Answer:
B. Corundum
Explanation:
Using the Mohs scale of hardness, the mineral has a hardness greater than 6.5 (Steel nail) but less than 8.5 (Drill bit). The corundum has a hardness of 9.0, which means it cannot be scratched by a drill bit, but all the other choices have a hardness scale less than 6.5 but the mineral was not scratched by the nail. So the best answer would be B.
Based on the given information,corundum is a mineral that can't be scratched by a steel nail but can be scratched by a masonry drill bit.The correct option is B.
Minerals are defined as a chemical compound which has a well -defined composition and possesses a specific crystal structure.It occurs naturally in the pure form.
If a compound occurs naturally in different crystal structure then each structure is considered as a different mineral.The chemical composition of a mineral varies depending on the presence of small impurities which are present in small quantities.
Using the Mohs scale of hardness, mineral hardness is determined.The hardness of steel nail is 6.5 and that of drill bit is 8.5 . The corundum has a hardness of 9.0, which means it cannot be scratched by a drill bit, but all the other choices have a hardness scale less than 6.5 but the mineral was not scratched by the nail.
Thus, option B is correct.
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Under capitalism, the allocation of goods and services is determined by ________________________________.
consumers.
the government.
businesses.
free market forces.
Answer:
I believe it's D.
Explanation:
Hope my answer has helped you!
Answer:
businesses
Explanation:
What does an electrocardiogram measure?
A) Sound waves created by the closing of heart valves
B) The volume of blood moving through the heart chambers
C) The force of muscle contraction in the heart chambers
D) Action potentials moving through the heart muscle
Where is a bacterial cell's DNA found?1. ribosomes2. nucleus3. peroxisome4. nucleoid region5. capsule
Answer:
nucleoid region
Explanation:
The amount of radioactive isotopes contributing heat to Earth is greater now than it was when Earth was newly formed.
Question 20 options:
True
False
Answer:
false
Explanation:
The amount of radioactive isotopes contributing heat to Earth is less now than when Earth was newly formed because these isotopes have decayed over time, making the statement false.
The statement that the amount of radioactive isotopes contributing heat to Earth is greater now than it was when Earth was newly formed is false. Radioactive isotopes such as 238U, 235U, 40K, and 232Th have been providing heat to Earth's interior through radioactive decay. Initially, there were more of these isotopes when Earth was young, making the radioactive contributions and resulting heat greater. These isotopes decay over time, reducing their quantity and the heat they produce. Presently, the heat produced by radioactive decay is roughly 25% of what it was at Earth's formation.
Additionally, Earth's heat also comes from the initial deposit of heat left over from its formation and accretion, with energy contributions from impacts such as the one from Theia, which led to the creation of the Moon. However, it's the radioactive decay of primordial elements that still significantly contributes to Earth's internal heat, albeit less so than when Earth first formed.
A sign of global warming and general climate change would be?
Answer:
It is B the one your already on
Explanation:
We live in the Cenozoic era, and scientists know more about this era and the epochs it's divided into than any other time period. Why is this?
Scientists have a better understanding of the Cenozoic Era, the era we live in, because it is the most recent and its geological record is well-preserved, containing clear evidence of past life forms, including mammals' rise to dominance after dinosaurs' extinction.
We live in the Phanerozoic eon, within the Cenozoic era, which is known as the Age of Mammals. This era is divided into different periods and epochs, including the Quarternary period and the Holocene epoch. The Cenozoic era began about 65 million years ago and continues to present day. It's characterized by the emergence and dominance of mammals, including human ancestors, after the extinction of dinosaurs.
Scientists know more about the Cenozoic era than any other time period because it is the most recent and therefore the best preserved in the geological record. During the Cenozoic, most of the organisms that we share Earth with evolved. Additionally, the closer proximity in time allows for better preservation and study of fossils, giving us clearer evidence of past life forms and environments.
Throughout the Cenozoic, Earth experienced significant climatic and geographical changes, such as the ice ages and tectonic shifts. These shifts contributed to the evolution and distribution of species. The ongoing nature of these changes, as well as human interest in understanding our own origins, drives the in-depth study of this era.
Modern computers can store about as much information as the human brain. True False
its false I took the test
Which part of an angiosperm contains seeds?
leaf
fruit
spore
pine cone
Study the image of this rock.
Which word best describes the rock's grain shape?
O jagged
O oval
round
ON
O smooth
Answer:
jagged
Explanation:
I have made a synthetic cell by placing a solution that is 10% sodium chloride inside a semipermeable membrane through which water can pass but not sodium chloride. If I place this cell into a solution that is 20% sodium chloride what will happen to the size of the cell? will it increase, decrease, or stay the same in size?
What form of anesthetic was used for field surgery
Answer: Anesthesia
Explanation:
Anesthesia was used in 95% of Civil War surgeries. Sulfuric ether had been discovered in Europe in the 1830's and was first used as an anesthetic by William Morton in 1846. After a successful public demonstration it became widely used in surgery.
This is a map that shows hot spots around the world.
Which phrases describe the formation of the Hawaiian
Islands? Check all that apply.
formed due to subduction
Iceland
formed in the middle of a plate
Yellowstone
Azores
Hawaii
formed at a divergent boundary
formed at a convergent boundary
Galapagos
formed where mantle erupts through crust
Answer:
- formed in the middle of a plate
- formed where mantle erupts through crust
Explanation:
The Hawaii Islands are a chain of volcanic islands. They have been formed by a hot-spot in the middle of an oceanic plate, the Pacific tectonic plate. The convection currents in the mantle are much stronger in this part, and it manages to easily break through the crust. As it does, the magma from the mantle has been rising the seafloor and as it was going up it emerged above the surface of the water, resulting in the formation of volcanic islands. Because the plate is moving over the hot-spot, the volcanoes are moved away and detached from the hot-spot, so they stop being active. The hot-spot though continues to propel magma upwards, so it forms new volcanic island, and the process goes on and on, so a chain of numerous volcanic islands is formed, and maybe a new continent in the future.
Answer:
- formed in the middle of a plate
- formed where mantle erupts through the crust
A scientist separates a population of mice into two groups. what would most likely increase the rate of speciation in this population.
A. Teach the two groups different tricks
B. Allow the two groups to breed with each other
C. Put the two groups in different environment
D. Have the two groups live in identical ecosystems
Answer:
C
If you put the 2 rats in different environments, you will not only observe the adaptations they use to survive in different environments, but what consequences will occur if they are in a unfamiliar environment
Answer: C. Put the two groups in different environment.
Explanation:
Speciation is the process in which new species develop from the parent or pre-existing species in due course of evolution. The following are the types of speciation.
1. Allopatric speciation: This results when the two populations of the same species, are separated geographically.
2. Sympatric speciation: This results when the two populations living in the same area diverge due to changes in the behavior, morphology and in genomic level. This results in reproductive isolation among members of the same species belonging to two distinct populations.
Among the options given, C. Put the two groups in different environment. is the correct option. This is because of the fact that this will favor allopatric speciation. As due to geographical barrier, the separated groups will develop traits different from the parent species. Hence, result in development of new species.
Many plants respond to changes in day length because of __________________. translocation a pigment that is sensitive to the amount of darkness a specialized stoma that responds to changes in light and darkness an electronic sensor in their leaves
Answer:
a specialized stoma that responds to changes in light
Explanation:
This is the only one that makes sense because an electronic sensor is totally wrong, and translocation definition is the movement of something from one place to another.
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Which of the following statements is considered true of Neanderthals? A. They had some system of religious beliefs about afterlife. B. They had smaller brains than homo sapiens (modern humans). C. They evolved into homo sapiens. D. They emerged after the ice age.
Answer:
A. They had some system of religious beliefs about afterlife
Explanation:
The Neanderthals are one of the closest cousins to the modern humans, in fact, lot of people in Europe and Asia have small percentage of Neanderthal gene in them. Unlike the popular belief, the Neanderthals were not stupid, bulky, primitives, but instead they were much more evolved, had very large brain capacity, created art, and it is believed that they even had some system of religious beliefs about afterlife. The clue for the supposed system of religious beliefs about afterlife comes from a burial site, where a Neanderthal was buried with an ax, thus a weapon. When comparing such action with the human behavior, it resembles a lot to the ancient human beliefs about afterlife, where weapons and other objects were commonly left in the graves.
Answer:
They had some system of religious beliefs about the afterlife.
Explanation:
PENN
What characteristic of radioactive decay makes it useful for determining the absolute age of samples?
Question 10 options:
occurs at a constant rate
changes based on temperature
speeds up under high pressure
slows down in very dense samples
Answer:
occurs at a constant rate
Answer:
Option A, occurs at a constant rate
Explanation:
It becomes easy to determine the age of any radioactive substance when the rate of decay is constant and its starting and presents mass is known.
For example - if we know that the mass of a radioactive substance is 100 Kg few years back , but its present mass is 10 Kg. Then if we know the value of rate of decay, we can easily determine the age of substance based on the logarithmic equation as given below
[tex]A_t= A_0*e^{kt}[/tex]
Where [tex]A_t[/tex] is the mass of radioactive substance at time t
[tex]A_0[/tex] is the mass of radioactive substance at time [tex]t=0[/tex]
t is the time in years and
k is the decay constant.
Hence, option A is correct.
1.
Double-ringed bases are ________.
purines
exempt from Chargaff's Rules
complementary with each other
pyrimidines
2.
Which of the following is not a characteristic of Chargaff’s Rule #1?
is also termed Chargaff's ratio
states that T = A and G = C
states that DNA composition varies among species
states that the ratio of adenine to thymine is equal, as is the ratio of guanine to cytosine
3.
What type of bonds are formed between complementary bases?
triple carbon to carbon bonds
hydrogen bonds
ionic bonds
polar covalent bonds
4.
_______ are single-ringed bases.
guanines
adenines
purines
pyrimidines
Answer:
1. Purines
2. States that DNA composition varies among species
3. Hydrogen Bond
4. Purines
Answer to #2 is a little iffy -- sorry
Explanation:
Pyrmidines have two rings
Purines have one ring
Complementary bases are connected by hydrogen bonds.
Final answer:
Double-ringed bases are purines, and Chargaff’s Rule #1 states that T = A and G = C, but it is not termed Chargaff's ratio. Complementary bases in DNA are connected by hydrogen bonds, and single-ringed bases are called pyrimidines.
Explanation:
1. Double-ringed bases are called purines.
2. A characteristic of Chargaff’s Rule #1 that is not accurate is that it is also termed Chargaff's ratio. The rule correctly states that T = A and G = C, and that DNA composition varies among species, as well as that the ratio of adenine to thymine is equal, as is the ratio of guanine to cytosine.
3. The type of bonds formed between complementary bases are hydrogen bonds.
4. Single-ringed bases are known as pyrimidines, which include cytosine (C) and thymine (T).
Which of the following are indications for using parenteral nutrition? Select all that apply.
a. Paralytic ileus
b. Severe short bowel syndrome
c. Dysphagia
d. Coma
e. Good peripheral veins
f. Need for more kilocalories and nutrients
Answer:
tippy for my bung hole
Explanation:
tpppp my bung hole
Patients who are unable to maintain a sufficient oral intake of food or nourishment to meet their metabolic needs should have enteral tube feeding. Enteral feeding is frequently used by medical professionals with individuals who have dysphagia. Thus option A, B,C,F is correct.
What indications for using parenteral nutrition?Patients may require PN for a wide range of illnesses or conditions that affect nutrient digestion, absorption, or food intake.
Short bowel syndrome, GI fistulas, intestinal obstruction, critically ill patients, and severe acute pancreatitis are a few diseases and circumstances where PN is recommended.
Candidates for PN include critically ill individuals who cannot get enteral nourishment and whose nothing-by-mouth condition will persist longer than 4 to 5 days.
Therefore, Paralytic ileus, Severe short bowel syndrome, Dysphagia, Need for more kilocalories and nutrients are indications for using parenteral nutrition.
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I need some help everybody.
The production of cells during mitosis into specialized function is called: recombination or differentiation
Answer:
recombination
Explanation:
Recombination occurs when two molecules of DNA exchange pieces of their genetic material with each other. One of the most notable examples of recombination takes place during meiosis (specifically, during prophase I), when homologous chromosomes line up in pairs and swap segments of DNA.
What organs comprise the respiratory system of a bird
Answer:
Paired lungs
Explanation:
Paired lungs comprise the respiratory system of a bird.
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_____ are surface appendages that allow a bacterium to stick to a surface.1. Ribosomes2. Mitochondria3. Fimbriae4. Flagella5. Cell walls
Fimbriae are surface appendages that allow a bacterium to stick to a surface.
What is fimbriae?Fimbriae are defined as the long filamentous polymeric protein structures located at the surface of bacterial cells. They enable the bacteria to bind to specific receptor structures and thereby colonize specific surfaces.A bordering fringe especially at the entrance of the fallopian tubes. A join of nerve fibers bordering the hippocampus and joining the fornix.The fimbriae are a smaller version of pili. They are short appendages-like structures present on the surface of the cell wall of many gram-negative bacteria.To learn more about fimbriae refer to:
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PLEASE HELP
The two parts of tRNA molecule that function in protein synthesis are ____.
a. an anticodon and an amino acid
b. its shape and size
c. its base pair sequence and its loops
d. a start codon and a stop codon
Answer: a. an anticodon and an amino acid
Explanation:
The following is a typical structure The tRNA where we can observe an anticodon that binds to the nucleotide sequence of the mRNA and an amino acid that in triplet encodes for an protein.
Infants and young toddlers find it more difficult to recover from brain damage than adults because their brain has not developed plasticity yet.
Answer:
False
Explanation:
If it is a T or F questions then yes it is false.
Contrary to the misconception, infants and young children have a high capacity for brain recovery due to neural plasticity, which allows the brain to form new neural connections.
Neural plasticity refers to the brain's ability to reorganize itself by forming new neural connections throughout life. For instance, when an infant suffers damage to the temporal lobe's facial recognition areas, although they may face challenges, the brain's ability to adapt is still significant.
Neuroplasticity continues into adulthood, although its effects may be less pronounced compared to those in children. Adult brains can still rewire to compensate for injury and change in response to experiences, which is evident in cases such as accomplished musicians displaying larger auditory cortexes or requiring less neural activity for finger movements. Despite these adaptive capabilities, some conditions like neurodegenerative diseases do pose much greater challenges and may not show strong evidence of the brain's capacity to recover.
What is a phospholipid composed of?
a. a nonpolar head and a polar tail
b. a nonpolar head and tail
c. a polar head and a nonpolar tail
d. a polar head and tail
A phospholipid is composed of a polar head and a nonpolar tail. These components allow it to form a bilayer in cell membranes.
The correct option is c.
Explanation:A phospholipid is composed of a polar head and a nonpolar tail. The polar head is hydrophilic (water-loving), which means it is attracted to water.
The nonpolar tail, on the other hand, is hydrophobic (water-fearing), and not attracted to water.
This configuration makes phospholipids the perfect building block for cell membranes, and results in the formation of a phospholipid bilayer when in aqueous solutions, allowing them to separate the inside of a cell from its outside environment.
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How often does the total volume of blood circulate through the system?
Answer:
obese kids per happy meal
Explanation: ok/hm
Which number represents a basic pH, 4 or 9? _______
Numerical Answers Expected!
Answer for Blank 1:
I'll give brainly
Answer:
9
Explanation:
Any pH value above 7.0 is that of a base. Below that value is the pH of an acid.
its 9 i got it right on my test.
Under the Soviet system, the government a. controlled all forms of communication. b. allowed newspapers to print whatever they wanted. c. controlled editorials but not the reporting of news. d. encouraged access to a wide variety of news sources. Please select the best answer from the choices provided A B C D
Answer:
A controlled all forms of communication
Explanation:
Photosynthesis occurs in both prokaryotes and eukaryotes.How do the location where photosynthesis occurs differ in prokaryotes and eukaryotes?
Answer:
In eukaryotes, it occurs in the chloroplast. In prokaryotes it does it in the cytoplasm.
Explanation:
Prokaryotes don't have organelles such as the mitochondria and the chloroplast, it just has cell membrane, which its only function is to protect the cell and is unable to generate chemical processes; the DNA, which stores and manages only the genes, which would be affected if exposed to a chemical process like photosynthesis; and the cytoplasm, which stores the materials that the cell needs, where photosynthesis occurs. Eukaryotes have chloroplasts, which absorb the sunlight and combine it with carbon dioxide and water to realize photosynthesis.
Answer:
C
Explanation:
it right on edmentum
Why is active transport necessary for the sodium-potassium pump to work?
A. All channel movement requires active transport to equalize the cell
B. It allows sodium and potassium to move against their concentration gradient
C. The potassium would never leave a cell while sodium can move against the gradient
D. The sodium would never leave a cell while potassium can move against the gradient
Answer:
A. All channel movement requires active transport to equalize the cell
Explanation:
Active transport is necessary for the sodium-potassium pump to work because all channel movement requires active transport to equalize the cell.
Answer:
B. It allows sodium and potassium to move against their concentration gradient
Explanation:
The role of sodium and potassium pump in the body is to help move ions against their concentration gradient. There are two types of transport (1) active transport (2) passive transport.
Passive transport is a natural phenomenon in which ions move from high concentration to lower concentration. In such transport no ATP/energy is required. In contrast to this, active transport is a kind of transport which occurs against concentration gradient and in order to facilitate this opposite movement of ions they require ATP/energy input. Sodium and potassium pumps perform active transport in our body. In neurons they play an important role of ion exchange. They move sodium and potassium ions against their concentration gradient for which they require ATP and thus help in basic functioning of neurons.
Hearing the word rabbit may lead people to spell the spoken word hair as h-a-r-e. This best illustrates the outcome of a process known as
Answer:
D. Priming.
Explanation:
Final answer:
The process where hearing the word 'rabbit' influences the spelling of 'hair' as 'hare' is known as semantic priming, a cognitive process where one stimulus affects the response to another.
Explanation:
The scenario described in the question where hearing the word rabbit may lead people to spell the word hair as hare is an example of a cognitive linguistic process. This process is known as semantic priming, where exposure to one stimulus influences a response to a subsequent stimulus, without conscious guidance or intention. In this case, hearing 'rabbit' activates associated words and their spellings, which can influence how someone spells a similar-sounding word, leading them to choose 'hare' instead of 'hair'. Semantic priming is part of our cognitive processes and how we interpret and produce language.