Answer:
Explained
Explanation:
Let me first make the opposite clear: there is a necessity in the item. For example, it is essential to try to turn an acorn into an oak. At that point the importance of snuffing it is in the downpour that suffocates it, or the heat that heats it, or the squirrel that is consuming it.
It's regarded as the "last" trigger that the acorn will do, as it can't resolutely try. Different causes are known as the "proficient" cause: "Evaporating it was the efficacy of the sun on the acorn," unlike what the sun would do to a heap of residue. It's dry right now, so the sun would just warm it up.
Hume agreed that we could confirm that, on the grounds that the movement of billiard balls on each other gives the mind the requirement of believing one ball pushes the other— bearing in mind that we have seen that we believe this impact— that since it occurs while we see it, we expect it and conclude that it will repeatedly do something very close.
In any case, he claims we trust it just because that's the way our psyches work, not because we can "demonstrate" any further that a billard ball hitting another is going to move it, but because our brains only act to make us accept we can really decide the cause.
Final answer:
David Hume's statement reflects his view that causality and moral necessity reside in our perceptions and sentiments, not in objects or facts. By emphasizing experience and subjective emotion, Hume presented a philosophy where 'ought' cannot be derived from 'is', and causality is inferred, not intrinsic.
Explanation:
The statement "Necessity is something in the mind, not in the objects" refers to David Hume's understanding of causation and moral judgments. Hume challenged the conventional thinking of his time by asserting that what we consider necessary, like the cause of an effect, does not exist inherently in objects but is a construction of the human mind based on experience and the constant conjunction of events. Morality, in Hume's view, stems from human sentiments and cannot be deduced from facts alone; it is not a matter of objective fact but of subjective feeling.
Hume argued that while we may perceive certain events as constantly conjoined, it is a product of habituation rather than an intrinsic truth of the objects themselves. This line of reasoning led Hume to posit that we cannot derive an 'ought' from an 'is' – suggesting that moral principles cannot be concluded directly from observations of nature. Furthermore, Hume questioned whether there can be a necessary being at all since we can conceive of any being's nonexistence without contradiction.
In essence, Hume believed that causality is not a priori knowledge but an inference from our experiences. As for morality, it is based on sentiment and subjective perceptions rather than objective reality, implying that our sense of duty and moral judgments are not embedded in objects or facts, but in our emotional responses to them.
When mosquitoes are very abundant, purple martins flock to the area and specialize on them. When mosquito populations are not large, purple martins are similarly scarce and feed on other insects. This is an example of
A) community carrying capacity.
B) ecosystem carrying capacity.
C) exotic regulation.
D) density-independent regulation.
E) density-dependent regulation
Answer:
The correct answer is E) density-dependent regulation.
Explanation:
When the population growth rate is dependent on the density of a population then it comes under density-dependent regulation. Usually, when a population becomes denser the mortality rate becomes high in that population.
This regulation can occur due to factors like predation, disease, inter or intraspecies competition. So here when the density of the mosquitoes becomes high then purple martin flock to the area and specialize in them to gain nutrition which stabilizes the population of mosquitoes again.
Density-dependent regulation is more significant when the population density of a species increase. So the right answer is E.
Marfan's syndrome is the result of inheriting a single allele. Individuals with Marfan's syndrome are tall and long-limbed, and have both cardiovascular and eye defects. The inheritance of Marfan's syndrome is an example of?
Answer:
Pleiotropy
Explanation:
Marfan syndrome is an example of pleiotropy, which can be defined as the phenomenon in which a pair of allele genes conditions the appearance of several traits in the same organism.
All of these traits occur through the action of only one pair of genes, so pleiotropy shows that the idea that each gene affects only one trait is not always valid.
In other words, a pleiotropic gene can have an effect on several phenotypes at the same time, due to the fact that the mutated gene is used by a group of cells (or targets) that have the same signaling function.
During a routine physical examination on an older female client, a nurse notes that the client is 5 feet, 3/8 inches (1.6 m) tall. The client states, "How is that possible? I was always 5 feet and 1/2? (1.7 m) tall." Which statement is the best response by the nurse?
a) "The posture begins to stoop after middle age."b) "After menopause, the body's bone density declines, resulting in a gradual loss of height."c) "After age 40, height may show a gradual decrease as a result of spinal compression"d) "There may be some slight discrepancy between the measuring tools used."
Answer:
B
Explanation:
The nurse should tell the client that after menopause, the loss of estrogen leads to a loss in bone density, resulting in a loss of height.
You are confronted with a box of preserved grasshoppers of various species that are new to science and have
not been described. Your assignment is to separate them into species. There is no accompanying information as
to where or when they were collected. Which species concept will you have to use?
A) biological
B) phylogenetic
C) ecological
D) morphological
Answer:
The correct answer will be option-D
Explanation:
The morphological species concept is the concept which defines the species based on the morphological characters.
The species which can be grouped or organised on the basis of the morphological traits including the anatomy of the organisms arr called morphospecies and the concept is known as a morphological concept.
In the given question, since there is no information available for the collected grasshoppers, therefore, the biologist will classify the grasshopper species by studying the morphological characters of the species.
Thus, option-D is the correct answer.
How are parasitic fungi different from other fungal symbionts?
Answer:
Explanation:
In contrast to other fungi symbionts for example: saprotrophic fungi, parasitic fungi attack living organisms, they invade them, penetrate their outer defense mechanism and take nourishment from the cytoplasm of living things and cause disease which may result to death of the host. Most disease causing or pathogenic fungi are parasitic to plants.
The eggs and larvae of marine animals tend to require water with more dissolved oxygen in it than the adults do. If water flows from a freshwater source into a salt water bay, what effect would this have on the population of marine animals?
Answer:The population will drop.
Explanation:
This is because the fresh water of high water potential will lower the solute potential of the salt water when they mixed up; to create a HYPOTONIC ENVIRONMENT for the larvae and the eggs.
Therefore, the higher water potential drives in water into the larva and egg membrane, down the water gradient by OSMOSIS. This made the cells and its organells to swell up until the elastic limit of the cell membrane is exceeded.
The products busted (eggs and larvae) once the elastic limit / stretching limit is exceeded leading to death of larvae and destrction of the egg, with eventual drop in population of the marine animals; since reproduction has been truncated( old animals are not replaced with young ones from the eggs and larvae.)
The powerful survival impulse that leads infants to seek closeness to their caregivers is called
Answer: Attachment
Explanation: Infants tend to be attached to their parents. For good reason because the parents usually treat kids very well during infancy, and its the only thing the infants understand or know.
Two terms for the massive motor tracts serving voluntary movement are ________. Two terms for the massive motor tracts serving voluntary movement are ________. pyramidal and corticospinal extrapyramidal and rubrospinal supplementary and cerebellar-pontine segmental and nigrostriatal
Answer:
pyramidal and corticospinal
Explanation:
Motor pathways control body posture, reflexes and muscle tone, as well as conscious conscious movements. The best known motor route is the pira pyramid system ', which begins in the large pyramidal neurons of the motor cortex, continues along the pyramids of the brain stem and ends at or near the alpha motor neurons. This motor system is extraordinarily important in the clinic, because it is frequently affected by vascular accidents of the brain.
During recess, children are trying to balance a seesaw. If one side is too low, a heavier child will get off and be replaced by a lighter child; if one side is too high, a lighter child will be replaced by a heavier one. The children’s behavior is similar to our biological states as they try to create:______
Answer:
Homeostasis
Explanation:
Homeostasis is a process in the body where it tries to find a state of dysmic equilibrium
Answer:
Equilibrium.
Explanation:
Our body seeks to keep its internal functions in balance, even with variations in the environment in which it finds itself. This balance is called homeostasis and can be observed when our body tries to adapt to cold, hot days, reduced food and water, physical effort, among others.
An example of this can be seen in the question above, where an individual seeks to keep the two sides of a seesaw in balance.
Indicate if the conditions described would result in the development of a male or a female individual. SRY is a gene on the Y chromosome that is involved in initiating the development of the male phenotype in humans.
Final answer:
The presence and functionality of the SRY gene on the Y chromosome dictates the development of a male phenotype, leading to testis formation and testosterone secretion. Without a functional SRY gene, the embryo will develop female sex characteristics by default.
Explanation:
The conditions described would result in the development of a male individual if the SRY gene is present and functional. The SRY gene of the Y chromosome in embryonic germ cells produces the testis-determining SRY protein. This sets off a cascade of genetic activations that lead to the differentiation of the bipotential gonadal tissue into testes, which then secrete testosterone to further the development of male sex characteristics. Conversely, if the SRY gene is not present (as is the case for females with XX chromosomes) or it is mutated (as in conditions like Swyer syndrome), the individual will develop female characteristics.
A typical XY genotype with a functional SRY gene will inevitably cause an embryo to develop into a male. However, without the SRY gene or if a mutation occurs within it, the default development of the embryo will be a female. Cellular differentiation within the bipotential gonads will occur towards the formation of oogonia and primordial follicles in the ovary, rather than forming spermatogonia as it would in the presence of SRY.
Which structure is indicated by letter D?
O Posterior dorsal root
O Anterior ventral root
O Peripheral nerve
O Dorsal horn
The structure indicated by letter D is the Dorsal horn.
Explanation:The structure indicated by letter D is the Dorsal horn. The dorsal horn is a region of gray matter within the spinal cord that receives sensory information from the body via the posterior dorsal root. It is involved in processing and transmitting sensory signals to the brain.
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A student travels to Brazil by boat on the Amazon River, without visiting the doctor prior to traveling for recommended vaccinations for travel to South America. The student becomes ill during the trip and is quarantined. Which of the diseases listed below does the student most likely have?
A) hantavirus
B) yellow fever
C) Ebola
D) Q fever
Answer:
The correct answer is B) Yellow fever
Explanation:
Yellow fever is a viral disease and this disease is spread by the bite of female Aedes aegypti mosquitoes that are found in Brazil and many other South American countries and the chances of getting yellow fever gets increase when anyone travels through amazon river.
The symptoms of yellow fever disease are fever, headache, back pain, nausea, and in some people it causes liver damage which results in yellowing of the skin.
So if anyone is traveling to Brazil in South America then he must be vaccinated for yellow fever which is also recommended by the WHO and CDC. Therefore yellow fever would be the disease that the student would most likely to have.
Final answer:
The student most likely has yellow fever, which is caused by the yellow fever virus transmitted by mosquito vectors.
Explanation:
The student most likely has yellow fever.
Yellow fever is caused by the yellow fever virus and is transmitted to humans by mosquito vectors. It occurs primarily in tropical and subtropical areas in South America and Africa. The virus can be transmitted from infected monkeys to humans in tropical jungle regions, or between humans in urban areas.
Prevention of yellow fever includes the use of mosquito netting, window screens, insect repellents, insecticides, and vaccination for those traveling to endemic areas.
What is the traditional name of the group of fungi that lack sexual reproduction?
Answer:
Deuteromycota fungi.
Explanation:
Deuteromycota which is known as imperfect fungi. It is a polyphyletic group of fungi, and they are not reproducing through the process of sexual reproduction. Most member of this phylum are leaves on land and few aquatic member are exceptions.
Reproduction in Deuteromycota are asexual means these fungi produce their spores with the help of asexual reproduction and this process is known as sporogenesis. Some example of this phylum are:
1) Penicillium camemberti.
2) Aspergillus oryzae.
3) Lecanicillium sp.
Ion channel gates close the pores of some ion channels in response to
Select one:
a. a change in electrical charge.
b. stretching of the cell membrane.
c. the binding of specific molecules to the channel.
d. All of the above
Answer:
All of the above
Explanation:
The ions present in our body can move through voltage gated ions channels present in the cell. The ions are unequally distributed in the interior and exterior of the cell.
The ion gated channel may get open or close depending upon the presence of the different ions. These ions movement changes the electric potential of the cell. The ions movement results in the propagation of the nerve impulse and may cause the cell membrane stretching. The binding of the molecules to the ion channels may open or close the movement of particular ions.
Thus, the correct answer is option (d).
Final answer:
Ion channel gates can close in response to changes in electrical charge, mechanical stretching of the cell membrane, or the binding of specific molecules, meaning 'All of the above' is the correct answer.
Explanation:
Ion channel gates are integral components of cellular membranes and respond to various stimuli to maintain the cell's homeostasis. The closing of the pores of ion channels can occur due to a change in electrical charge, resulting from a change in membrane potential; mechanical stretching of the cell membrane, which can be detected by mechanically gated channels; or the binding of specific molecules to the channel, such as ligand-gated ion channels responding to neurotransmitters, or the interaction with G-proteins that may indirectly lead to channel opening.
Therefore, when we consider the stimuli that can lead to the closing of ion channel gates, the correct answer to the question is d. All of the above. Ion channels allow rapid and selective ion transport across cellular membranes, contributing to crucial processes such as the transmission of nerve impulses and muscle contraction.
You have an F2 generation derived from two true-breeding parents (AA and aa) with different characteristics for the same trait (determined by a single gene). What percentage of the recessive phenotype would you expect to be true breeding if they were self-fertilized?a. 0%.b. 33%.c. 67%.d. 25%.e. 100%
Answer:
The answer is letter B.
Explanation:
The percentage of the recessive phenotype would be 33%.
Non-disjunction involving the X-chromosome may occur during oogenesis and produce two kinds of eggs. If normal sperm fertilize these two types, which of the following pairs of genotypes are possible?
a. XX and XY
b. XXY and XO
c. XYY and XO
d. XYY and YO
Answer:
The correct answer will be option-B
Explanation:
Non-disjunction is the process of the failure of the separation of the homologous chromosomes during cell division which could be observed during the meiosis I, meiosis II or mitosis.
If Non-disjunction takes place during the oogenesis then the resultant cells will be formed with XX and O gametes.
When a normal male sperm with XY fertilizes the cells then they will form four combinations:
1. XX + X = XXX
2. XX + Y = XXY
3. O + X = XO
4. O + Y = YO
Thus, in the given question option-B is the correct answer.
Non-disjunction involving the X-chromosome during oogenesis can produce two types of eggs: XX and O. When these are fertilized by normal sperm, the viable genotypes that can result are XXY and XO. YO is not a viable genotype and will not develop.
Explanation:The term non-disjunction in biology refers to the failure of chromosome pairs to separate properly during cell division, which can result in aneuploidy. Aneuploidy is a condition in which a cell has an abnormal number of chromosomes. Specifically in the context of this question, non-disjunction involving the X-chromosome during oogenesis (egg production) can produce two types of eggs: one with two X chromosomes (XX) and one without an X chromosome (O). When normal sperm (either X or Y) fertilize these two types of eggs, four combinations are possible: XX, XY, XO, or YO.
The viable combinations, however, are XX and XO. This is because an embryo with the genotype YO (having only a Y chromosome and no X chromosome) is not viable and won't develop. Thus, the correct answer is option 'b. XXY and XO'.
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Organisms that use energy from sunlight or inorganic substances to make organic compounds
Answer:
Autotrouph
Explanation:
The image shows part of the humerous bone in different genera of primates.
Which statement is best supported by the observable structures of the different humerus bones?
A)
The primates lived in similar environments.
B)
The primates shared a common ancestor.
C)
The primates interbreed with similar organisms in a population.
D)
The primates had diets that consisted of similar types of foods.
Answer:
B) The primates shared a common ancestry.
Explanation:
I took a test EXACTLY like this a very long time ago, and since they look similar all the way down, passed down from generation to generation, this would be the obvious answer.
I am joyous to assist you anytime.
The primates shared a common ancestry.
What is Humerus Bone?The humerus is a long bone that extends from the shoulder and scapula (shoulder blade) to the elbow.
It is sometimes referred to as the upper arm bone. Proximal humerus fractures and humerus shaft fractures are the two categories used to classify humerus fractures.
A proximal humerus fracture can occur at different levels and with either a simple or comminuted fracture pattern. It typically happens close to the shoulder joint. On the other hand, a fracture of the humerus shaft is limited to the middle of the upper arm.
Therefore, The primates shared a common ancestry.
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The primary motor cortex for control of voluntary muscles is found in the
Answer: The primary motor cortex for control of voluntary muscles is found in the precentral gyrus of the frontal lobes.
Explanations:
The primary motor cortex is one of the important brain areas involved in motor function. It is found in the precentral gyrus of frontal lobes. It control voluntary muscles and generate impulses needed for movement execution.
Voluntary muscles are muscles that we can control consciously or we can control them at will and we can choose when we want to use them. They are also refers to as skeletal muscles and are attached to bones. The are majorly use for locomotion.
Answer:
I'm terrible at explaining so here's a screenshot
- Ripper
Explanation:
Explain why predators and prey with many generations of interactions are likely to have pronounced behavioral responses to each other.
Answer:
Due to coevolution
Explanation:
Coevolution occurs when the evolution of two species (or more) is influenced by the biological relationships between those species. It is, the evolution takes place in a mutually dependent manner. A type of coevolution, is that of the type Predator-Prey , in which a selective pressure on the prey generates new features to avoid being captured, but at the same time, the predator evolves to overcome the new features adopted by the prey becoming a more effective hunter. Thus, coevolution often leads to an evolutionary arms race between prey and predator
The predator-prey relationship involves coevolution, where both species influence each other's evolution over many generations. This leads to pronounced behavioral responses and adaptations in both predator and prey, based on survival strategies such as enhanced hunting and evasion tactics. Cyclic population fluctuations are common in these relationships.
Explanation:Predators and prey with many generations of interactions are likely to have pronounced behavioral responses to each other due to coevolution. This process involves two species influencing each other's evolution over time.
An example of this is the lynx and snowshoe hare. Over generations, the lynx has evolved to become an efficient hunter of the hare while the hare has evolved in its ability to evade the lynx. The predator-prey relationship leads to a cyclical pattern where the rise and fall of predator and prey populations are interconnected. When the hare population increases, it provides more food for the lynx, which increases the lynx population. However, when the lynx population becomes too dense, it leads to a decrease in the hare population due to over-predation and in turn, the lynx population also decreases due to scarcity of food. Similar interactions result in a strong behavioral response and adaptations in both predator and prey, such as enhanced hunting skills in the predator and evasion tactics in the prey. In addition, both species undergo some form of defense mechanism evolution to reduce the impact of predation.
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________, which is released from the pituitary gland, can potentially increase the height and weight of an individual to gigantic proportions, especially if administered during childhood and adolescence.
Answer:
Growth hormone
Explanation:
The growth hormone is released by somatotropic cells of the anterior pituitary gland. The growth hormone is an anabolic hormone and metabolic, tissue building and growth-promoting effects on the body. It stimulates the mobilization of fats, increases the blood levels of fatty acids to be used as flues for ATP production. It reduces glucose uptake and triggers glycogen breakdown.
In response to growth hormone, insulin-like growth factors are produced by the liver, skeletal muscle, bone, and other tissues which in turn facilitate growth by cell division, stimulated formation of collagen and deposition of bone matrix.
The growth hormone triggers cell division and cell enlargement, stimulates the growth of long bones by affecting the epiphyseal plate. It also stimulates the skeletal muscles to increase muscle mass. The overall effect is somatic growth. Its hypersecretion during childhood and adolescence can cause gigantism since the active epiphyseal plates promote excess bone growth.
A match between the DNA in a sample and the genomic DNA of a particular individual for a single tandem repeat site is not sufficient to establish identity. However, a mismatch is definitive. The primary reason is that:
Answer:
The mismatch is definitive, the primary reason is that, the DNA in the sample must match the original genomic DNA.
Explanation:
Tandem repeat takes place only when 'one or more nucleotide pattern is repeated' and it is 'adjacent' to each other. Mismatch indicates that the sample DNA is not the source for that Original DNA. If the sample is the actual source of the original genomic DNA, then it must be matched exactly.The DNA is matched with the sample DNA in the process of DNA fingerprinting. The mismatch of DNA is representative that the DNA sample does not belong to the original DNA.
What is DNA fingerprinting?DNA fingerprinting is the process of matching the DNA sample with the original DNA based on the tandem repeats.
The tandem repeat is the repeated unit of the nucleotides in the genetic material. When the sample DNA did not match the original DNA strands, it is the representation of mismatch.
The mismatch in the DNA sequence describes the absence of relation between the original and sample DNA.
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In humans, a recessive allele of a gene on the X chromosome causes humans to be "colorblind." A colorblind XY man and an XX woman whose genotype is homozygous for normal color vision have children together. What percentage of their offspring are expected be colorblind?
Answer:
The answer is 0%.
Explanation:
If X⁻ represent the recessive allele that causes colorblind, and X⁺ represents the dominant allele, thus:
X⁻Y is the genotype of the colorblind man (he is carrier and he has the disease)
X⁺X⁺ is the genotype of the woman (she has normal vision and is not carrier)
When they have children together, the offspring will have the following genotypes:
X⁻Y x X⁺X⁺ = X⁻X⁺ ; X⁻X⁺ ; X⁺Y ; X⁺Y
Summarizing, they will be 50% X⁻X⁺ (women with normal vision, carrier) and 50% X⁺Y (men with normal vision, non carrier).
No child will have the disease because its expresses when the genotype is homozygous for colorblind allele (X⁻X⁻).
Current genetic research has found that bipolar disorder has a strong and complex genetic component. Perhaps one reason that the genetic component of bipolar disorder is so strong is that______.
People are more likely to develop bipolar disorder if they have a close relative with the condition.
Answer:
The answer it Is probably linked to more than one gene
Explanation:
The human colon supports a large population of beneficial bacteria. How are these bacteria beneficial?
Carbonydrate loading a. provides a competitive edge for award-winning sprinters, bodybuilders, and weight lifters b. involves manipulating dietary patterns and physical activities prior to an endurance event c. often results in short-term weight loss and positive energy balance d. is generally recommended for long-term weight control for athletes
Answer: Option B.
Carbohydrate loading involves manipulating dietary patterns and physical activities prior to an endurance event.
Explanation:
Carbohydrate loading is a method used by endurance athletes to increase their glycogen (energy level) storage in the muscles and livers by changing their diets and physical exercises. This is done a week before an endurance activity and it is my increasing the intake of Carbohydrates by 8 to 12 kilogram by weight of the body. This give you more energy to compete for physical activity with less fatigue for a long period of time as we know that physical activity requires energy.
It became apparent to Watson and Crick after completion of their model that the DNA molecule could carry a vast amount of hereditary information in which of the following? Group of answer choices sequence of bases side groups of nitrogenous bases complementary pairing of bases phosphate—sugar backbones different five-carbon sugars
Final answer:
The DNA molecule carries a vast amount of hereditary information in the sequence of bases, which enables precise replication and transmission of genetic information, essential for protein synthesis and cell function.
Explanation:
The Role of DNA Base Sequence in Hereditary Information
It became apparent to Watson and Crick after completion of their model that the DNA molecule could carry a vast amount of hereditary information in the sequence of bases. Each DNA molecule consists of two strands forming a double helix, with the backbone made of phosphate and sugar groups, and nitrogenous bases inside. The base pairing is specific—adenine (A) always pairs with thymine (T), and guanine (G) pairs with cytosine (C). This complementary nature not only stabilizes the DNA structure but also allows for the precise replication of genetic information during cell division.
The information for building proteins is encoded in the sequence of these bases, often read in groups of three, known as codons, each specifying an amino acid in a protein. Thus, the sequence of bases along the length of a DNA molecule is fundamental in storing and transmitting hereditary information. This principle underlies all genetic functions, from the replication of DNA to the synthesis of proteins crucial for cellular function.
Most Swiss starlings produce four to five eggs in each clutch. Those producing fewer or more than this have reduced fitness. Which of the following terms best describes this?
a. directional selection
b. stabilizing selection
c. disruptive selection
d. sexual selection
e. artificial selection
Iodine is a yellowish solution. A starch solution is white. A starch solution turns purplish-black in the presence of iodine. If you wait a few hours, then add iodine to the beaker, what color would the beaker solution be?
Answer:
The correct answer will be- the color change will be observed and the solution will turn purplish-black.
Explanation:
Iodine test is performed to test the presence of the carbohydrates mainly starch.
The iodine solution is chemically called potassium iodide which forms a yellow solution. The potassium iodide solution forms a complex with a starch solution which appears a purplish-black color which shows the presence of the carbohydrates.
In the given question, if we add the iodine solution to the beaker after a certain point of time then it will still form a complex with the starch and thus beaker solution will appear darker in color.
During photophosphorylation in plants, electrons flow through a series of carriers in the chloroplast. What is the ultimate donor of electrons, and what is the ultimate acceptor? What provides the energy to move those electrons?
The ultimate donor is H2O, and the acceptor, NADP+. The energy that drives this electron flow is from light.