Answer:
C
Explanation:
I took the test
What do scientists think were the first eukaryotic organisms on Earth?
euglena
paramecium
plasmodium
amoeba
According to the given information euglena were the first eukaryotic organisms on Earth.
What organism is eukaryotic?Eukaryotes are organisms whose cells have membrane-bound organelles in addition to a nucleus. Eukaryotic organisms come in a wide variety, along with most algae, all mammals, vegetation, fungus, and protists. Eukaryotes can have a single cell or many cells. They are referred to as the "powerhouse of the cell" because they generate energy (ATP). helps to control the metabolism of cells.
What five eukaryotic organisms are examples?Humans, fungi, protists, and plants are eukaryotes cell examples. They have chromosomes, which organize the genetic material. Eukaryotic have the Golgi, mitochondrial, golgi apparatus, and nucleus. Let's look more closely at the elements of eukaryotic cells.
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which of these lines of evidence would not be used by a biologist to determine the relationship between two organisms?
Answer:put in the comments the options.
Explanation:
Consider the cell cycle shown below. A cell will stop dividing and go into Go, the resting phase, if it
receives the proper signal at the G₁ checkpoint.
The locations for three genes have been added to this cartoon. For clarity, the locations have only been noted on one chromatid. The lowest frequency of crossovers would occur between genes ____ and ____.
The lowest frequency of crossovers would occur between genes a and b (the genes closet to one another on a chromosome)
The exchange of genetic material between the non-sister chromatids of two homologous chromosomes during sexual reproduction, or chromosomal crossover, leads to recombinant chromosomes. It is one of the last stages of genetic recombination, which takes place during the synapsis process at the pachytene stage of prophase I of meiosis. Before the synaptonemal complex forms, synapsis starts, and it doesn't stop until close to prophase I's conclusion.
The distance between genes is directly inversely correlated with the probability of gene crossing over between two genes that are located on the same chromosome (linked gene). Unlinked genes are assorted independently during cell division when two genes are not found on the same chromosome. Therefore, crossing over occurs frequently.
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Smooth muscle forms rings called ___________ that are usually contracted but relax periodically to allow substances to pass through them.
Smooth muscle forms ring called sphincters that are usually contracted but relax periodically to allow substances to pass through them.
A sphincter is a circular muscle that normally constricts a body channel or opening and opens when required for normal physiological function. There are sphincters in many species.
The human body contains more than 60 different varieties, some of which are minuscule in size, including the numerous precapillary sphincters. At death, sphincters loosen, frequently leaking fluids and feces.
Every sphincter has a connection to the lumen (opening) that it is enclosing. The lumen is narrowed and the sphincter muscle's length is reduced while it is contracted (closed). The muscle lengthens as a result of relaxation, allowing liquids, solids, or gases to pass through.
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When there is a cut in the skin and bacteria enter the body, the immune system responds. First, macrophages approach the area of the cut. Next, the macrophages surround any bacterial cells and engulf them. What feature of the immune system is best described by this scenario?
A.
self-recognition, which is a part of adaptive immunity
B.
the phagocytotic barrier, which is a part of innate immunity
C.
antigen specificity, which is a part of adaptive immunity
D.
the inflammatory barrier, which is a part of innate immunity
The feature of the immune system which is best described by this scenario which involves engulfing of bacterial cells is the phagocytotic barrier, which is a part of innate immunity and is denoted as option B.
What is Immune system?This is part of the body which is responsible for protection and helps to fight germs and diseases through the white blood cells which are present in the body system.
The immune system comprises of macrophages which engulfs the pathogen through the process known as phagocytosis which is why phagocytotic barrier which is a part of innate immunity was chosen as the correct choice.
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during photophosphorylation, the ph of the thylakoid interior will be a) higher than the ph of stroma since protons move into thylakoid b) lower than the ph of stroma since protons move into thylakoid space. c) same as the the ph of stroma since protons go in and out of thylakoid space
Lower than the ph of stroma since protons move into thylakoid space
What is photophosphorylation ?By activating PSII with the help of solar energy, photophosphorylation transforms ADP into ATP. This involves a procedure known as photolysis, which involves splitting the water molecule into oxygen and hydrogen protons (H+). After then, water and PSI are continuously connected by a single-direction flow of electrons.
Actively moving protons from the stroma to the thylakoid lumen requires energy from an electron transport chain. Consequently, the lumen has a lower pH than the stroma and a substantially larger proton concentration.Using light energy from photosynthesis, ADP is converted to ATP through the process of photophosphorylation. It involves adding a phosphate group to an ADP molecule in the presence of light in order to create energy-dense ATP molecules.Learn more about Photophosphorylation here:
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What trait separates the ray finned fish and amphibians
The traits that separate ray-finned fish and amphibians is: swim-bladder, bony scales and lungs.
Swim-bladder is a large sac-like organ present only in ray-finned fish (bony fishes in general). It is a buoyant structure that enables the fish to swim across water. No such bladder is present in the body of amphibians.
Apart from swim-bladder, the fish also consists of bony scales that act as a protective organ upon the surface of fishes. However the outer surface of the skin of amphibians is slimy in texture. Also the fishes breathe only through gills, whereas the amphibians may have gills, lungs or even skin for respiration.
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The principle of ________ states that organisms succeed one another in a definite, determinable order that can be used to recognize a specific time period.
Answer:
Fossil Succession
Explanation:
Which of the following are true in PROKARYOTIC cells?
have ribosomes
small and simple
first cells, prefix meaning "before," thought to be early cells
have a cell membrane
large and complex
have DNA
have organelles and nucleus
no nucleus or membrane bound organelles
Answer:
prokaryotic cells don't have nucleus or membrane bound organelles
in which way(s) are dendrites and axons similar? a both are characterized by branching. b they have similar lengths. c both exhibit a tapering of diameter with increasing distance from the cell body. d all of the above
Dendrites and Axon both have branching as a defining feature.
What are axons and what do they do?Your brain's neurons each have a solitary, lengthy cable that extends from the cell's center. A neuron's axon, a cable that is far thinner than a human hair, is where electrical impulses escape the cell to be picked up by nearby neurons.
Explain dendrites.Extensions called dendrites are designed to pick up messages from neighboring cells. When activated by other neurons, they take the shape of projections with a tree-like structure that transport the electrochemical charge to the cell body (or, more rarely, directly to the axons).
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which objects on earth absorb photons, what is it reflected as?
In the photoelectric effect process, photon loses its entire energy to an atomic electron which is in turn released from the atom.
When a photon is absorbed by an electron it itself get destroyed, but it's energy is transferred into the atoms of the object it hit. That energy may re-emitted as a another photon and it happens when light reflects off an object.
Materials like Coal, black paint, and carbon nanotube arrays absorbs light and materials, such as glass , have no absorbing properties and therefore they look transparent. Photon enters the eye get absorbed by one of the rod or cone cells that envelop the retina on the inner back surface of the eye.
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The ability to detect whether your body is in a horizontal or vertical position depends most directly on.
Answer: the vestibular sense
Explanation:
The ability to detect whether your body is in a horizontal or vertical position depends most directly on (accommodation, sensory adaptation, the vestibular sense, olfactory receptors, subliminal stimulation) While playing tennis, you need to know where your limbs are located so you can move them into right positions or swing your racket.
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During photosynthesis in a eukaryotic cell, an electrochemical gradient is formed across the ___________.
During photosynthesis in a eukaryotic cell, an electrochemical gradient is formed across the Thylakoid space.
What is Thylakoid space ?
The thylakoid space is the area inside the thylakoid. A thylakoid is a membrane-bound disc found in plant chloroplasts. The thylakoid membrane contains enzymes required for photosynthesis's light-dependent reactions. During photosynthesis, an electrochemical gradient or proton motive force is created by the release (photolysis) or movement of protons from the stroma into the thylakoid lumen. The energy released during this movement is used by ATP synthase, CF o, and CF1 particles to form ATP mole.
Inside chloroplasts and cyanobacteria, thylakoids are membrane-bound compartments. They are the site of photosynthesis's light-dependent reactions. Thylakoids are made up of a thylakoid membrane that surrounds a thylakoid lumen. Chloroplast thylakoids frequently form grana, which are stacks of discs. Grana are linked together by intergranal/stromal thylakoids, which connect granum stacks as a single functional compartment. Chlorophyll pigments are found in packets called quantasomes in thylakoid membranes. Each quantasome has between 230 and 250 chlorophyll molecules.
The thylakoid membrane is the site of photosynthesis's light-dependent reactions, with photosynthetic pigments embedded directly in the membrane. It is an alternating pattern of dark and light bands 1 nanometre in width. The thylakoid lipid bilayer is similar to prokaryotic membranes and the inner chloroplast membrane.
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During photosynthesis in a eukaryotic cell, an electrochemical gradient is formed across the _Thylakoid membrane in the mitochondria_.
An ion that may flow across a membrane typically exhibits an electrochemical gradient, which is a gradient in electrochemical potential. The gradient is made up of two components: an electrical gradient and a chemical gradient, or a difference in charge across a membrane and solute concentration, respectively. What is the Thylakoid membrane?In chloroplasts and cyanobacteria, the light-dependent photosynthesis processes occur in thylakoids, which are membrane-bound structures that resemble sheets. Chlorophyll, which is present there and used to absorb light and utilize it for biological processes, is where it is found. Thylakoid is short for the pouch and has the -oid ending.Lamellae, another name for thylakoids, can also refer to the part of a thylakoid that joins grana.The water photolysis, electron transport chain, and ATP synthesis processes are all carried out in the thylakoid.The thylakoid membrane is the location of the light-dependent processes in photosynthesis because it contains photosynthetic pigments (such as chlorophyll). With a large surface area to volume ratio due to the stacked coil form of the grana, photosynthesis is made more efficient.To learn more about Thylakoid membrane, refer to:
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On the periodic table lithium and beryllium are in different groups which statement describes why the two elements are in different groups.
They have different number of electron shells.
They have different atomic numbers
They are different colors
They have a different number of electrons in their outer shell
Answer:
They have a different number of electrons in their outer shell
In a closed ecosystem carbon cannot be produced are used up true or false
This is where exhaled carbon dioxide and other waste products are effectively converted, either chemically or through photosynthesis, into products such as food, water and oxygen.
What is a closed ecosystem?
Closed systems are characterized as 'self-regenerating' ecosystems that can sustain life without external help. By creating a continuous cycle, all resources can be fully reused.
It is primarily used to describe miniature forms of human-made ecosystems and is of scientific interest. These ecosystems tend to show great potential, especially in establishing life support systems during spaceflights and on space stations, and even in creating space habitats.
In closed ecosystems, it is important to naturally include at least one autotroph, since almost all designed closed ecosystems are based on autotrophs such as green algae. It is also important that all forms of waste produced by one organism are utilized by other organisms within a closed ecosystem.
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please help im timed
Answer:
Elements with the same number of valence electrons have similar chemical properties.
Explanation:
This is because the valence electron number decides the reactivity and bonding capabilities of an atom.
Write a paragraph explaining how nucleic acids and proteins work together to provide instructions for the structures and functions of an organism.
Answer:
Nucleic acids, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), carry genetic information which is read in cells to make the RNA and proteins by which living things function. The well-known structure of the DNA double helix allows this information to be copied and passed on to the next generation.
Explanation: i know.
Answer:
The nucleic acids contain the instructions for everything else on what to do, they go to the proteins and then kind of mix, they then go throughout the cell feeding it, along with giving the instructions.
Explanation:
which of the following statements is NOT part of the cell theory A. cells can absorb food and oxygen B. cells are basic units of structure and function in living things C. All cells are produced from other cells D. All living things are composed of cells
scientists have confirmed by carbon dating that seeds dormant for up to 2000 years can successfully germinate. based on the requirements for germination, what research expedition should you join in order to retrieve some ancient but viable seeds?
(D) "A trip to the arid Dead Sea region, where your historian colleagues have found a storeroom of wax-sealed jars." is the research expedition should you join in order to retrieve some ancient but viable seeds.
The Dead Sea Scrolls were initially found in 1947 by Bedouin shepherds at Qumran in a lonely maze of caves. The Bedouin found several antique clay jars that had been wax-sealed. They still remain shrouded in mystery and contain biblical and other religious writings that were copied more than 2000 years ago and therefore is accurate to the carbon dating that seeds dormant for up to 2000 years can successfully germinate.
Between 1947 and 1956, the texts were found in 11 caves adjacent to Qumran. Few well-preserved scrolls, which typically only survive in fragments, were discovered in cylindrical jars, but many other neighboring caves yielded identical jars and lids without scrolls.
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Question correction:
Scientists have confirmed by carbon dating that seeds dormant for up to 2000 years can successfully germinate. Based on the requirements for germination, what research expedition should you join in order to retrieve some ancient but viable seeds?
A. A trip to Indonesia, where the civet cat eats and expels coffee beans, producing a gourmet coffee known as Kopi Luwak.
B. A trip to the Irish marsh, where wet peat creates anaerobic conditions, and your colleagues hope to unearth a bog mummy.
C. A trip to the Burgess Shale in Canada, where your paleontologist colleagues have found fossils from the Cambrian era.
D. A trip to the arid Dead Sea region, where your historian colleagues have found a storeroom of wax-sealed jars
Which is the application of scientific knowledge to solve problems or create new products?
curiosity
technology
inquiry
geology
NEED HELP ASAPPPP!!!!!!!!!!!
According to the research, the correct option is technology. Technology is the application of scientific knowledge to solve problems or create new products.
What is Technology?It is a knowledge that comes directly from the field of science to achieve a solution that allows human beings to solve a given problem.
In this sense, it is a process that uses a combination of scientific knowledge, in the design and definition of procedures to build new products or give it another function.
Therefore, we can conclude that technology is the application of a set of scientific knowledge to satisfy a need in a specific field.
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sea stars prefer to eat mussels. if sea stars aren't present, mussels outcompete most other species in the mid-intertidal and lessen biodiversity. sea stars are: sea stars prefer to eat mussels. if sea stars aren't present, mussels outcompete most other species in the mid-intertidal and lessen biodiversity. sea stars are: a community dominant. a keystone species. a weak competitor. a competitive dominant.
If sea stars are not present, then this causes the biodiversity to lessen, hence sea stars are a) keystone species.
In ecology, a keystone species can be described as a species that significantly impacts a particular ecosystem. The presence or absence of a keystone species can affect the entire biodiversity of an ecosystem.
In the case above, sea stars are the keystone species of the mid-intertidal ecosystem as they help to keep the biodiversity in check in that particular ecosystem. Removal of sea stars from this ecosystem causes mussels to increase and lessen the whole biodiversity. As the removal of sea stars is impacting the whole mid-intertidal ecosystem, hence sea stars are the keystone species.
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2. Hoag hopes that Dr. Potbury will inform him that the substance under his
fingernails is blood. When he is informed that this is not the circumstance, he is
desperate to know its true nature. Speculate as to what it could possibly be.
|
Robert A. Heinlein's "The Unpleasant Profession Of Jonathan Hoag"– things do not end nicely.due to an excessive passion of life,With fear and hope freed free,In a simple prayer of thanks, we thank.
Describe" unpleasant profession of Hoag"
Ted awakens to discover Cynthia seemingly in a coma.He covers every mirror in the apartment with paint after realizing that the dreams were accurate.The only physician he knows, Potbury, is immediately called to come see Cynthia.When Ted repeats the Sons of the Bird's catchphrase, "The Bird is Cruel!" to Potbury, he obsessively conceals his face, just like the Sons did. Potbury diagnoses her with lethargica gravis.Ted overpowers Potbury after realizing he is one of them and imprisons him in the restroom.Hoag answers the phone and arrives at the residence.Hoag claims that lethargica gravis is simply another name for "deep sleep" when told about Potbury.When they open the bathroom door, they discover Potbury is no longer there. He gives them a list of items to bring and departs, leaving them rather perplexed. Ted and Cynthia find Hoag there after arriving at the park with the fine dishes and wines he ordered.They enjoy an epicurean picnic while Hoag reveals that he is an art critic.Their entire world was conceptualized by a "artist" as a school project.In order to evaluate the experiences, critics live as regular people in the world without realizing they are critics.As Hoag notes, one such experience is eating and drinking, since the basic act of obtaining energy to survive had not previously been considered to be a "experience".Another is sex, which is initially dismissed as absurd before Hoag discovers that it forms the cornerstone of "the tragedy of human love" that he observes between two people. Ted and Cynthia have seen everything, including Hoag during the daytime, and it was all caused by the Sons of the Bird.To learn more about "The unpleasant profession" refer
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please help
how does the Smooth Endoplasmic Reticulum function work in a plant cell
4-5 sentences
thank you
Answer:
The endoplasmic reticulum can either be smooth or rough, and in general its function is to produce proteins for the rest of the cell to function. The rough endoplasmic reticulum has on it ribosomes, which are small, round organelles whose function it is to make those proteins.
meiosis is a continous process but we can think of it as taking place in two stages meiosis i and meiosis ii. describe the products of each stage. how do the product
A reduction division and an equatorial division make up meiosis. To create gametes, meiosis I and meiosis II are necessary.
Meiosis II resembles a mitotic division, whereas meiosis I is a special cell division that only happens in germ cells. Meiosis, which decreases chromosome counts from diploid to haploid, and conjugation (fertilisation), which restores the diploid state by joining two haploid cells, are the two opposing processes that make up this. Chromosome segregation and recombination are the two processes that meiosis uses to create variety. As in mitosis, sister chromatids (the two halves of a duplicated chromosome) still need to be separated. The homologous chromosomes, which an organism acquires from both of its parents and are similar but not identical, must also be separated.
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Curare is a plant extract used by indigenous tribes in central and south america as a paralyses poison for hunting. Curare binds to ach receptors, but does not open the associated channels. What process in the motor unit is affected by curare? how would this affect muscle contraction?.
It is widely used to suppress neuromuscular junction activation. At useful concentrations, curare can decrease muscle contraction without compromising mental function, else, it is lethal.
What is Curare?The first anesthetic paralytic, curare (also known as D-tubocurare), has been supplanted by more recent medications. Around 1940, it was added to anesthesia.
It is taken from the Strychnos toxifera plant. The term "curare" refers to a variety of plant-based alkaloid arrow poisons used by native populations in Central and South America. Curare, which is used as a paralyzing agent for hunting and medicinal purposes, only becomes active when directly contaminated by a poison dart or arrow or when administered intravenously.
Curare can cause serious bodily injury if consumed. A neurotransmitter called acetylcholine may be inhibited, and abnormal muscular relaxation may lead to muscle paralysis.
Curare weakens or paralyzes skeletal muscles by interfering with the passage of nerve impulses between the nerve axon and the mechanism of muscle cell contraction, according to study.
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Nitrification reactions carried out be bacteria as part of the nitrogen cycle cn be considered.
Nitrification reactions carried out by bacteria as part of the nitrogen cycle can be considered as nitrogen fixation.
The first phase in the nitrogen cycle is nitrogen fixation, which involves turning atmospheric nitrogen into ammonia. The second step, nitrification, involves turning ammonia into nitrates and nitrates.
What are Nitrification reactions?
The biological oxidation of ammonia to nitrite and subsequent oxidation of the nitrite to nitrate by different species is known as nitrification alternatively, comammox bacteria may directly oxidize ammonia to nitrate. The rate-limiting phase in nitrification is often the conversion of ammonia to nitrite. The nitrogen cycle in the soil goes through an essential stage called nitrification. Small populations of autotrophic bacteria and archaea carry out the aerobic nitrification process.
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What is the major non-covalent interaction that holds two strands together in a double helix?.
Answer:
Hydrogen bonds
Explanation:
What is the major non covalent interaction that holds two strands together in a double helix? The hydrogen bonds between the base pairs form the double helical structure of DNA. There is no exchange or sharing of electrons in hydrogen bonds as seen in covalent or ionic bonds.
in 1960 the united states had 16,000 km of interstate highways today the interstate high way system includes 77,000 km of paved roadways what percent does this represent
In 1960 the united states had 16,000 km of interstate highways today the interstate high way system includes 77,000 km of paved roadways. This represents the total increase of 38 % is shown in the data. Thus, option C is correct.
What is clinical support?The term clinical support has been defined as the model which has been arranged in such a manner that has been facilitated, contrast communication channel for everyone who does clinical activity with the patients. Clinical support has been much needed for the patients.
The practice of the clinical support has been performed by the clinical support worker and they perform their role very seriously to serve the patient because for them everything is patient's good health.
Therefore, In 1960 the united states had 16,000 km of interstate highways today the interstate high way system includes 77,000 km of paved roadways. This represents the total increase of 38 % is shown in the data. Thus, option C is correct.
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predict the following gene and genotypic frequencies for a gene at hardy-weinberg equilibrium within a population of animals where the gene frequency of the dominant allele is 0.9. assume two alleles exist for the gene within the population.
The predicted genotypic frequencies for an allele of gene at hardy-weinberg equilibrium within a population of animals where the gene frequency of the dominant allele is 0.9 is 0.18
Using the data supplied in the question,
Frequency of allele P = 0.9 or 90%,
Frequency of allele p = 0.1 or 10%.
From Hardy-Weinberg equilibrium : (p^2 + 2pq + q^2)
2pq (Heterozygous genotype) = 2 x 0.9 x 0.1 = 0.18 or 18%
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