins
what can be used as fuel to generate ATP if the body is lacking carbs and fats in the diet?
proteins
what is the daily requirement for protein intake?
.8g per kg body wight or one egg a day
only vitamins that can be synthesized by the body
Vitamin D,B, and K
what do most vitamins function as?
coenzymes
the 2 divisions of vitamins
water-soluble and fat soluble
water soluble vitamins
B and C (not stored in the body)
fat soluble vitamins
A,D, E and K (stored in the body with exception of vit K)
what are minerals?
Inorganic Substances that are required in moderate or trace amounts amounts
minerals required in moderate amounts
(Ca+, phosphorus, K+, Sulfur, Na+, Mg, and Fe in women)
minerals required in trace amounts
iodine and fluorine
the 2 types of metabolic reactions
anabolic
catabolic
what happens during anabolic reactions?
Larger molecules are synthesized from smaller ones
what happens during catabolic reactions?
larger molecules are broken down into smaller ones
the type of metabolic reaction that requires energy
anabolic
type of metabolic reaction that releases energy
catabolic
What is Metabolism?
The biochemical reactions inside cells involving nutrients
What is Cellular Respiration?
This is a series of catabolic reactions that release energy
what is oxidation?
the gain of oxygen or the loss of hydrogen
the 2 mechanisms for ATP production in cells
Substrate-level phosphorylation
Oxidative Phosphorylation
Substrate-level phosphorylation
High energy phosphate groups are directly transferred from phosphorylated substrates to ADP
Oxidative Phosphorylation
A Chemiosmotic process that Couples the movement of substances across a membrane to a chemical reaction
what is the krebs cycle also known as
citric acid cycle
what happens when dietary protein is in excess?
animo acids are oxidized for energy or Converted to fat for storage
the period during and shortly after eating
Absorptive (Fed) State
what processes happen during the Absorptive (Fed) State?
Absorption of nutrients is occurring and anabolism exceeds catabolism
what is the major energy fuel during the Absorptive (Fed) State?
Glucose
what releases insulin?
the beta cells of the endocrine part of the pancreas
what happens during the Postabsorptive (Fasting) State?
During this state the GI tract is empty and energy is supplied by breakdown of reserves
- Catabolism exceeds anabolism
what releases glucagon?
the alpha cells of the endocrine part of the pancreas
functions of glucagon
- Glycogenolysis and gluconeogenesis in liver
- Lipolysis in adipose tissue
- Modulation of glucose effects after a high protein low carb meal
function of epinephrine in the Catabolic-Anabolic Steady State
Promotes fat mobilization and Glycogenolysis
what is epinephrine released in response to?
low plasma glucose
4 types of lipoproteins
HDLs
LDLs
VLDLs
Chylomicrons
lipoprotein with the highest protein content
HDLs
lipoprotein that transports cholesterol to peripheral tissues
LDLs
lipoprotein with highest cholesterol content
LDLs
lipoprotein that contains mostly triglycerides
VLDLs
lipoprotein that transports excess cholesterol from peripheral tissues to the liver
HDLs
lipoprotein that transports lipids from the intestinal tract to the liver
Chylomicrons
percent of essential fat for women
12%
percent of essential fat for men
3%
term for the process of triglyceride synthesis
lipogenesis
hormone that stimulates glycogenesis
insulin
what hormone stimulates glycogenolysis?
epinephrine
what transports dietary lipids?
chylomicrons
when would lipogenesis occur?
when more calories are consumed than required for ATP needs
what do liver cells convert ammonia into?
urea
the pathway of cellular respiration
glycolysis
krebs cycle
ETC
oxidative phosphorylation
underweight BMI
<18.5
Normal BMI
18.5-24.9
overweight BMI
25-29.9
Obesity BMI
> 30
the most abundant dietary lipid
triglycerides
the end product of glycolysis
pyruvic acid
what must happen for amino acids to be oxidized for energy?
the amine group NH2 must be removed
