Why do we eat? What do we eat?

Question 1

We obtain the raw materials for growth and maintenance of our bodies from nutrients in food

Question 2

Nutrients

Answer 2

are the chemicals that an organism needs in order to grow, build, repair, tissues and make energy

Question 3

Nutrients that we need to stay healthy include

Answer 3

carbohydrates, fats, proteins, water, minerals, and vitamins

Question 4

Nutrients provided the energy that fuels all biological processes

Question 5

Cells use the chemical energy to fuel biological processes like physical activities such as growth and movement

Question 6

Endothermic animals(mammals, birds)

Answer 6

need a great deal of energy to keep their bodies warm and must consume more food than ectothermic animals(cold blooded) of equal size

Question 7

size:

Answer 7

another factor in determining how much an animal to eat(larger animals generally eat more food than smaller ones

Question 8

Metabolism is made up of catabolism and anabolism

Question 9

Catabolism

Answer 9

the metabolic reactions that breakdown larger molecules into smaller sub unites(protein->amino acids)

Question 10

Anabolism

Answer 10

is the building of larger more complex molecules from smaller simpler subunits(amino acids -> protein)

Question 11

Metabolic rate

Answer 11

metabolic rate refers to the rate at which our body converts stored energy into walking energy

Question 12

Factors affecting metabolic rate:

Answer 12

-Body size: the larger the body, the more energy required to stay alive

-Physical activity: muscle burns more energy than far so physical activity requires more energy

-Sex: makes are typically larger in size and have more muscle mass than females of the same size, age, and fitness level

-Age: metabolic rate decreases with age(part due to less physical activity and loss of muscle mass)

-Genetics: some people have a naturally higher metabolic rate

Question 13

energy is measured in…

Answer 13

Joules(J)

Question 14

We see energy on our foods measure in calories

Question 15

Basal metabolic rate

Answer 15

the minimum amount of energy required to keep you alive. This is the amount of energy you wouldn’t need to use per day if you stayed in bed all day with your body only performed vital processes (breathing, heartbeat)

Question 16

Carbohydrates

Answer 16

-Primary source of energy
-Made up of carbon, hydrogen, and oxygen
-3 types: Monosaccharides, disaccharides, and polysaccharides

Question 17

Monosaccharides

Answer 17

-Most basic/shape or simple sugars(fructose, galactose, glucose)
-Glucose is needed for cellular respiration to provide energy for physical activity and cellular processes
-Found in fruits, milk and things like cake, candy and refined sugar products

Question 18

Disaccharides

Answer 18

double sugars: result of 2 monosaccharides joining together(maltose, sucrose)

Question 19

Polysaccharides

Answer 19

complex: result of 3 or more monosaccharides linking together
-need to be digested before we can absorb them
-Some are used for energy stored in plants(startch) and glycogen(in animals)
-Some are structural(cellulose in plant cell and chitin in exoskeletons of insects)

Question 20

Dietary sources of carbohydrates

Answer 20

-Grains, potatoes, breads, fruits
-A healthy diet generally is considered to be one in which carbohydrates provide at least 55% of a persons energy needs
-In humans carbs are stored in the liver as glycogen
-When we have reached the max amount of glycogen storage, excess carbs are converted into lipids and stored as fat
-When energy is needed, glycogen is converted into useable glucose

Question 21

Protiens

Answer 21

-The functional molecules and “building blocks of life”
-Help chemical reactions take place(enzymes)
-Repair and maintain the cell
-Transport materials around the body(hemoglobin)
-Some serve as hormones-chemical messengers released by all cells in the body which influence cell activity elsewhere in the body

Question 22

Protiens are involved in

Answer 22

movement, structure(muscle, connective tissue, hair, nails), defence system(antibodies made by immune system), and a source of energy

Question 23

Protiens are made up of…

Answer 23

• amino acids
  -there are 20 amino acids (12 are made by our body, 8 we must obtain from our diet)
• these are called essential amino acids
  -Protien can be found in meat, eggs, fish, beans, lentils, and nuts
  -Candy suggests that 10-30% of energy requirements should come from protien

Question 24

Lipids(Fats)

Answer 24

-Concentrated source of chemical energy for the body
-Functions: structural components of cell membranes, some hormones(sex chromosomes), and insulation
- Made up of 3 fatty acids bonded to a glycerol molecule called a triglyceride
-Some fatty acids are essential(omega-3 fatty acid is an example which is needed for preventing health problems like heart diseases and arthritis)
-Lipids should constitute no more than 30% of energy intake

Question 25

Triglycerides can be either..

Answer 25

saturated or unsaturated saturated: are solid at room temperature(meat, butter) unsaturated: are liquid at room temperature(oil), these are called good fats

Question 26

Water

Answer 26

-needed fr chemical reactions, helps digest food, maintain blood volume, and navigate body temperature -you must drink about 2L of water a day

Question 27

Vitamins

Answer 27

-A compound that an organism needs as a nutrient in only small amounts -Needed to regulate cell functions, growth and development -Can be fat soluble(Vitamin A,D,E, and K) or water soluble(vitamin B and C) -Nost see obtained from food, some can be also produced in the body (body turns beta carotene into Vitamin A; Vitamin D made when our skin is exposed to sun light)

Question 28

Minerals

Answer 28

-Naturally occurring elements that our body uses to carry out metabolic processes and to build on repair tissues -Calcium absorption phosphorus are critical in bone formation -Iron is a component of hemoglobin

Question 29

Maintaining a balance

Answer 29

To maintain a healthy life style, we should -Have a moderate level of physical activity -Eat the appropriate amount of food -Eat a variety of food