AP biology Big idea 2 review (biological systems utilize free energy and molecular building blocks to grow, to reproduce, and to maintain dynamic homeostasis)
Why do living organisms need each of the following elements: nitrogen, carbon, hydrogen, oxygen, phosphorus, sulfur
"First off, carbon enters easily into bonds with other carbon atoms. This means it forms vast chains that act as a nice skeleton for other atoms to bond to," Pasek said. In other words, carbon atoms are the perfect building blocks for large organic molecules. "This lends itself to complexity." But what explains the other five chemical ingredients of life? "One thing that makes nitrogen, hydrogen and oxygen good is that they're abundant," Pasek said. "They also exhibit acid-base effects, which allows them to bond with carbon to make amino acids, fats, lipids and the nucleobases from which DNA and RNA are built." "Sulfur provides electron shuffle," Pasek continued. "Basically, with their surplus of electrons, sulfides and sulfates help catalyze reactions. Some organisms use selenium in place of sulfur in their enzymes, but not many." Last but not least, phosphorus, usually found in the molecule phosphate, is vital to metabolism, because polyphosphate molecules such as ATP (adenosine triphosphate) are able to store a huge amount of energy in their chemical bonds. Breaking the bond releases its energy; do this enough times in, say, a group of muscle cells, and you can move your arm.
What is the definition of free energy in a biological system?
a thermodynamic quantity equivalent to the capacity of a system to do work
Krebs cycle
per turn: acetyl CoA becomes 2 CO2 3 NAD+ becomes 3 NADH 1 FADH becomes 1 FADH2 1 ADP becomes 1 ATP (substrate level phosphorylation) mitochondrial matrix 2 ATP substrate level phosphorylation 6 NADH 2 FADH2 begins with acetyl CoA ends with CO2 release of carbon atoms strip all electrons in C-H bonds most of the energy is released here
How does each of the following illustrative examples affect the stability of populations, communities, and/or ecosystems? Provide whether each of these is biotic or abiotic: water and nutrient availability availability of nesting materials and sites food chains and food webs species diversity population density algal blooms
water and nutrient availability: the more available, the more stable the ecosystem, abiotic availability of nesting: the more nesting available, the more stable the ecosystem, abiotic materials and sites: the more available, the more stable the ecosystem, abiotic food chains and food webs: the less interrupted, the more stable the ecosystem, biotic species diversity: the more diversity, the more stable the ecosystem, biotic population density: the more dense, the less stable the ecosystem, biotic algal blooms: the larger the bloom, the less stable the ecosystem, biotic
all of the properties of water that were discussed before are due to which properties of water?
water is polar
Explain how the following examples would result in changes to free energy availability. In each of these examples, describe what would happen to the ecosystem if these things happened: changes in the producer level changes in energy resource levels (such as sunlight)
-an increase in the producer level will lead to an increase in free energy availability -a decrease in the producer level will lead to a decrease in free energy availability -an increase in the energy availability will lead to an increase in availability of free energy -a decrease in the energy availability will lead to a decrease in availability of free energy
Describe how cell walls differ from cell membranes. Give examples of three different types of organisms that have cell walls and describe how they differ from each other.
1. Cell wall is found in plant cell and cell membrane is found in animal cells. 2. Cell membrane is covered by the cell wall which forms the outer most covering. 3. Cell wall is completely permeable whereas cell membrane is semi-permeable. 4. Cell wall is made up of cellulose and cell membrane is made up of lipids and proteins. 5. Cell membrane is also known as plasma lemma.
How does the conversion of adenosine triphosphate diphosphate result in the release of free energy?
ATP is linked together by two high-energy bonds. When one phosphate group is removed by breaking one of the bonds in a process called hydrolysis, energy from the bond is released and ATP is converted to ADP. Also, energy is released when a phosphate is removed from ADP to form AMP.
Explain why each of the following are illustrative examples of how organisms respond to changes in the environment. Be sure to include whether these changes are behavioral or physiological: photoperiodism and phototrophism in plants hibernation and migration in animals taxis and kinesis in animals chemotaxis in bacteria sexual reproduction in fungi nocturnal and diurnal activity circadian rhythms shivering and sweating in humans
Below is a summary of each of the things organisms respond to in the environment. photoperiodism: seasonal changes in day length, behavioral phototrophism: orientation towards light, behavioral hibernation: a state of inactivity for various mammals, behavioral migration: move to go to best feeding areas, behavioral taxis: movement of an organism in response to a stimulus, behavioral kinesis: animal's non-directional response to a stimulus, behavioral chemotaxis: movement of a motile cell or organism, or part of one, in a direction corresponding to a gradient of increasing or decreasing concentration of a particular substance. fungi: reproduce asexually by fragmentation, budding, or producing spores, physiological nocturnal/diurnal: awake either night or day, behavioral circadan rhythms: 24 hour cycle in the physiological body, physiological shivering and sweating: regulates temperature, physiological
Cell membranes consist of which five biochemical molecules? What are the functions of each?
Cell membranes consist of a structural framework of phospholipid molecules, embedded proteins, cholesterol, glycoproteins, and glycolipids. phospholipid: allows the cell membrane to be both hydrophobic and hydrophilic embedded proteins: they can be hydrophobic or hydrophilic cholesterol: keeps cell membrane fluid glycoproteins: play role in cell to cell interactions glycolipids: serve for recognition sites for cellular reactions
Explain each of the following mammalian immune responses that are specific towards a pathogen: cell mediated vs humoral role of cytotoxic T cells role of B cells and antibodies antigens vs antibodies antibody specificity initial pathogen exposure vs subsequent pathogen exposures (rate of response, role of memory cells)
Cell-mediated immunity is an immune response that does not involve antibodies, but rather involves the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen. Humoral immunity or humoural immunity is the aspect of immunity that is mediated by macromolecules found in extracellular fluids such as secreted antibodies, complement proteins, and certain antimicrobial peptides. ... Its aspects involving antibodies are often called antibody-mediated immunity. cytotoxic T cells: lymphocytes that destroy virus infected body cells and abnormal cells; destroy cells by attacking the cell's membrane and causing the cell the rupture antigens: a toxin or other foreign substance that induces an immune response in the body, especially the production of antibodies. antibody: protein made by plasma cells derived from B cells, has H and C regions, circulate in blood and lymph bind to specific antigen, mark foreign cell and molecules for destruction, antigen antibody complexes activate complement initial exposure: reaction takes a longer time because the humoral immunity response has to take place secondary exposure: reaction is very fast because the cells recognize the antigens on the invaders
What happens when acquired free energy exceeds free energy expenditures? What happens when free energy expenditures exceed the acquired free energy?
Excess acquired free energy versus required free energy expenditure results in energy storage or growth. Insufficient acquired free energy versus required free energy expenditure results in loss of mass and, ultimately, the death of an organisms
Explain the process by which heterotrophs capture free energy present in carbon compounds (both aerobically and anaerobically), which are produced by other organisms.
Heterotrophs capture free energy present in carbon compounds produced by other organisms. Heterotrophs may metabolize carbohydrates, lipids, and proteins by hydrolysis as sources of free energy. Fermentation produces organic molecules, including alcohol and lactic acid, and it occurs in the absence of oxygen.
Explain how the continuity of homeostatic mechanisms reflects common ancestry. How do different environmental conditions affect these mechanisms?
Human body include mechanisms that help regulate the body, this includes organs, glands, tissues and cells. The adjusting of these enables the body to constantly be in a steady state. The main mechanisms of homeostasis are body temperature, body fluid composition, blood sugar, gas concentrations, and blood pressure. The continuity of homeostatic mechanisms reflects common ancestry because the main mechanisms of homeostasis are similar throughout the various domains. This is also evident through homeobox genes. Homeobox genes are a large family of similar genes that direct the formation of many body structures during early embryonic development. A homeobox is a DNA sequence found within genes that are involved in the regulation of patterns of anatomical development morphogenesis in animals, fungi, and plants. Different environmental conditions affect these mechanisms either by stimulating them or inhibiting them, depending on the situation.
Elaborate on the following concepts that address how the induction of transcription factors during development results in sequential gene expression: homeotic genes embryonic induction temperature and water availability during seed germination genetic mutations and abnormal development genetic transplantation experiements linking gene expression and normal development genetic regulation of development and cellular control using micro RNAs
Induction of transcription factors during development results in sequential gene expression. Homeotic genes are involved in developmental patterns and sequences. Embryonic induction in development results in the correct timing of events. Temperature and the availability of water determine seed germination in most plants. Genetic mutations can result in abnormal development. Genetic transplantation experiments support the link between gene expression and normal development. Genetic regulation by microRNAs plays an important role in the development of organisms and the control of cellular functions.
contrast innate vs learned behaviors, and use them both to explain how individuals can act on information and communicate it with others
Innate behaviors are behaviors that are inherited. Learning occurs through interactions with the environment and other organisms. Individuals can learn information to help them in the real world but they can also use common sense from inherited behaviors to make proper decisions
How do internal cellular membranes facilitate cellular processes?
Internal membranes facilitate cellular processes by minimizing competing interactions and by increasing surface area where reactions can occur.
How do the membranes and membrane bound organelles differ between the three domains of life?
Membranes and membrane-bound organelles in eukaryotic cells localize (compartmentalize) intracellular metabolic processes and specific enzymatic reactions. Archaea and Bacteria generally lack internal membranes and organelles and have a cell wall.
Describe the process by which of the following molecules act as electron acceptors: NADP* O2
NADP+ is used in photosynthesis O2 is used in cellular respiration
Explain the evolution of photosynthesis in prokaryotic organisms. How did this lead to the evolution of eukaryotes and eukaryotic photosynthesis?
Of the three domains of life, Bacteria, Archaea, and Eukarya, chlorophyll-based photosynthesis has only been found in the bacterial and eukaryotic domains. The ability to do photosynthesis is widely distributed throughout the bacterial domain in six different phyla, with no apparent pattern of evolution. Overwhelming evidence indicates that eukaryotic photosynthesis originated from endosymbiosis of cyanobacterial-like organisms, which ultimately became chloroplasts (Margulis, 1992). So the evolutionary origin of photosynthesis is to be found in the bacterial domain. Significant evidence indicates that the current distribution of photosynthesis in bacteria is the result of substantial amounts of horizontal gene transfer, which has shuffled the genetic information that codes for various parts of the photosynthetic apparatus, so that no one simple branching diagram can accurately represent the evolution of photosynthesis (Raymond et al., 2002).
Describe the concept of negative feedback in terms of dynamic homeostasis and the maintenance of a physiological set point.
Organisms use negative feedback mechanisms to maintain their internal environments by returning the changing condition back to its target set point, while positive feedback mechanisms amplify responses.
Explain the method by which molecules are transported actively and passively across the cell membrane. Be sure to explain the role of metabolic energy and concentration gradients in your description.
Passive transport does not require the input of metabolic energy; the net movement of molecules is from high concentration to low concentration. Passive transport plays a primary role in the import of resources and the export of wastes. Membrane proteins play a role in facilitated diffusion of charged and polar molecules through a membrane. External environments can be hypotonic, hypertonic or isotonic to internal environments of cells. (examples - glucose transport, Na+/K+ transport) Activity transport requires free energy to move molecules from regions of low concentration to regions of high concentration. Active transport is a process where free energy (often provided by ATP) is used by proteins embedded in the membrane to "move" molecules and/or ions across the membrane and to establish and maintain concentration gradients. Membrane proteins are necessary for active transport.
Based on the cell membrane's selectively permeable nature, what kinds of molecules may pass freely through it? How do other molecules pass through?
Small, uncharged polar molecules and small nonpolar molecules, such as N2, freely pass across the membrane. Hydrophilic substances such as large polar molecules and ions move across the membrane through embedded channel and transport proteins. Water moves across membranes and through channel proteins called aquaporins.
How did the evolution of cell membranes lead to the origin of life?
The first cell is presumed to have arisen by the enclosure of self-replicating RNA in a membrane composed of phospholipids
Explain how phospholipids give cell membranes both hydrophilic and hydrophobic properties.
The hydrophilic phosphate portions of the phospholipids are oriented toward the aqueous external or internal environments, while the hydrophobic fatty acid portions face each other within the interior of the membrane itself.
Compare and contrast the concepts of endocytosis and exocytosis. Be sure to provide a comprehensive explanation that includes the role of specific organelles during each process.
The processes of endocytosis and exocytosis move large molecules from the external environment to the internal environment and vice versa, respectively. In exocytosis, internal vesicles fuse with the plasma membrane to secrete large macromolecules out of the cell. In endocytosis, the cell takes in macromolecules and particulate matter by forming new vesicles derived from the plasma membrane.
Explain why smaller cells have more favorable surface area to volume ratios. Provide a quantitative example of this.
The surface area must be large enough to adequately exchange materials; smaller cells have a more favorable surface area to volume ratio because of this
Describe each of the following examples of the highly ordered systems of life: order is maintained by constant free energy input into the system loss of order or free energy flow results in death increased disorder and entropy are offset by biological processes that maintain or increase order
This is talking about Gibbs Free Energy. The examples are basically asking what each of them mean in the equation. Please see image for more information.
Discuss why the following properties of water are necessary for living systems: cohesion, adhesion, high specific heat capacity, universal solvent, heat of vaporization, heat of fusion, thermal conductivity
Water is important because water is the solvent that transports many essential molecules and other particles around the body. These include nutrients and waste products from the body's metabolic processes. Particles such as some ions and molecules need to be able to move around biological organisms. cohesion: Cohesion holds hydrogen bonds together to create surface tension on water. adhesion: adhesion holds water to other things high specific heat capacity: Water has the highest specific heat capacity of any liquid. Specific heat is defined as the amount of heat one gram of a substance must absorb or lose to change its temperature by one degree Celsius. vaporization: Vaporization (or vapourisation) of an element or compound is a phase transition from the liquid phase to vapor. There are two types of vaporization: evaporation and boiling. heat of fusion: The enthalpy of fusion of a substance, also known as (latent) heat of fusion, is the change in its enthalpy resulting from providing energy, typically heat, to a specific quantity of the substance to change its state from a solid to a liquid at constant pressure. thermal conductivity: the degree to which a specified material conducts electricity, calculated as the ratio of the current density in the material to the electric field that causes the flow of current. It is the reciprocal of the resistivity.
Describe how surface area to ratio affects a biological system's ability to obtain necessary resources or eliminate waste products. How does this affect cell size?
a low surface area to volume ratio can slow the diffusion of necessary resources or waste products a high surface area to volume ratio can speed up the diffusion of necessary resources or waste products this means that cell size is smaller in order to have a high surface area to volume ratio
Fermentation
alcohol fermentation: converts pyruvate to ethanol bacteria and yeast do this, produces CO2 lactic acid fermentation: pyruvate is converted to lactic acid and NADH oxidized to make NAD+ fungi, bacteria and humans used in cheese and yogurt as well as muscles
Dark Reaction
anabolic fixes CO2 input: NADPH, ATP, CO2 output: G3P, ADP, NADP+ uses the NADPH/ATP from light reaction to make sugar to get one glucose: needs to occur 6 times with 6 CO2 three phases: carbon fixation, reduction, regeneration
How do each of the following cooperative behaviors contribute to the survival of multiple populations: availability of resources leading to fruiting body formation niche and resource partitioning mutualistic relationships biology of pollination
availability of resources: the more resources available, the more organisms can survive leading to fruiting: the more fruit available and bees available, the more fruiting can occur niche and resource partitioning: the more organisms have different niches, the more populations can survive mutualistic relationships: the better the relationship, the more the populations will survive pollination: the more bees and insects, the more pollination can occur
formation of acetyl CoA
begins with pyruvate 3 carbon pyruvate goes to transport protein CO2 is given off NADH+ enters and becomes NADH + H+ coenzyme A enters product is acetyl coenzyme A, 2 carbon
How does each of the following illustrative examples affect cellular activities? Provide whether each of these is biotic or abiotic: cell density biofilms temperature water availibility sunlight
cell density: the denser the cell, the harder it is to move products around cells, biotic biofilms: these can take energy away from a cell, which can decrease function, biotic temperature: some types of cellular activities work better under warm conditions and others work under cold conditions, abiotic water availability: cellular activities need water in order to function appropriately, abiotic sunlight: various processes need sunlight in order to carry out cellular activities, abiotic
Describe the intracellular metabolic processes and specific enzymatic reactions associated with each of the following membranes/membrane bound organelles: chloroplasts, endoplasmic reticulum, golgi body, mitochondria, nuclear envelope, ribosomes, vacuoles, vesicles
chloroplast: double membrane thylakoids grana stroma contains own DNA and ribosomes smooth ER: no ribosomes synthesis of lipids, metabolism of carbohydrates (glycogen hydrolysis) detoxification of drugs and poisons, stores calcium rough ER: with ribosomes synthesis of secretory proteins (glycoproteins, insulin) membrane production golgi apparatus: a complex of vesicles and folded membranes within the cytoplasm of most eukaryotic cells, involved in secretion and intracellular transport. double membrane these are found in both plant and animal cells mitochondria: cellular respiration double membrane (phospholipids) cristae/matrix intermembrane space contains own DNA and ribosomes all mitochondria come from mom nuclear envelope: the phospho lipid bilayer membrane which surrounds the genetic material and nucleolus in eukaryotic cells free ribosomes: makes proteins that function in the cytosol bound ribosomes: makes proteins destined for membrane insertion, package or export from the cell vacuole: a space or vesicle within the cytoplasm of a cell, enclosed by a membrane and typically containing fluid single membrane this is found in both plant and animal cells
how do the following animal physiological events involve interactions between internal/external signals and environmental cues: circadian rhythms diurnal/nocturnal and sleep/wake cycles seasonal responses (hibernation, estivation, migration) release and reaction to pheromones visual displays in the reproductive cycle jet lag
circadian rhythms: the body naturally has a 24 hour physiological cycle based on the environment diurnal/nocturnal sleep cycles: various organisms are more awake during the day or more awake during the night based on the environment and niches included seasonal responses: various organisms undergo hibernation, estivation or migration depending on the environmental stimuli pheromones: various organisms will have varying responses to pheromones released by organisms in response to environmental stimuli reproductive cycle: the reproductive cycle runs depending on environmental stimuli jet lag: we all react to jet lag because the change in environment messes with our circadian rhythms
glycolysis breakdown
cytoplasm forms 2 ATP substrate level phosphorylation 2 NADH begins with 6 carbon glucose ends with 2 3 carbon pyruvates rearrange of carbon atoms anaerobic fermentation oldest
How do each of the following illustrative examples provide evidence that disruptions at the molecular and cellular levels affect the health of an organism: dehydration immunological responses to pathogens, toxins and allergens
dehydration- this happens because of water potential in which water moves out, decreasing the heath of the organism immunological response: this happens because of the various pathogens, toxins and allergens that affect the body, this response releases histamine as a way to contradict the pathogens, toxins and allergens, helping the health of an organism get better
Explain why each of the following disorders are the result of a deleterious alteration of feedback mechanisms: diabetes mellitus in response to decreased insulin dehydration in response to decreased antidiuretic hormone Graves' disease blood clotting
diabetes mellitus: body can no longer produce insulin or produces very little insulin dehydration: body has very little to no water in the blood stream Graves disease: overactivity of thyroid gland blood clotting: cannot clot blood
How does the expression of genes for tissue specific proteins result in observable cell differentiation?
different genes code for different proteins and different tissues differentiation basically is just how cells are different for each of their functions
Explain why the following are examples of how organisms use various strategies to regulate body temperature and metabolism: endothermy ectothermy elevated floral temperature
endothermy: organisms regulate their own body temperature and metabolism ectothermy: the environment regulates body temperature and metabolism elevated floral temperature: plants
How is the concept of common ancestry supported by each of the following illustrative examples of homeostatic control mechanisms? execretory systems in flatworms, earthworms and vertebrates osmoregulation in bacteria, fish and plants osmoregulation in aquatic and terrestrial plants circulatory systems in fish, amphibians and mammals thermoregulation in aquatic and terrestrial animals (countercurrent exchange mechanisms)
excretory systems: this supports common ancestry because each of the organisms have excretory systems in order to remove wastes to maintain homeostasis osmoregulation: this supports common ancestry because each of the organisms regulate in order to maintain homeostasis thermoregulation: this supports common ancestry because each of the organisms regulate body temperature to maintain homeostasis
Explain how each of the following illustrative examples provide evidence of the importance of apoptosis in normal development and differentiation: morphogenesis of fingers and toes immune function C.elegans development flower development
fingers and toes: before we had fingers and toes, we had webbed hands and feet. we needed apoptosis to have philanges immune function: helps in the immune response with the natural killing of infected cells flower development: guides the development of the necessary and unnecessary organs in plants
Describe the following mechanisms for obtaining nutrients and eliminating wastes: gas exchange in water and terrestrial plants digestive mechanisms in animals, such as food vacuoles, gastrovascular cavities, one-way digestive systems respiratory systems of aquatic and terrestrial animals nitrogenous waste production and elimination in aquatic and terrestrial animals
gas exchange: Plants obtain the gases they need through their leaves. They require oxygen for respiration and carbon dioxide for photosynthesis. The gases diffuse into the intercellular spaces of the leaf through pores, which are normally on the underside of the leaf digestive mechanisms: nutrients are taken in through leafs, oxygen and cellular respiration are both needed for various functions respiratory systems: oxygen is taken in or removed from the water, carbon dioxide is released as a waste product nitrogenous waste production: wastes are removed during digestion and eliminated through the digestive tracts
How do each of the following illustrative examples provide evidence that disruptions to ecosystems impact the dynamic homeostasis of the ecosystem: invasive and/or eruptive systems human impact hurricanes, floods, earthquakes, volcanoes and fires water limitation salination
invasive species: invasive species take crucial nutrients from native organisms, causing native organisms to stretch resources to try and meet homeostasis human impact: we impact homeostasis by changing the environmental conditions under which each of the organisms have evolved to live under environmental problems: homeostasis is impacted by the changing of environmental conditions under which of the organisms have evolved to live under salination: a change in salinity can drastically alter homeostasis of an individual who can only survive under certain salinities
Provide evidence for each of the following immune responses: invertebrate immune systems have nonspecific response mechanisms, but they lack pathogenspecific defense responses plant defenses against pathogens include molecular recognition systems with systemic responses (compartmentalization) vertebrate immune systems have nonspecific and nonheritable defense mechanisms against pathogens
invertebrate: sea stars will attack initial invaders, but will not protect against pathogens plants: plants can defend against pathogens by recognizing the type of pathogen and initiating a response vertebrate: depending on the pathogen, humans have nonspecific and nonheritable defense mechanisms
What does it mean for a cellular environment to be hyper-, hypo- and isotonic? How does this help determine the water potential of a system?
isotonic: the water potential is pretty much in equilibrium hypertonic: high concentration hypotonic: low concentration water potential will always move from low to high concentration
Explain why each of the following are illustrative examples of positive feedback: lactation in mammals onset of labor in childbirth ripening of fruit
lactation: this is positive feedback because more milk needs to be produced in order to feed children labor: this is positive feedback because labor needs to be increased in order to get the child out ripening of fruit: this is positive feedback because the fruit needs to ripen quickly
Describe the processes carried out by the light dependent reactions, including their reactants and products. What are the products used for? Your answer should include a discussion of the following terms: ADP/ATP, ATP synthase, calvin cycle, carbohydrates, carbon dioxide, chlorophylls, chloroplasts, electrochemical gradient, electron transport chain, electrons, free energy, hydrogen ions, inorganic phosphate, NADPH, photosynthesis, photosystems 1 and 2, proton motive force, stroma, sunlight, and thylakoids)
light is absorbed by pigments of PS II - transferred to chlorophyll p680 e- is transferred to P, e- acceptor of PS II water splits e- passed down ETC to PS I, energy used to pump H+ from stroma to thylakoid space e- passed to p700 chlorophyll a, transfer to e- acceptor of PS - e- passed to NADP+ via second transport chain end result: ATP made by photophosphorylation
Light Reaction
light is absorbed by pigments of PS II - transferred to chlorophyll p680 e- is transferred to P, e- acceptor of PS II water splits e- passed down ETC to PS I, energy used to pump H+ from stroma to thylakoid space e- passed to p700 chlorophyll a, transfer to e- acceptor of PS - e- passed to NADP+ via second transport chain end result: ATP made by photophosphorylation thylakoids, photo part, photosystem I and II converts solar energy to chemical energy water is split into electrons, protons and oxygen chlorophyll/pigment is required photophosphorylation occurs
How would changes to free energy availability result in changes to a population?
lots of free energy can increase the size of a population little free energy can decrease the size of a population
Why are membranes required for active transport to take place? Provide an illustrative example of this.
membranes are required for active transport to take place because the membrane holds the membrane proteins in place so they don't move
Electron Transport Chain
mitochondrial membrane with cristae 32-34 ATP oxidative phosphorylation begins with NADH, FADH2, e, H+ ends with H2O and ATP chemiosmosis ATP synthase - ATP from H+/e occurs in the mitochondrial membrane (cristae) aerobic process, needs oxygen takes the electrons from NADH and FADH2 and passes them through numerous coenzymes and eventually gives them to oxygen (very electronegative) to form water as electrons get passed, they give up energy that runs a series of proton pumps (H+) in mitochondrial inner membrane, pump H+ from matrix into the inner membrane space, as electrons are passed down
Explain why each of the following are illustrative examples of negative feedback" operons in gene regulation temperature regulation in animals plant responses to water limitations
operons: they can limit the stimulus in order to get the organism back to homeostasis temperature regulation: organisms will increase or decrease temperature to face various environmental effects, but then the body will return to homeostasis once the environmental issue is fixed plant responses: plants will shrivel up in response to water limitations but once water becomes available, the plant will take in enough to return to homeostasis
How are the following example responses to information and communication? How can each be correlated to natural selection? photoperiodism animal behavior (hibernation, estivation, migration, courtship)
photoperiodism: this is a response to the changes in the sunlight availabilities, those who get the most sunlight will be naturally selected for animal behavior: these are responses to environmental stimuli, those who have the best responses are naturally selected for
Describe how each of the following are examples of autotrophs capturing free energy from physical/inorganic sources in the environment: photosynthetic organisms chemosynthetic organisms (in the absence of oxygen)
photosynthetic organisms: Photosynthetic organisms capture free energy present in sunlight. chemosynthetic organisms: Chemosynthetic organisms capture free energy from small inorganic molecules present in their environment, and this process can occur in the absence of oxygen.
how do the following plant physiological events involve interactions between internal/external signals and environmental stimuli and internal molecular signals: phototrophism photoperiodism
phototrophism: as a result of environmental stimuli, plants have the tendency to lean or reach towards light photoperiodism: as a result of environmental stimuli, plants change their cycle in response to the changing in day lengths
Summarize the steps involved with the nitrogen cycle. Be sure to include the organisms needed to perform each step, as well as the molecules made at each step.
please see picture
Summarize the steps involved with the carbon cycle. Be sure to include the molecules being made at each step.
please see picture attached
Describe the concept of positive feedback in terms of response amplification and the introduction of a stimulus. How does this differ from negative feedback in terms of the set point?
positive feedback amplifies the stimulus negative feedback inhibits the stimulus in order for the organism to return to an equalized state
Glycolysis
requires 2 molecules of ATP or usable energy splits a 6 carbon glucose into 2 molecules of pyruvic acid with 3 carbons - takes three paths Path 1: alcohol fermentation by bacteria and yeast, produces CO2, ethanol and 2 NAD+, yields 2 ATP Path 2: lactic acid fermentation by muscle cells, produces lactate and NAD+, yields 2 ATP Path 3: forms pyruvic acid, combines with CoA enzyme, forms acetyl CoA, enters the mitochondria for the Krebs cycle and electron transport chain
Explain how each of the following illustrative examples are solutions to the surface area to volume ratio problem: root hairs, cells of the alveoli, cells of the villi, microvilli
root hairs: have high surface area to volume ratio in order to draw in lots of moisture and nutrients from the soil alveoli: have high surface area to volume ratio in order to exchange gases in the lungs faster villi/microvilli: have high surface area ratios to aid in various body functions
Explain how the following reproductive strategies are ways to adjust to varying energy availability: seasonal reproduction in animals and plants life history strategy (biennal plants, reproductive diapause)
seasonal reproduction: various plants have evolved to have seasonal reproduction in order to get the most energy available in order to reproduce properly biennal plants: this adjusts to varying energy available because these types of plants take two years to fully reproduce, so the energy intake is done over a longer period of time reproductive diapause: as organisms get older, their reproductive organs stop working as best as they should because the majority of the energy available goes to the younger organisms
Describe the concept of selective permeability, as describe by the fluid mosaic model of the cell membrane.
selective permeability refers to the selective process of what is allowed to pass through the cell membrane easily the fluid mosaic model explains this because there are many elements in the cell membrane that allow various materials to pass through easily
Compare and contrast simple diffusion vs facilitated diffusion, providing illustrative examples of each
simple diffusion is simply the passing through of small and polar materials facilitated diffusion uses various pumps in order to transfer things across the cell membrane
How does each of the following illustrative examples affect the activity of organisms? Provide whether each of these biotic or abiotic: symbiosis predator-prey relationships water and nutrient availability, temperature, salinity, pH
symbiosis: it depends on the type of symbiosis that occurs, if the relationship is positive the activity of organisms increases, but if not, it can really decrease, biotic predator-prey relationships: this also depends on the relationship, biotic water and nutrient availability: the more available, the more active organisms are, abiotic temperature: depends on the organism, abiotic salinity: depends on the organism, abiotic pH: depends on the organism, abiotic
describe the relationship between metabolic rate per unit body mass and the size of multicellular organisms
the higher the metabolic rate per unit of body mass, the smaller the size of the multicellular organism
How does the polarity of a protein's side groups help it remain embedded in the cell membrane?
the polarity of a protein's side groups can help it remain embedded in the cell membrane by getting through to a certain extent before the polarity changes and the protein can no longer get through successfully
How must free energy needs be adjusted during times of reproduction and child rearing?
there must be an increase in free energy intake during reproduction and child rearing because reproduction and rearing of offspring require more free energy than is used for maintenance and growth.
Describe how each of the following examples allow living systems to maintain dynamic homeostasis without violating the second law of thermodynamics: coupling -delta G processes with + delta G processes energy input is greater than free energy lost coupling exergonic reactions with endergonic reactions
these examples are all basically the same thing but with different word choice. They maintain homeostasis without violating the second law of thermodynamics by coupling processes. This means that exergonic (spontaneous reactions) are used to drive endergonic (nonspontaneous reactions) ones
Describe how each of the following examples are sequential, energy related pathways in biological systems and may be entered at multiple points in the pathway: krebs cycle glycolysis calvin cycle fermentation
these examples are sequential because they occur in order. In cellular respiration, it begins with glycolysis and fermentation, and goes onto the formation of CoA, Krebs and electron transport chain. In photosynthesis, it begins with the light dependent reaction of the ETC and then goes to the light independent reaction of the Calvin cycle. By the multiple points of the pathway section, this means that multiple molecules can enter the pathway at multiple points in the pathway.
