fuck you 3.1-3.5

biological system

group of interacting components that work together to preform specific functions

how do plants fit the definition of a biological system

plants contain interacting structures that processes that work together for growth, reproduction, and survival

what factors influence plant growth

light, water, temp, nutrients, and CO2

what factors influence plant reproduction

pollinators, light, temp, water availability

what factors influence plant survival

water availability, disease, competition, temp, nutrients

what are the main components of the human respiratory system

nose, trachea, bronchi, bronchioles, lungs, alveoli, diaphragm

what are the main components of the human circulatory system

heart, blood vessels, blood

what is the function of the thylakoid membrane

site of the light-dependent reactions

what is the function of chlorophyll

absorbs light energy

what is the function of the stroma

site of the calvin cycle

Why are chloroplasts efficient for photosynthesis?

Their membrane systems increase surface area and organize reactions efficiently

what is the function of the trachea

conducts air to the lungs

What is the function of bronchi and bronchioles

carry air into the lungs

What is the function of alveoli?

gas exchange

What is the function of the diaphragm?

Changes thoracic volume for breathing

what is produced in light-dependent reactions

ATP, NADPH, and O2

How is ATP synthesized in photosynthesis?

proton gradients drive ATP synthase

How is NADPH synthesized

electrons reduce NADP+ to NADPH

why are membranes important in light-dependent reactions

membranes separate H+ concentrations to create proton gradients

what is the function of the calvin cycle

fixes CO2 into organic molecules

what molecule accepts CO2 in the calvin cycle

RuBP

what enzyme fixes CO2 in the calvin cycle

RUBISCO

what are the products of the calvin cycle

carbohydrates and regenerated RuBP

what is photorespiration

RUBISCO binds O2 instead of CO2 wasting energy

in what environments is photorespiration more likely

hot, dry, high-light environments

why do hot environments increase photorespiration

stomata close, reducing CO2 availability

what is the first stable product in C3 photosynthesis

A 3-carbon molecule

what is the purpose of C4 photosynthesis

reduce photorespiration

what enzyme initially fixes CO2 in C4 plants

PEP carboxylase

why does PEP carboxylase help reduce photorespiration

it does not bind O2

how is RUBISCO restricted to acting as a carboxylase in C4 plants

CO2 is concentrated around RUBISCO in bundle sheath cells

what is kranz anatomy

specialized arrangement of mesophyll and bundle sheath cells in C4 plants

what does phylogeny show about C4 evolution

C4 photosynthesis evolved independently multiple times

what type of evolution is shown by repeated evolution of C4 photosynthesis

convergent evolution

why are alveoli efficient for gas exchange

large surface area, thin walls, moist surface, rich blood supply

why are capillaries efficient for gas exchange

thin walls and short diffusion distance

how does ventilation improve gas exchange

maintains concentration gradients

what is hemoglobin

oxygen-carrying protein in red blood cells

how many polypeptide chains does hemoglobin contain

four

what is the cooperativity in hemoglobin

binding of one O2 increases affinity for additional O2

why is cooperativity important

allows efficient oxygen loading and unloading

why is the oxygen dissociation curve sigmoid-shaped

due to cooperativity

What happens to hemoglobin saturation in the lungs?

saturation increases

What happens to hemoglobin saturation in tissues?

oxygen is released

What happens to hemoglobin affinity when pH decreases?

affinity decreases

what causes lower pH in tissues

increased CO2 production

what happens to the oxygen dissociation curve at low pH

shifts right

what is the bohr effect

lower pH promotes oxygen release from hemoglobin