9.1 Why do we need to eat?

Question 1

What are the two reasons we need to eat?

Answer 1

1) Growth, repair and maintenance
2) Energy

Question 2

What is food? What is nutrients? What are the 6 nutrients required for our body and how does it relate to growth and maintenance?

Answer 2

Food (substances consumed for nutriental support) which contains nutrients.

NUTRIENTS: Chemicalls that an organisms must obtain by its environment to survive
–> Raw materials for growth
–> Sources of energy

6 NUTRIENTS NEEDED FOR OUR BODY:
1) Carbohydrates
2) Protiens
3) Water
4) Minerals
5) Lipids
6) Vitamins
—> Necessary to build bones, muscles, cells, etc

Question 3

What is energy and how is it relevant to food?

Answer 3

Energy = Fuel that is needed for all biological processes, humans need chemical energy (which is obtained by food)

Question 4

What are factors that affect energy?

Answer 4

1) Endothermic or Ectothermic
-> Endo = WARM blooded, more energy required to maintain body temperature
-> Ecto = COLD blooded, less energy uses because body temperature is cooler.

What makes an organism loose body temperature?
-> Environment, constantly transferring body temperature to the environment because our body temperature is usually higher than the environemnt

2) Size
-> Large animals require mroe energy to live than small anmials
(Large animals usually eat more food)

EXCEPTION: smaller endothermic animals require more energy than larger ecto thermic animals.

Question 5

What is metabolism? How can it be broken down (2)? What are the functions of the two?

Answer 5

Metabolism: The many chemcial reactions/process that convert stored energy into usuable forms of chemical energy, happening within speicifc areas.

Catabolism:
Breaking down materials in an organisms (Large molecules into subunits)
(Can be both physical or chemical) (Digestion)

Anabolism:
Building larger and complex molecules from a simple molecule.
-> The production of a large molecule (Growth and repair)

Question 6

What is metabolic rate? What is it affected by? (5)

Answer 6

The rate of your metabolism. How fast is your body converting stored energy into working energy?

Affected by…
1) age (Older, metabolic rate goes lower = you are slower and convered stored energy into working energy)
2) height/size (Bigger = eats more)
3) gender/sex (Men are usually bigger with more muscle while women has a higher fat content)
4) physical activity
5) heredity (Naturally high due to preexposer or family history)

Question 7

What is BMR?

Answer 7

Basal Metabolic rate
-> The minimum amount of energy required to keep you alive (Only doing vital processes)

-> Ie: Sleep requires energy