What is the percent yield of the reaction below if 84.0 grams of Al2O3(s) is recovered from a reaction whose theoretical yield of Al2O3(s) is 104 grams?
4 Al(s) + 3 O2(g) → 2 Al2O3(s)

Answers

Answer 1

Answer:

is that 23% ..

.. according to my knowledge


Related Questions

Unlike other plants, trees are plants living for several years thus they are

A. Annual

B.shade

C.perennial

D. Fence

Answers

c. perennial

hope this helps!

predators are... a. primary producers b. primary consumers c. secondary consumers

Answers

Answer:

Primary consumers

They eat the majority of prey

Do you think that Neanderthals deserve the sometimes negative public image they have?

Answers

Answer:

No.

Explanation:

Neanderthals are portrayed as idiotic animals while in reality they are the beginning of our civilizations. While yes we are far more advanced then they were back then they are still our beginning roots and were smart enough to take the first steps towards advancement causing us to be where we are now :)

HELP ASAP!!!! 50 points!!
In this task, you’ll record the direction of a compass as it’s placed at different points around a magnet. The investigation will try to answer the question, Do two magnets create magnetic force fields that allow them to interact without touching?
Part D :
How might someone dispute the results of this investigation? How might you counter the argument?

Answers

Answer:

It could be argued that there is a separate force acting upon the investigation. Or that the room is invalidating the results for some reason. Or that an error was made in measurement.

There are a thousand and one ways to try to dispute an investigation like this. However, for every argument that can oppose it, a counterargument can easily be made.

For instance, controlling the variables invalidates about 90% of any possible claims to the contrary. The majority of arguments would stem from the fact that it is nearly impossible to completely prove something in fear of external factors. The solution? Control the external factors.

So, in conclusion, a person could dispute the results of the investigation by claiming that something invisible like magnetics could not possibly be proven to exist, because there are all sorts of things that could be influencing the investigation. The way to counter the argument would be to prove yourself that the environment is controlled, and that nothing could be influencing the investigation.

Answer:

guy ontop is correct

Explanation:

describe the cell membrane, cell wall, nucleus, and cytoplasm. which of these structures are you likely to find in a prokaryotic cell? eukaryotic cell? plant cell? animal cell?

12 points! please answer asap!

Answers

Answer:

you can see below

Explanation:

Basic Definitions:

Cell Membrane = the semi-permeable structure that surrounds the cell and keeps all of the cells organelles from exploding everywhere.

Cell Wall = the rigid 'armor' of the cell that surrounds it after the membrane. Usually made up of cellulose and ONLY found in plant cells.

Nucleus = A really dense organelle of the cell usually surrounded by two membranes. They contain and protect your genetic material. Basically everything that makes you, you.

Cytoplasm = The watery, salty, and protein filled 'soup' that fills the cell. All organelles float happily in this.

Now Specific Locations:

Eukaryotic cells

have plasma membranes

please mark me brainliest or mark me thanks at leat

only have cell walls if the cells are plants.

They do have a nucleus.

They have cytoplasm

Prokaryotic cells

have plasma membranes

cell walls are usually chemically complexed.

don't have a nucleus

have cytoplasm

Animal cells

only have the plasma membranes.

No cell wall

have a nucleus

have cytoplasm

Plant cells

have both the cell wall

and have a plasma membrane

have a nucleus

have cytoplasm

Dark skin ( a result of increased melanin production in equatorial populations), is likely a response to ultraviolet radiation because UV radiation causes:

Answers

Answer: Skin cancer

Explanation:

Melanin is a pigment derived from an amino called acid tyrosine. The most common form of melanin is called eumelanin, which is a polymer of dihydroxyindole carboxylic acids and their reduced forms. When a person is exposed to the ultraviolet light (UV) from the sun, the melanocytes will produce eumelanin to prevent the skin from burning and damage to the cell nuclei (where DNA is found) of the epidermis. This melanin production causes the skin to darken. The eumelanin in the skin then acts as a natural sunscreen by blocking the damaging effects of sunlight. So, skin darkens when exposed UV light, thus providing greater protection when needed by producing more eumelanin, but it also becomes more likely to develop melanoma, which is a type of skin cancer. This is because UV rays damage the DNA of skin cells. The DNA (deoxyribonucleic acid) is the genetic material that has the instructios to the growth and functioning of an organisms). Skin cancers begin when eumelanin protection is not sufficient and this damage affects the DNA of the genes that control the growth of skin cells. This results in a tumor, which is the uncontrolled growth of cells (in this case, skin cells) because there will be a mutation in DNA that affects the function of the cells.

Whic type of graph would you use if you wanted to see if one variable had an affect on another variable?

Answers

A scatter plot or scattergram chart will show the relationship between two different variables or it can reveal the distribution trends. It should be used when there are many different data points, and you want to highlight similarities in the data set.

Answer:

line

Explanation:

A line graph is used to see if there is a relationship between variables.

Select the correct answer
Which term refers to the maximum number of organisms of a particular species that can be supported by an environment?
OA Population density
OB Exponential growth
OG carrying capacity

Answers

Answer:

Carrying capacity

Explanation:

Carrying capacity means the number of organisms that a region can support without environmental degradation.

A mutation is identified in a tumor sequencing study. Which of the following pieces of evidence would most strongly suggest that the mutation is a passenger mutation?
a. The same gene is mutated in many other individuals with the same kind of cancer.
b. The mutation impacts the function of a known tumor suppressor gene.
c. The mutation is a silent point mutation in a protein-coding sequence.
d. The gene carrying the mutation is known to participate in the cell cycle.

Answers

Answer:

The mutation is a silent point mutation in a protein-coding sequence.

Explanation:

A mutation is a change or alteration in DNI sequences that introduce new variants. Many of these are eliminated, but some of them might succeed and be incorporated into each individual. Mutations can be damaging or beneficial.

There are two types of mutations in cancerous cells:

· Driver mutations, which refer to genetic changes that provide malign cells an adaptative advantage. These mutations drive the cells to tumoral evolution.

· Passenger mutations, also known as neutral mutations, refer to those that do not provide any advantage nor disadvantage to the cancerous cell. These mutations can be between DNI segments where the driver mutations are. Some of these passenger mutations might become driver mutations with time.    

Which of the following events contributes to the termination of a signal generated by the binding of a ligand to a receptor tyrosine kinase? Only one answer is correct
1. Phosphatases hydrolyze key phosphorylated residues.
2. Kinases hydrolyze key phosphorylated residues.
3. Kinases phosphorylate key residues.
4. The receptor tyrosine kinase dimerizes.
5. GTPase removes a phosphoryl group from GTP.
6. Phosphatases phosphorylate key residues.

Answers

Answer:

1. Phosphatases hydrolyze key phosphorylated residues.

Explanation:

Receptor Tyrosine Kinases (RTKs) are high-affinity transmembrane protein receptors that bind to a wide variety of ligands (e.g., growth factors, cytokines, hormones). These receptors (RTKs) have a transmembrane domain and therefore these proteins act as membrane receptors, as well as exhibit catalytic activity. The intracellular C terminal region of RTKs contains catalytic domains responsible for both autophosphorylation and tyrosine phosphorylation of their protein substrates. Moreover, Protein Tyrosine Phosphatase (PTPs) are critical enzymes that remove phosphate groups from tyrosine residues in different substrates (including RTKs), thereby regulating key signaling pathways such as cell proliferation, cell differentiation, and cell-cell adhesion.

Fill in the blanks: Antibodies are produced by _______________________________________ and bind to specific ________________________________ on erythrocytes, causing ________________________________, or clumping of erythrocytes.

Answers

Answer:

Antibodies are produced by _white cells__ and bind to specific _antigens_ on erythrocytes, causing __agglutination__, or clumping of erythrocytes.

Explanation:  

Macrophages are one of the different types of cells that intervene in the organism's defense system against strange substances and pathogen agents. These cells are the principal actors in the immune response.

Macrophages have several functions. They are the principal phagocytes of tissues, capable of recognizing different strange molecules that penetrate the organism, such as bacterias, parasites and, viruses. Macrophages phagocyte these substances and eliminate them, a process known as phagocytosis. When macrophages are activated, they release cytokines that favor inflammation response, which is used to neutralize the pathogen agent. When macrophages phagocyte strange substances, they show the antigens in their surfaces to be recognized by lymphocytes.

Antigens are defined as the strange substances that enter the organism and trigger a series of cellular events that produce defense mechanisms. Antibodies recognize antigens as invaders.  

In the organism, there are leucocytes or lymphocytes (white cells) in charge of immune defense. These are B cells, which produce antibodies, and T cells that can destroy infected cells from the body. They all circulate in the blood.

Antibodies are globular proteins produced by lymphocytes in response to the presence of strange molecules. Each type of antibody recognizes and combines with a particular antigen, immobilizing it. After that, the antigen is destroyed by other components of the immune system.

Describe the unique anatomical features of cardiac muscle. What role does the unique structure of cardiac muscle play in its function

Answers

Answer:

The cardiac muscle is made up of branched muscle cells, which have 1 or 2 nuclei and which the contact area between the heart fibers gives rise to specialized regions at the level of the plasma membrane called intercalary discs. The intercalary discs unite the cardiac muscle cells with each other, which provides greater adhesion to the tissue and intervenes in the rapid communication between cells. This allows its simultaneous contraction and the production of the beat.

Explanation:

The intercalary discs are the union systems that associate the cardiac muscle cells to form the myocardial fibers, the cardiac muscle is the muscle tissue of mixed components, which is located exclusively in the walls of the heart. For this reason, it has the function of generating the necessary contractions for the blood to reach all parts of the body.The intercalary discs are a special type of intercellular junction, a gap that guarantees electrical communication between these cells; and on the other hand, it provides places of adhesion and anchorage of one cell with another. The intercalary discs provide the structural foundation that allows the heart to behave as a functional syncytium.

A true reversion occurs when the wild-type DNA sequence is restored to encode its original message by a second mutation at the same site or within the same codon. Which of the following isoleucine codon(s) could be mutated once to form a methionine codon, and then mutated at a second site to restore an isoleucine codon?
A. AUC.
B. AUU.
C. AUA.
D. None of these codons.

Answers

Answer:

The correct answer is option d- none of these.

Explanation:

The genetic code for methionne is AUG and genetic code for isoleucine are AUC, AUA, AUU. As we can see that there are first two codons are similar for both methionine and isoleucine.

So mutation at to any other site other than third psostion not possible that can convert isoleucine to methionine and this same mutation site is the only mutation position mutation can revere back methionine to isoleucine.

Thus, none of the given can restore an isoleucine codon.

what must be true about two objects if heat is flowing between them​

Answers

Answer:

The objects must be the same temperature.

Explanation:

if heat is flowing between two objects, so both ​the objects must have the same temperature because the heat in object 1 passes to the object 2 due to the conduction property present in these objects. The heat flows from one body to another body until both have the same amount of heat energy as well as temperature so that's why we can say that both objects must be the same temperature.

explain water cycle with the help of diagram​

Answers

Explanation:

The water cycle is defined as a natural process of constantly recycling the water in the atmosphere. It is also known as the hydrological cycle or the hydrologic cycle. During the process of the water cycle between the earth and the atmosphere, water changes into three states of matter – solid, liquid and gas.

hope it helps.stay safe healthy and happy...

what's the target cells of melatonin?​

Answers

Explanation:

The suprachiasmatic nucleus appears as a target of melatonin in mammals.The pineal hormone may thus be involved in a feedback loop of the mammalian photoneuroendocrine system.

is it possible that after the first meeting of male and female through sexual inter course
the female become pregnant after the sex??​

Answers

Answer:

Yes, it is possible because, if the sperm from the male goes into the egg of the female it can cause the female to get pregnant by that male. And its very rare for the female not to get pregnant after having inter course with the male. That's only if they had unprotected sex.

I hope this helps you!

XoXo Mashayla

Explanation:

explain the importance of studying cytology ​

Answers

the importance of studying cytology are

Explanation:

Cytology is important in modern-day medicine as well. Cytological tests are used to observe human cells to determine the risk of abnormalities and cancer. The Pap smear test looks at cells as opposed to pieces of tissue and is used to screen women for cervical cancer.i hope it will help you

All claims in science should be supported by

Answers

Evidence

Hope this helps. Have a great day! :)

In pea plants, flowers are either white or purple: the purple color is produced by pigments called anthocyanins. The production of anthocyanins is a two-step process: the first step is controlled by the C gene and the second by the P gene. Both genes must produce functional proteins for anthocyanin to be produced. This is an example of:

Answers

Answer:

This is an example of gene translation.

Explanation:

Gene translation refers to the genetic process where a set of genes is used to create amino acids that will be responsible for creating a protein needed to perform some function or characteristic of the organism. In the question above, we can see that anthocyanin, responsible for the pigment of flowers, is created through the work of proteins that are created from gebes C and P. This is an example of gene translation, as it presents the formation of proteins regulated by genes.

Por qué algunas enfermedades se padecen solo una vez?

Answers

Answer:

por que a mi saber, cuando te infectas con una enfermedad viral al contagiarte y después sanar tu cuerpo crea anticuerpos que estos asu vez hacen que seas inmune a ese virus y otras veces las enfermedades son erradicadas con la vacunación.

why your 21st century sophisticated, how do you explain the role of the plant in the change of the air in the jar​

Answers

Answer: The gas of Fire constrains the atoms that make up oxygen in the air. Plants release oxygen, and take in carbon dioxide.

Natural selection is most likely to be the cause of a change in a population's
allele frequencies when:
A. the ecosystem experiences few disturbances,
B. the population drops below its carrying capacity.
C. the predators are removed from the ecosystem,
D. the population has reached its carrying capacity.
PLEASE HELP URGENT

Answers

Answer:handheld c

Explanation:bend c smlOc

C is probably the right answer to me

The coding RNA in a cell at particular time is comprised of
A. total mature mRNA
B.whole RNA
C. hnRNA
D.4% of total coding RNA

Answers

B whole RNA that is the correct answer

Provide details about Meiosis.

Answers

Explanation:

a type of cell division that results in four daughters cells each with half the numbers of chromosomes of the parent cell , as in the production of gametes and plant spores

Drag each of the following labels into the appropriate box to identify which motor division of the peripheral nervous system is identified by the given function.an be excitatory or inhibitory on the target organ Principally involved with movement of materials through the body Skeletal muscle activation Intestinal smooth muscle activation Voluntary Sweat gland activation Lacrimal gland activation Principally involved with movement "of" the body principally invvedPiloerector muscle Involuntary activation Somatic Autonomic

Answers

Answer:

Somatic: Skeletal muscle activation VoluntaryPrincipally involved with movement "of" the body.Autonomic: Can be excitatory or inhibitory on the target organ. Principally involved with the movement of materials through the body. Intestinal smooth muscle activation. Sweat gland activation Lacrimal gland activation Piloerector muscle Involuntary activation.

Explanation:

We can divide the nervous system into the central nervous system, which consists of the brain and spinal cord, and the peripheral nervous system, which consists of all the nerves that are throughout the body carrying information from and to the central nervous system.

We divide the peripheral nervous system into the somatic nervous system and the autonomic nervous system.

The somatic nervous system is the conscious one, that is to say, that we know and control what it does. It is voluntary. It has motor and sensory neurons that carry information to and from the central nervous system. The somatic nervous system is the one that makes us move our muscles to do an action.

The autonomic nervous system is involuntary. In other words, we can not control it consciously. It is the one that controls glands, organs, and smooth muscle, like the one that surrounds the digestive tract to move the food. As we can not consciously control it, this system can work exiting or inhibiting an organ depending on the situation.

The  peripheral nervous system is simply divided into 2 types, which are the somatic nervous system and the autonomic nervous system.

SOMATIC

Voluntary principally involved with movement "of" body skeletal muscles activation

AUTONOMIC

Involuntary lacrimal gland activation intestinal smooth muscle activation principally involved with movement "through" body sweat gland activation arrector pili activation can be excitatory or inhibitory on target organ

The peripheral nervous system (PNS) is the simply known as the division of the nervous system that has all the nerves that is found outside of the central nervous system (CNS).

Its primary role is to connect the central nervous system to various organs such as the limbs, and skin.  simply divided into 2 types, which are the somatic nervous system and the autonomic nervous system.

Learn more from

https://brainly.com/question/10802414

Enter the sequence of the DNA coding strand with a 5-3 polarity. DO NOT WRITE 5 OR 3 OR 5' OR 3' IN THE BOX!

Answers

Complete question:

Use the sequence below to answer the following questions  

3’-ACGGATCCTCCCTAGTGCGTAATACG-5’  

5’-TGCCTAGGAGGGATCACGCATTATGC-3’  

1. Enter the sequence of the coding strand with a 5’-3’ polarity

Answer:

coding strand → 5´- GCATAATGCGTGATCCCTAGGCA -3´

Explanation:

When referring to the coding strand, we are talking about the sequence that turns to be the same as the mRNA that results from the transcription of the same DNI segment -switching bases T for U-.  

The coding strand receives that name because it is the sequence that codes for each amino acid composing the proteins.

When the DNI molecule separates into two strands to form the transcription bubble, we can identify two separate segments: coding strand and template strand.  

The coding strand goes in direction 5´ to 3´, while the complementary strand -template strand- grows in direction 3´ to 5´.  

Whenever we have a DNI molecule and we need to determine which strand is the coding one, we just need to look for the presence/absence of start or stop codons.

So, in the exposed example we have two strands, but we do not know yet which one is the coding one.

Conventionally, the first strand is always the coding one. However, let us analyze it by using the presence/absence of codons.

First-strand:

3’-ACGGATCCTCCCTAGTGCGTAATACG-5’

let us write it is 5´to 3´direction

5´- GCATAATGCGTGATCCCTAGGCA -3´

now let us identify the start and stop codons in 5´⇒3´direction.

Start codon ⇒ ATGStop codon ⇒ TAA, TAG, TGA

5´- GCATAATGCGTGATCCCTAGGCA -3´ ⇒ 1 start codon at the beginning

5´- GCATAATGCGTGATCCCTAGGCA -3´ ⇒ 3 Stop codons

Second strand: We will do exactly the same procedure

5’-TGCCTAGGAGGGATCACGCATTATGC-3’⇒ 1 start codon near the end

5’-TGCCTAGGAGGGATCACGCATTATGC-3’⇒ 1 stop codon at the beginning

What we did here was to identify in both provided strands, where the start and stop codons are placed. We can see that in the first strand we have the start codon near the beginning, while in the second strand we have it near the end of the sequence. From this information, we can assume that the first strand is the coding one. However, you need to know that some coding sequences do not have start and stop sequences, because they might correspond to a sequence in the middle of a gene.

So, the sequence of the DNA coding strand with a 5-3 polarity is

5´- GCATAATGCGTGATCCCTAGGCA -3´

The Gram stain provides a lot of clinically useful information but it won’t give you all the information you need for identification and treatment. About which of these do you NOT learn anything from the Gram stain?

Answers

Answer: d) The ability of the bacteria to process nutrients.

Explanation:

Incomplete question.

Options,

a) Structure of the cell wall b) Bacterial morphology c) Susceptibility to antimicrobial drugs d) The ability of the bacteria to process nutrients.

Gram staining is a type of differential staining to study bacteria, and is used to see cell morphology and to differentiate between gram-positive bacteria that appear violet and gram-negative bacteria that appear pink or red.

To perform the staining, fix the samples with methanol for one minute or heat and add a dye called crystal violet and wait one minute. Then rinse with water and add lugol for one minute. Then add acetone alcohol for 5-30 seconds. At this point, gram-negative bacteria discolor while gram-positive bacteria do not. After this, a contrast staining is performed by adding safranin or basic fuchsin for one minute. This stain will turn the gram-negative bacteria pinkish-reddish.

Crystal violet is a cationic dye that penetrates all bacteria through the bacterial wall. Lugol is a compound consisting of iodine and potassium iodide and acts as a mordant. The iodine enters the bacteria and forms an insoluble complex with the crystal violet, causing the crystal violet to bind more strongly to the bacterial cell wall. The added alcohol and acetone are used for decolorization, since the iodine/violet crystal complex is soluble in the alcohol and acetone. Thus, gram-positive bacteria do not decolorize, while gram-negative bacteria do.

A contrast stain such as safranin or fuchsin is used to highlight gram-negative cells. After contrast staining, gram-negative cells are pink or red, while gram-positive cells remain purple.

The wall of gram-positive bacteria consists of about forty layers of peptidoglycan which does not allow alcohol to pass through it because it is very thick, while that of gram-negative bacteria consists of a single layer of peptidoglycan. These differences cause gram-positive bacteria to retain the violet color and gram-negative bacteria to discolor.

So, with this type of staining we can certainly see the structure of the cell wall, because those that retain the violet dye even after treatment with a decolorant are gram-positive (many layers of peptodoglycan) and those that easily lose the first dye and take up the second are gram-negative (single layer). It also gives us an idea of the shape and morphology, which when stained will be visible under the microscope.

It also informs us about susceptibility to antibiotics, since some act only on gram-positive bacteria and others only on gram-negative bacteria. For example, gram-positive bacteria are sensitive to beta lactamase/penicillinase and gram-negative bacteria are susceptible to broad-spectrum penicillins such as piperacillin. However, this type of staining will not tell us about the bacteria's ability to process nutrients, because that is not a process related to the structure of the cell wall.

A muscle that is stimulated so frequently that the relaxation phase is eliminated is said to exhibit _______. Question 13 options: tetanus recruitment treppe wave summation

Answers

Answer:

tetanus

Explanation:

Tetanus causes a strong tonic contraction in skeletal muscles. This triggers a series of intermittent, progressive, and extremely painful muscle spasms. Tetanus is presented by patients who have stimulated a muscle too often, without allowing a moment of rest.

The extinction vortex represents the idea that even if an organism is extant, it may have a gene pool that will not support its long-term survival.A. TrueB. False

Answers

Answer:

True.

Explanation:

Extinction vortex is a model used by scientists to understand extinction dynamics within a community. This model allows scientists to assess and understand how a population can become highly vulnerable to elements of its habitat, becoming increasingly apt for extinction. According to this model, any organism is capable of extinction, as all are susceptible to having a gene pool that will not allow its survival, regardless of the environment.

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