Systems: macromolecules and subunits

SBI3U (Secours) - first part of the digestive systems hyperdoc

Besides oxygen, the other reactant necessary for cellular respiration is ______

Glucose

Chemical formula of Glucose

C₆H₁₂0₆

Formula for cellular respiration

C6H12O6 + 6O2 → 6CO2 + 6H2O + 38ATP

Why do we eat? (2 reasons)

• Obtain energy from food (mostly glucose for cellular respiration)

• Obtain nutrients to build tissues and keep metabolic processes functioning

to make hemoglobin, you need what nutrient in your diet?

Iron

Macromolecules

The 4 main nutrients you need in your diet, they are large molecules and must be digested in their subunits in order to be absorbed

The 4 main macromolecules + examples of sources

1. Carbohydrates (potatoes, rice, pasta, bread)

2. Proteins (meat, eggs, cheese, legumes)

3. Lipids (meat, cheese, nuts)

4. Nucleic Acid (all foods)

Carbohydrates

The main source of energy for cells
⇨ composed of simple sugars linked together

The various forms of carbohydrates (3)

1. Monosaccharides: single carbon ring (SIMPLE)

2. Disaccharides: 2 carbon rings linked together (SIMPLE)

3. Polysaccharides: hundreds of simple sugars lined up in a chain (COMPLEX)

Examples of Monosaccharides

Glucose, Fructose (same chemical formula as glucose), Galactose

Examples of Disaccharides

Maltose, Sucrose, Lactose

Examples of Polysaccharides

Starch, Cellulose, Glycogen

Starch

• Made by plants

• Broken down into Glucose by digestive system

• Found in fruits, veggies (potatoes), cereals and pasta

Cellulose

• Forms the main structure of the cell wall

• Not digestible by humans but useful in the intestines as fiber

Cellulose constitutes ___ to ___% of terrestrial plant biomass

35 to 50%

Glycogen

• Stored in muscles and liver

• Used by animals (and fungi) to store chemical energy

• Helps quickly release glucose into the blood

Proteins

building blocks of structural molecules, enzymes, hemoglobin, certain hormones, antibodies, etc

Proteins are made up of subunits called

amino acids

Amino acids are linked together by ____ to form long strands, which make up ___

peptide bonds, proteins

Your cells need a _________ supply of _______ _____ to build all the different protein molecules

regular, amino acids

There are __ total types of amino acids; __ are essential and __ are nonessential

20, 9, 11

Essential vs Nonessential amino acids

Essential = obtained via food
Nonessential = produced by the cells

Lipids (5 uses)

• used to store energy⚡

• helps absorb fat-soluble vitamins (ADEK) 🐟

• builds cell membranes 🔨

• produces hormones 💊

• provides insulation 🧥

How does the energy provided by lipids compare to sugar?

by mass, lipids provide 2x as much energy as sugar

Phospholipids

type of lipid that forms the cell membrane
⇨ composed of a hydrophilic head and two hydrophobic tails

Triglycerides

The main type of fat
⇨ composed of 3 fatty acid chains attached to a single glycerol molecule

Saturated vs Unsaturated fatty acids

Saturated: single bonds, straight and tightly packed structure (usually solids)

Unsaturated: double bonds, bent and looser structure (usually liquids)

Nucleic Acids

used in the formation of DNA during Interphase’s S-phase

The subunits of Nucleic Acids are _________, which consist of a sugar, a nitrogenous base, and a phosphate group

Nucleotide