Chapter 6: Metabolism Flashcards
___ is the way nutrients enter your body.
The Digestive System
The cells in the Digestive System are replaced ____
every few days
The digestive system contains the body’s most ___ ___ cells.
rapidly multiplying
The __ packages nutrients for transport.
liver
The ___ stores nutrients (like vitamins A and D)
liver
The __ makes important proteins, bile, and glucose
liver
The ___ detoxifies and metabolizes drugs, dismantles old RBC, and makes waste products.
liver
The ___ makes digestive juices.
pancreas
The ___ makes insulin and glucagon to regulate blood sugar.
pancreas
The ___ and ____ deliver nutrients and oxygen to cells. AND also removes waste.
heart and blood vessels
The ___ filter blood
Kidneys
The ___ make Vitamin D, and regulate blood pressure.
Kidneys
- building reactions
- requires energy (ATP)
- making glycogen from glucose
- making insulin from amino acids
- making triglycerides from FA and glycerol
Anabolism
- breaking down
- releases energy (in form of ATP)
catabolism
what is this an example of: oxidation of macronutrients. (anabolism or catabolism)
catabolism
What does ATP stand for?
Adenosine Triphosphate
What does the energy from catabolism form?
ATP
What process coverts glucose to pyruvate?
Glycolysis
4 steps of energy production:
- Glycolysis
- Pyruvate to Acetyl CoA
- TCA cycle (Krebs cycle)
- Electron Transport Chain: transfers energy to ATP
Energetic production: What does the electron transport chain do?
Transfers energy to ATP
Production of ATP: Nutrients are eventually converted to ___ and enter the __ cycle.
acetyl CoA
TCA cycle
Production of ATP: Glucose converts to ___, and then to ___ by glycolysis.
Pyruvate
Acetyl CoA
Production of ATP: Fatty acids and amino acids are converted to ____
acetyl CoA
What is the name for the TCA cycle?
Tricarboxylic acid cycle
In the TCA cycle, enzymes break down acetyl CoA to __ and ___ atoms.
carbon dioxide and hydrogen
TCA cycle: ___ is then carried to the electron transport chain.
Hydrogen
The chemical reactions involved in releasing energy, breaking down compounds, and making new compounds.
Metabolism
Metabolic reactions also use or release energy and therefore affect ____.
body weight
Digestive organs:
liver, pancreas, circulatory system, and kidneys
Digestive organs function to:
4
- break down compounds
- make new compounds
- transport nutrients and oxygen through the body
- remove waste generated by metabolic processes
The digestive system functions to:
5
- transport foods through the GI tract
- produce digestive juices and enzymes
- absorbs nutrients
- provide transport proteins to carry lipids and vitamins to other sites in the body
- reabsorbs salts and fluids
Nutrients absorbed into the bloodstream are taken first to the ___.
liver
The __ is one of the body’s most active metabolic factories.
liver
The __ receives nutrients and metabolizes, packages, stores, or ships them out for use by other organs.
liver
The ___ participated in iron recycling and blood cell manufacture.
liver
After a meal, as blood glucose rises, the pancreas secretes ___
insulin
Insulin prompts cells to take up __ and use it as fuel
glucose
Insulin prompts liver cells to store glucose as ___.
glycogen
When blood glucose falls (between meals), the pancreas responds by secreting ___ into the blood.
glucagon
Glucagon raises blood glucose by signaling the liver to dismantle its glycogen stores and release ___ into the blood for use by all the body cells
glucose
Metabolic reactions that affect the heart and blood vessels include:
-the making and transport of lipoproteins
___ are the carriers of cholesterol and other lipids from the liver to the tissues and back again.
lipoproteins
High blood levels of low-density lipoproteins and very-low-density lipoproteins promote ___, which increases the risk of disability or death from heart attacks and strokes.
atherosclerosis
For 24 hours a day, the __ filter waste products from the blood to be excreted in the ruins and reabsorb needed nutrients, thereby maintains the blood’s delicate chemical balances.
kidneys
The kidneys’ cells produce compounds that help to regulate blood pressure and convert a precursor compound to active vitamin __, thereby helping to maintain the bones.
D
Disorders of the kidneys always involve the __ and the __.
heart
skeleton
Foods get their energy from the sun: indirect vs direct
indirect: in the case of animals that eat plants
direct: in the case of photosynthesizing plants that make carbohydrate
How does the body maintain its 98.6 degree temperature?
by regulating the rates at which the metabolic reactions release heat energy
The cells must maintain themselves and some may have to reproduce and to do this they have to have their essential nutrients available including:
- energy nutrients
- vitamins
- water
- minerals
During severe stress to the body, metabolism __, which is why fever develops sometimes.
speeds up
An accelerated metabolism means:
the fuels are being used at a rate more rapid than normal
An accelerated metabolism may lead to:
Wasting of body organs and loss of weight (including loss of vital lean tissue)
The building up of body compounds is know as ___
anabolism
The breaking down of body compounds is know as ___
catabolism
Energy is stored in foods and in the body as ___ energy
chemical
___ is the sum total of all the chemical reactions that the body uses to obtain or expend energy from foods.
energy metabolism
What are the three energy yielding nutrients:
carbohydrates, fats, and proteins
What do the 3 energy yielding nutrients break down into?
- carbohydrates: glucose
- fat (triglycerides): glycerol and fatty acids
- proteins: amino acids
When ATP breaks down and releases one of its phosphate groups, what happens?
A small amount of energy is released and used in the body to build compounds.
With the loss of the phosphate group, ATP becomes ___.
ADP (adenosine diphosphate)
Who is ATP created from ADP?
by attaching a phosphate group to ADP.
The breakdown of glucose (a 6-carbon compound) into two molecules of ___, is called glycolysis, and produces TWO usable ATP.
pyruvate (a 3-carbon compound)
As the Carbons in glucose are broken apart to produce pyruvate, the hydrogens are transferred by ___ to the ETC.
coenzymes
The reactions of glycolysis produce a ___ amount of ATP, pyruvate, and hydrogen-rich coenzymes that are used later in energy metabolism.
small
After glycolysis, pyruvate is converted to ___ ___, which is a 2-carbon fragment and a coenzyme called CoA.
acetyl CoA
the TCA cycle name is ___ and it includes the breakdown of energy nutrients (enzymes break down acetyl CoA molecules)
tricarboxylic acid
Final step in energy metabolism is the ____
ETC!!! electron transport chain
What happens in the ETC, the last step in energy metabolism?
- a phosphate group is added to ADP to produce ATP
- the hydrogen atoms that were collected by coenzymes provide the chemical energy that drives ATP production
- the same Hydrogen atoms are linked w O2 to produce water.
The production of ATP via the ETC requires oxygen in the final step and is called ___.
aerobic metabolism
Glycolysis produces ATP without oxygen and is therefore called ____
anaerobic metabolism
glucose can be produced from several other compounds in a process called ___
gluconeogenesis
Any compound that can be converted to pyruvate ___ be used to make glucose. (CAN OR CAN’T)
CAN
Any compound that had been converted to acetyl CoA ___ be used to make glucose. (CAN OR CAN’T)
CAN’T
___ cannot be used to make glucose, but the __ portion of a triglyceride can be converted to pyruvate and then yield glucose.
Triglycerides
glycerol portion
The primary role of amino acids is to:
maintain supplies of needed body proteins
If amino acids are needed for energy or if they are consumed in excess, they first undergo ____.
deamination
a reaction in which amino acids are stripped of their nitrogen
deamination
The principal nitrogen-exertion product of metabolism is ___
urea
protein/fat is a efficient source of glucose when carbohydrate is not available?
protein!!!
A net excess of energy is almost all stored in the body as ___
fat in adipose tissue
___ both delivers calories and encourages storage of body fat.
alcohol
Fat os stored as ___.
adipose tissue
Excess energy intake from carbs, proteins, fats, and alcohol leads to storage of ___ ___.
body fat.
The cellular work when a person sleeps makes up ___ of the total energy a sedentary person expends in a day.
2/3rds
The nervous system and red blood cells cannot use ___, and instead need ___ for energy.
fatty acids
glucose
In the first few days of a fast, __ make sup 90% of the needed glucose, and __ produces about 10%.
- body protein
- glycerol
acidic, water-soluble compounds produced by the liver during the breakdown of fat when carbohydrate is not available
ketone bodies
During fasting, the nervous system shifts to partial dependent on ___ for energy.
ketone bodies
T/F: Mental alertness is not diminished during fasting.
True
4 changes in body during fasting:
- wasting of lean tissues
- impairment of disease resistance
- lowering of body temperature
- disturbances of the body’s fluid and electrolyte balances
When food energy intake equals energy expenditure, a person is in __ __.
energy balance
Change in energy stores equation:
change in energy stores= energy in (kcalories) - energy out (kcalories)
The body expends energy in two major ways to fuel its __ __ and to fuel its __ __.
- basal metabolism
- voluntary activities
__ __ supports the bodies work that goes on all of the time without a person’s conscious awareness.
Basal Metabolism
___ is the rate at which the body expends energy for these life-sustaining activities.
-taken after a 12 hour fast and restful sleep
BMR - basal metabolic rate
___ is a measure of the energy used of a person at rest in a comfortable setting.
RMR - resting metabolic rate
BMR is highest in people who are:
growing and have considerable lean body mass.
The # of calories spent on voluntary activities depends on 3 factors:
muscle mass, body weight, and activity
- An estimation of the energy required to process food.
- Also, this is a cellular activity that produces heat.
- Represents about 10% of total food energy taken in.
thermic effect of food
What gender has a lower BMI?
women; because men typically have more lean body mass.
BMR is high in short or tall people? Why?
tall because they have a larger surface area
The body’s weight reflects its ___ (the proportions of its bone, muscle, fat, fluid, and other tissue)
composition
The most variable tissues is ___
body fat
__ is an index of a person’s weight in relation to height.
BMI (body mass index)
BMI formula=
-weight (kg) divided by height (m)^2
OR
-weight (lb) divided by height (in)^2 x 703
BMI ranges: underweight, healthy weight, overweight, and obese
- underweight: below 18.5
- healthy weight: 18.5 and 24.9
- overweight: above 25
- obese: over 30
- Fat that is stored within the abdominal cavity in association with the internal abdominal organs
- Also called Subcutaneous fat
visceral fat
- Excess fat around the trunk of the body.
- also called “upper body fat”
central obesity
Hormones released by adipose tissue
Adipokines
A reason for why fat int he abdomen may increase the risk of disease involved ___
Adipokines
Adipokines help to regulate ___ and energy metabolism in the tissues.
inflammation
__ fat makers the “apple” profile of central obesity, and __ fat makes the “pear” shape around hips and thighs.
- visceral
- subcutaneous
A persons ___ ___ is a good indicator of fat distribution and central obesity.
waist circumference
A clinical estimate of total body fatness in which the thickness of a fold of skin on the back of the arm, below the shoulder blade, or in other places is measured with a caliper.
skinfold measure
Guidelines for Identifying those at risk for obesity relies on 3 indicators:
- a person’s BMI
- waist circumference
- a person’s disease risk profile
