Nutrition

Question 1

Materials to Grow

Answer 1

all living things require a source of energy and a source of carbon

Question 2

Photoroph

Answer 2

obtain energy from sunlight

Question 3

Chemotroph

Answer 3

obtain energy from chemical compounds

Question 4

Autotroph

Answer 4

organisms that fix (reduce) inorganic carbon like CO2

Question 5

Heterotroph

Answer 5

organisms that obtain carbon from organic compounds

Question 6

Photoautotroph

Answer 6

obtain energy from sunlight and carbon from CO2

Question 7

Chemoautotroph

Answer 7

obtain energy from inorganic compounds and build their complex molecules from CO2

Question 8

Photoheterotroph

Answer 8

obtain energy from sunlight and carbon from an organic carbon source

Question 9

Chemoheterotroph

Answer 9

obtain energy and carbon from an organic chemical source

Question 10

Essential Nutrient

Answer 10

nutrient that an organisms CANNOT synthesize and must acquire from another source

Question 11

Beneficial Nutrient

Answer 11

nutrient that stimulates growth and development but is NOT REQUIRED and/or could be substituted by another nutrient

Question 12

Macronutrients

Answer 12

essential nutrients that are required in large amounts
- Carbon
- Nitrogen
- Hydrogen
- Oxygen
- Phosphorus
- Sulfur
- Also includes potassium, magnesium, calcium, and sodium

Question 13

Micronutrients

Answer 13

essential nutrients required in smaller amounts
- EX: iron in electron-transport reactions

Question 14

Macronutrients: CARBON

Answer 14

the major element in ALL macromolecules (carbohydrates, lipids, proteins, nucleic acids)
- accounts for ~%50 of cell composition

Question 15

Macronutrients: NITROGEN

Answer 15

• 12% of the total dry weight of a cell
• in proteins, nucleic acids, and other cell constituents
• most nitrogen is available in nature in an atmospheric (N2) or inorganic form
• must be converted into an organic form by nitrogen-fixing organisms

Question 16

Macronutrients: H + O

Answer 16

part of many organic compounds and water

Question 17

Macronutrients: PHOSPHORUS

Answer 17

required by all organisms for the synthesis of nucleotides + phospholipids

Question 18

Macronutrients: SULFUR

Answer 18

• part of the structure of some amino acids
• present in several vitamins and coenzymes

Question 19

Nutritional Needs of Plants

Answer 19

require light, water, and ~20 essential nutrients:
- Carbon
- Nitrogen
- Phosphorus
- Potassium

Question 20

Plants: Carbon

Answer 20

• obtained from the air to make glucose, which is used to construct cellulose
• cellulose is the main structural component of the cell wall + most abundant organic compound on Earth

Question 21

Plants: Nitrogen

Answer 21

• parts of proteins + nucleic acids, and used in the synthesis of some vitamins
• atmospheric nitrogen is not biologically avaiibale due to the triple bond in N2
• atmospheric nitrogen must be “fixed” by specific bacteria to make it bioavailable
• OFTEN A LIMITING FACTOR FOR PLANT GROWTH

Question 22

Plants: Phosphorus

Answer 22

necessary to synthesize nucleic acids + phospholipids
- in ATP, turns food energy into chemical energy through oxidative phosphorylation
- phosphorylation in photosynthesis turns light into chemical energy
- typically must be “fixed” to be bioavailable
- LIMITING FACTOR FOR PLANT GROWTH

Question 23

Plants: Potassium

Answer 23

role in regulating stomatal opening and closing
- as they open for gas exchange, stomata help maintain a healthy water balance
- potassium ion pumps support this process
- may be present at lower concentrations in some soils
- COMMON LIMITING FACTOR FOR PLANT GROWTH

Question 24

Nutrient Deficiences

Answer 24

occur when a plant or animal does not have enough of a nutrient to support the biological functions performed by the nutrient

Question 25

Nutrient Excessiveness

Answer 25

can be toxic to certain tissues/cell types

Question 26

Nutritional Needs of Animals

Answer 26

- require CHONPS as building blocks for biological molecules - animals are CHEMOHETEROTROPHS - obtain energy and nutrients from carbohydrates, proteins, and fats

Question 27

Herbivores

Answer 27

animals whose primary food source is plant-based - they have evolved digestive systems capable of handling large amounts of plant material, which require additional processing steps

Question 28

Frugivores

Answer 28

fruit eaters (herbivores)

Question 29

Granivores

Answer 29

seed eaters (herbivores)

Question 30

Nectivores

Answer 30

nectar feeders (herbivores)

Question 31

Folivores

Answer 31

lead eaters (herbivores)

Question 32

Carnivores

Answer 32

animals that primarily eat other animals

Question 33

Omnivores

Answer 33

animals that eat plants and animals

Question 34

Animals: Carbohydrates

Answer 34

primary source of organic carbon for omnivores and herbivores; carnivores rely on proteins and lipids as carbon sources

Question 35

Animals: Proteins

Answer 35

dietary sources of nitrogen and sulfur (and carbon for carnivores)

Question 36

Animals: Fats

Answer 36

significant sources of chemical energy (better than carbohydrates) - dietary fats are necessary to aid the absorption of fat-soluble vitamins and the production of fat-soluble hormones

Question 37

Animal Essential Nutrients

Answer 37

must be eaten; four classes: 1. Essential Amino Acids 2. Essential Fatty Acids 3. Vitamins 4. Minerals

Question 38

Essential Amino Acids

Answer 38

necessary as protein building blocks - for humans all essential AA are in meat sources - vegetarians and vegans must eat sufficient quantities of grain and legume proteins sources

Question 39

Essential Fatty Acids

Answer 39

necessary as fat building blocks (and signaling molecules) - for humans, there are only 2 essential FA - the rest we synthesize

Question 40

Vitamins

Answer 40

organic compounds needed in small amounts - water soluble: easily excreted in urine (vitamin C) - fat soluble: can accumulate in adipose tissue (vitamin D)

Question 41

Minerals

Answer 41

inorganic compounds needed in small amounts - Ca, K, Su, Ph, Iron

Question 42

Diffusion

Answer 42

molecules move from high to low concentration DOWN their concentration gradient - no energy used

Question 43

Facilitated Diffusion

Answer 43

diffusion that occurs through a protein channel in a cell membrane (highly specific) - used for polar and large molecules to cross the nonpolar cell membrane - does not use energy - molecules move DOWN their CG

Question 44

Active Transport

Answer 44

movement of a molecules using energy to move it AGAINST its CG

Question 45

Proton Pumps

Answer 45

protein complexes that use ATP to pump protons from one side to the other of the membrane - creating an electrochemical gradient

Question 46

Electrochemical Gradient

Answer 46

high concentration of positive protons on one side of the PM - used as a source of energy to move other molecules AGAINST their concentration gradients via CO-TRANSPORTERS

Question 47

Co-Transport

Answer 47

movement of 2 molecules at the same time; one is moved DOWN its CG, which releases energy that is used to move another AGAINST its CG - occurs through highly specific protein channels called co-transporters

Question 48

Factors that Influence Nutrient Acquisition

Answer 48

1. Concentration Gradient 2. Distance 3. Surface Area

Question 49

FACTORS: Concentration Gradient

Answer 49

molecules naturally diffuse from high to low (energy is not required); the higher the CG is one either side of the membrane, the faster the rate of diffusion - plants use proton pumps to move protons into the soil to create a + ionic gradient to drive positive nutrients into roots - animal digestive tracts use gradients to move nutrients into the bloodstream

Question 50

FACTORS: Distance

Answer 50

diffusion rate is influenced by distance; the longer the distance, the slower the rate - Cnidarians only have 2 thin tissue layers - the capillaries in a circulatory system absorb nutrients from the digestive tract and move them to the blood stream

Question 51

FACTORS: Surface Area

Answer 51

the larger the SA, the more nutrients an organism can absorb - plant roots have root hairs that increase SA to absorb water and nutrients - mammalian digestive tracts have a folded lining + small intestine with microvilli