BIOS 1108 Module 4 Learning Objectives

phototrophs

organisms that obtain energy from sunlight

chemotrophs

organisms that obtain energy from chemical compounds

autotrophs

organisms that can fix inorganic carbon into organic molecules

heterotrophs

organisms that must obtain carbon but organic compounds

photoautotrophs

uses sunlight for energy and CO2 for carbon

chemoheterotrophs

use organic compounds for both energy and carbon

chemoautotrophs

use inorganic chemicals for energy and CO2 for carbon

photoheterotrophs

use sunlight for energy but require organic carbon sources

essential nutrients

required for survival; cannot be synthesized by the organism; must be obtained from the environment

beneficial nutrients

stimulate growth and development but are not strictly required or can be substituted by other nutrients

macronutrients

required in large amounts

examples of macronutrients for plants

carbon, nitrogen, phosphorus, and potassium

examples of macronutrients for animals

carbohydrates, proteins, and fats

micronutrients

required in trace amounts

examples of micronutrients for plants

iron and zinc

example of micronutrients in animals

vitamins and minerals (such as calcium and iron)

insufficient nutrients in plants

stunted growth, yellowing leaves (chlorosis), and poor fruit development

insufficient nutrients in animals

deficiency diseases (scurvy from lack of vitamin C)

excessive nutrients in plants

toxicity, nutrient imbalances, and inhibited growth

excessive nutrients in animals

toxicity, organ damage (iron overload)

diffusion definition

passive movement of molecules from high to low concentration without energy

facilitated diffusion definition

passive movement of molecules through protein channels; no energy required

ion channels definition

protein channels that allow specific ions to pass through the membrane passively

active transport definition

movement of molecules against their concentration gradient using energy (ATP)

proton pumps definition

use ATP to pump protons (H+) across a membrane, creating an electrochemical gradient

co-transport definition

movement of two molecules simultaneously; one molecule moves down its gradient, providing energy to move the other molecule against its gradient

diffusion’s role in nutrient acquisition

allows small non-polar molecules (oxygen, carbon dioxide) to cross membranes passively

facilitated diffusions/ion channels role in nutrient acquisition

enable polar or charged molecules (glucose ions) to cross membranes passively

active transport’s role in nutrient acquisition

move nutrients (amino acids and ions) against their concentration gradient into cells

proton pumps role in nutrient acquisition

create a proton gradient used to drive co-transport of nutrients (sucrose in plants)

co-transport’s role in nutrient acquisition

uses the energy from one molecule moving down its gradient to transport another molecule against its gradient (sodium/glucose co-transport in animal intestines)

importance of surface area in nutrient acquisition

larger surface area increases the rate of nutrient absorption

examples of larger surface area increasing the rate of nutrient absorption

root hairs in plants and microvilli in animal intestines

importance of distance in nutrient acquisition

shorter distances increase the rate of diffusion

examples of how shorter distances increases the rate of diffusion

thin cell membranes and close proximity of capillaries to nutrient absorption sites

importance of concentration gradients in nutrient acquisition

steeper gradients increase the rate of diffusion

examples of how steeper gradients increase the rate of diffusion

proton pumps in plant roots create gradients to drive nutrient uptake

what are the essential macronutrients required by plants

carbon, nitrogen, phosphorus, and potassium

what are the essential macronutrients required by animals

carbohydrates, proteins, fats, and vitamins and minerals

what is carbohydrates role as an essential macronutrient required by animals?

primary source of energy and organic carbon

what is proteins role as an essential macronutrient required by animals?

provide essential amino acids and nitrogen

what is fats role as an essential macronutrient required by animals?

provide energy, aid in vitamin absorption, and are used in hormone production

what are vitamins/nutrients role as an essential macronutrient required by animals?

required in small amounts for metabolic processes

what is carbon’s role as an essential macronutrient required by animals?

used to make glucose and cellulose; obtained from CO2 in the air

what is nitrogen’s role as an essential macronutrient required by animals?

part of proteins, nucleic acids, and vitamins; often a limiting factor for growth

what is phosphorus’s role as an essential macronutrient required by animals?

necessary for nucleic acids, phospholipds, and ATP; often a limiting factor

what is potassium’s role as an essential macronutrient required by animals?

regulates stomatal opening and closing; important for water balance

how do plants acquire nitrogen?

obtained from soil as nitrate (NO3-) or ammonium (NH4+)

how do plants use nitrogen?

used in proteins, nucleic acids, and vitamins

how do plants obtain phosphorus?

obtained from soil as phosphate ((PO4)3-)

how do plants use phosphorus?

used in nucleic acids, phospholipids, and ATP

how do plants obtain potassium?

obtained from soil as potassium ions (K+)

how do plants use potassium?

regulates stomatal function and water balance

how do animals obtain carbohydrates?

obtained from plants or animal sources

how do animals use carbohydrates?

broken down into glucose for energy

how do animals obtain proteins?

obtained from dietary sources (meat and plants)

how do animals use proteins?

broken down into amino acids for protein synthesis

how do animals obtain fats?

obtained from dietary sources (oils and animal fats)

how do animals use fats?

used for energy storage, hormone production, and cell membranes

what are some adaptations that increase surface area for nutrient absorption in plants

root hairs and mycorrhizae

what are some adaptations that increase surface area for nutrient absorption in animals

microvilli and villi

root hairs

increase surface area for water and nutrient absorption from soil

mycorrhizae

fungal associations that enhance nutrient uptake

microvilli

finger-like projections in the small intestine that increase surface area for nutrient absorption

villi

folds in the intestinal lining that increase surface area

what is the role of proton pumps in nutrient acquisition in plants

1. use ATP to pump protons (H+) out of root cells into the soil

2. create a proton gradient that drives the uptake of nutrients via co-transport

3. essential for maintaining nutrient uptake against concentration gradients

describe the formation of soil

soil forms through weathering of rock by mechanical (physical breakdown), chemical (dissolution/reactions), and biological (organism) processes over long periods of time (200-1000 years per inch)

describe the structure of soil

humus (5%), inorganic minerals (40-45%), and water/air (50%)

humus

organic matter (living/dead plants, microorganisms)

inorganic minerals

rock fragments (sand, silt, clay)

water/air

pore spaces filled with water and gases

what are some factors that influence formation

parent material (bedrock/sediment), climate (temperature/moisture), topography (slope/erosion), biological activity (root/microbes), and time

what are the types of soil textures

clay, sand, and loam

what are pros of clay when it comes to plant nutrient acquisition

high cation exchange capacity (holds positively charged ions tightly) and excellent water retention (which is good for drought prone areas)

what are cons of clay when it comes to plant nutrient acquisition

poor drainage and dense structure (hard for roots to penetrate)

what is a pro of sandy soil when it comes to plant nutrient acquisition

loose structure (easy root growth and oxygen flow)

what is a con of sandy soil when it comes to plant nutrient acquisition

low CEC (nurtients leach away quickly with water) and poor water retention (dries out fast)

what is a con of loam when it comes to plant nutrient acquisition

none

what is a pro of loam when it comes to plant nutrient acquisition

good water retention and drainage, there’s enough air pockets for roots, and holds nutrients well without binding them too tightly

what is the role of root hairs in nutrient acquisition

extensions of epidermal cells that increase surface area for absorption

what is the role of proton pumps in nutrient acquisition

use ATP to pump H+ into soil, creating a proton gradient

what are two types of proton pumps

use ATP to pump H+ to soil, creating a proton gradient

what is the role of cation exchange proton pumps in nutrient acquisition

H+ displaces cations from clay, allowing uptake via passive cation channels

what is the role of anion co-transport proton pumps in nutrient acquisition

H+ re-entry drives active transport of anions via co-transporters

what is the role of passive transport in nutrient acquisition

diffusion of cations down electrochemical gradient

what is the role of active transport in nutrient acquisition

energy-dependent uptake of anions against gradient

what are some adapations for nutrient acquistioin in plants

mycorrhizal fungi, Legume-Rhizobia Symbiosis, and carnivorous plants

what is the function of mycorrhizal fungi

increase surface area, decompose organic matter for nitrogen/phosphorous, and exchanges nutrients for plant sugars

what are the types of mycorrhizal fungi

ectomycorrhizae and endomycorrhizae

what is ectomycorrhizae

hypae wrap around root cells

what is endomycorrhizae

hyphae penetrate cell walls

the nodules in Legume-Rhizobia Symbiosis are

house nitrogen-fixing bacteria (rhizobia)

the nitrogenase in Legume-Rhizobia Symbiosis is

enzyme that converts N2 to NH3 (inhibited by O2, protected by leghemoglobin)

carniverous plants

digest insects for nitrogen, potassium, and phosphoruous in nutrient-poor soils

rhizobia’s role is

to fix atmospheric N2 into NH3 root nodules

rhizobia is (general or specific)

specific, only associates with legumes

benefit of rhizobia is

direct nitrogen supply, leghemoglobin protects nitrogenase

mycorrhizae is (general or specific)

general, associates with most plants

the role of mycorrhizae is to

decompose organic matter, releasing nitrogen and phosphorous, and extended root surface area

benefit of mycorrhizae is

enhanced water/nutrient uptake and protects against pathogens.