Answer:
According to National Geographic, ostriches are a part of a very small group of birds that cannot fly because unlike most birds, their small wings are not strong enough to carry their body for flight and their breastbone isn't balanced enough for flying. Birds that are unable to fly are called ratites.
A number of scientists namely Thomas Huxley, Richard Owen, and others have tried to show that these ratites are actually related to each other and eventually, it was discovered that they all had one thing in common, the way the bones at the roof of the mouth were arranged was similar to that of reptiles rather than other birds.
Richard Owen found and assembled the remains of an extinct ostrich skeleton which was an extinct moa and contrary to already held opinion, one ratite known as tinamous did not really fit with the profile of a ratite because it could fly, even though almost grudgingly and they possessed keeled sternum which suggests that they evolved from flying birds.
DNA tests showed that tinamous evolved within ratites and not necessarily as a separate entity. The tests also showed that moas and tinamous are related.
It was also speculated that the division of the supercontinent Pangaea southern side led to the separation of flightless ratite ancestors, causing each landlocked group to evolve and become the flightless birds we know today such as the ostrich, rheas, etc.
Answer:
An ostrich is an extremely large bird that lives in Africa. It can’t fly, but it has powerful legs that allow it to outrun most predators. Its flexible knees and two-toed feet enable it to run easily. An ostrich has strong leg muscles that it can use to kick large predators. It has claws on its wings to defend itself from predators and thick feathers to keep it warm at night. Ostriches have thick eyelids that protect their eyes from sandstorms.
Explanation:
RNA polymerase is an enzyme that copies (1 point)
o DNA into DNA.
O RNA into mRNA
O mRNA into tRNA.
DNA into RNA
Answer:Copies DNA into RNA
Explanation:
Design a controlled experiment to test the effect of water temperature on goldfish. be sure to include your hypothesis, independent variable, dependent variable as well as experimental group and control group.
Answer:
In this experiment, indepedent variable will be temperature and dependent variable will be the respiratory rate of goldfish. Temperature affects the respiratory rate of goldfish, as it's respiratory rate decreases with decrease in temperature of water, the experiment is as follows:
Take two glass containers filled with water A and B and put one goldfish in each container.Measure the temperature of the water using a thermometer.Count mouth movement of both the fishes in certain time.Now put some ice in container B that will decrease the temperature of water and measure the temperature again.Now count the mouth movement of both the fishes for the same time it was counted earlier.The result will be that respiratory rate of goldfish decreases with the decrease in temperature in container B in comparison to container A goldfish.
An experiment meant to determine the cause of an effect, the effect is the independent variable, while the cause is the dependent variable
A controlled experiment to test the effect of water temperature on goldfish is designed as follows:
The experimental group are: The gold fish in a glass Jar X filled with fresh water and with the lid left open (the treatment of temperature reduction is applied to the experimental group)
The control group are: A second gold fish (selected at random) of the same size, in another glass jar Y filled to the same level with fresh water collected from the same source of the first gold fish
Independent variable: The independent variable is the temperature of the water which will be varied by placing ice cube gradually into the glass jar B
Dependent variable: The number times the gold fish gulp air by rising to the surface, and or the number of time goldfish opens its mouth, which indicates that the goldfish is breathing
The hypothesis: The breath rate of goldfish decreases with decrease in temperature because the goldfish metabolic rate decreases and the water holds more dissolved air and therefore oxygen at a reduced temperature
The Experiment Design:
The experiment is conducted by measuring the initial temperature and breathing rate of both fishes
The temperature of the fresh water in jar X is decreased gradually by adding ice cubes and recording the temperature and breathing rate of the goldfish
A similar experiment from an online source (Maryland School improvement website) the following results where obtained
[tex]\begin{array}{|c|cc|} \underline {Breathing \ rate}&&\underline {Water \ Temperature } \\&&\\ (Dependent \ Variable)&&(Independent \ Variable)\ \\&&\\103&&78.8 ^{\circ}F\\78&&68^{\circ}F\\55&&57.2^{\circ}F\\28&&46.4^{\circ}F\\4&&35.6^{\circ}F\end{array}\right][/tex]
From the experiment, it can be seen that the in the experimental group dependent variable, which is the breathing rate of the goldfish reduces as the temperature which is the dependent variable is reduced
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A decrease in muscular activity or damage to neurons that attach to skeletal muscle can lead to a reduction in the size of muscle called
Answer:
The correct answer is atrophy
Which location is least likely to experience a volcanic eruption? Α. an island hot spot, such as the island of Hawaii B. Hamilton County on the plains of central Texas с. a convergent boundary, as in the Ring of Fire D a volcanic island arc, such as the Aleutian Arc in Alaska
Answer:
i think that the answer is B. Hamilton County on the plains of central Texas i took the test
Explanation:
Hamilton County on the plains of central Texas is least likely to experience a volcanic eruption. Therefore, option (B) is correct.
What are volcanoes?Molten rock and gases stored under the surface erupt through a volcano, generating a hill or mountain.
Active, inactive, or extinct volcanoes. Active volcanoes are likely to erupt again. Dormant volcanoes may erupt again. Extinct volcanoes won't erupt.Magma collects inside active volcanoes. The magma chamber's pressure forces it through rock channels and onto the planet's surface.
Volcanic eruptions can be violent or slow-moving. Volcanoes erupt through vents on the sides or a primary entrance at the top. The volcano's morphology depends on eruption rate and magma chemistry. Land and sea volcanoes exist. As lava cools and hardens, underwater volcanoes build mountains and ranges. When volcanoes rise above the ocean, they create islands.
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identify the components ( parts) of DNA
Answer:
Phosphorus group, a sugar(like deoxyribose or ribose), and a nitrogenous base
In the image, the arrow Is pointing to a celestial object. Which attribute disqualifies the object from being a planet?
A. It appears to have no moons.
B. It is spherical in shape.
C. Its neighborhood is not clear.
D. It has horizontal bands on its surface.
The correct answer is C. Its neighborhood is not clear.
Explanation:
One of the key features of a planet is that it clears its neighborhood; this means the planet gravitational force is strong enough that there are no other celestial bodies on its orbit or next to it except by its moons or satellites. This does not occur in the image presented because there are smaller celestial bodies near to the main or bigger celestial body. This likely occurs if the celestial body is not big enough to clear its neighborhood, and therefore it is not a planet.
ABO blood type is examined in a Taiwanese population, and allele frequencies are determined. In the population,
f (IA) = 0.30,
f(IB) = 0.15, and
f (i) = 0.55.
What are the frequencies of the various genotypes and various phenotypes in this population? Assume Hardy-Weinberg equilibrium.
Answer and Explanation:
Due to technical problems, you will find the answer and explanation in the attached file.
A.While the traits studied in Exercise 1 were hypothetical genetic traits, what type of genetic traits do you think are important to study and predict
Answer:
Genetic disturbances harmful to the organism are genetic characteristics that must be studied and predicted.
Explanation:
Genetic disorders that harm an organism such as sickle cell anemia, hemophilia, Turner syndrome, among others, are important to be studied and predicted, because it will provide better maintenance of that organism. Allowing people who inherit these characteristics to have more efficient treatments and a better life, since the prediction of these characteristics allows the family to establish better adapapitativo methods, that will make the life of this individual easier and with more quality.
PLEASE ANSWER QUICK!The Greek roots of the word prokaryote mean “before nucleus.” Describe the way that DNA is organized in prokaryotic cells without the help of a nucleus. How does this approach differ from the way that eukaryotic cells organizes their DNA
Answer:
Prokaryotic cells' DNA are located in the cytoplasm of the cell rather than in the nucleus, like in eukaryotic cells. DNA aids in protein synthesis and determines functions of the cell in cells, regardless of being within the membrane of a nucleus or not.
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I hope this helps a little.
The word prokaryote in Greek means before kernel (nucleus). Unlike the eukaryotic cells, the nuclear material is located in the cytoplasm of the cell in a nucleoid.
What are the characteristics of prokaryotic cells?The prokaryotic cells are the primitive karyons that are defined by the lack of the true nucleus and organelles. Unlike the eukaryotes, the organelles lack the membrane that covers them but has a tough cell wall.
The prokaryotes include archaea and bacteria which are unicellular and microscopic organisms that are simple and have their genetic material organized into nucleoids in the center of the cell. They have the ability to live in harsh conditions.
Therefore, the eukaryotes and prokaryotes differ in the arrangement of the genetic material.
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____________ a regulatory protein that may bind DNA to inhibit transcription. ____________ a DNA sequence that binds a regulatory protein. ____________a DNA sequence that binds RNA polymerase and regulates transcription. ____________a compound that interacts with another protein or compound to form an active repressor ____________a compound that induces or activates transcription, such as lactose.a. Repressorb. Operator c. Promoterd. Corepressore. Inducer
Answer:
A repressor is a regulatory protein that may bind DNA to inhibit transcription. An operator is a DNA sequence that binds a regulatory protein. A promoter is a DNA sequence that binds RNA polymerase and regulates transcription. A corepressor is a compound that interacts with another protein or compound to form an active repressor. An inducer is a compound that induces or activates transcription, such as lactose.
Explanation:
Repressor proteins bind to DNA and RNA to suppress target gene expression. A DNA repressor blocks transcription by inhibiting the attachment of RNA polymerase to the promoter sequence, while an RNA repressor bind to the mRNA to block translation of the protein. An operator is a DNA sequence required for the attachment of transcription factors. The genes that are transcribed by the binding of a transcription factor to an operator sequence are collectively referred to as an operon. Operons are generally found in prokaryotes but they also can be found in some eukaryotes including Caenorhabditis elegans and Drosophila melanogaster. An inducer is a molecule that activates gene transcription either by binding to repressors/corepressors (thereby inactivating their functions) or by binding activators. For example, the allolactose act as an inducer of the lac operon.
Knowledge of the driver mutations underlying cancer has led to targeted therapeutics, such as the protein kinase inhibitor imatinib (trade name Gleevec) in cases of chronic myeloid leukemia. Cancer cells often become resistant to a given drug, so researchers continue searching for new drugs that target proteins that contribute to the cancerous phenotype. One recent promising approach uses drugs that lead to ubiquitination and proteasomal degradation of the target protein. Which of the following mutated proteins are good candidates for this approach?
A) oncogenes
B) proteins with loss-of-function mutations
C) proteins with gain-of-function mutations
D) tumor suppressor genes
Answer:
C) proteins with gain-of-function mutations
Explanation:
Gain-of-function mutations: In biology, the term "gain-of-function mutation" is described as one of the different types of mutation in which the altered or changed "gene product" consists of an entirely new pattern or molecular function associated with gene expression. However, the "gene-of-function mutations" are being always considered as "Semidominant or Dominant".
In the question above, the correct answer is option C.
Every interaction with the outside world is because of A) epithelial tissue B) connective tissue C) nervous tissue D) muscular tissue
Answer:
A cutaneous membrane is a multi-layered membrane composed of epithelial and connective tissues. The apical surface of this membrane exposed to the external environment and is covered with dead, keratinized cells that help protect the body from desiccation and pathogens....
why are g protein important for drug discovery?
Answer:
G protein - coupled receptors(GPCRs)n belong to a large family of signaling proteins that mediate cellular reponses to most hormones ,metabolites,cytokines and neuotransmitters and therefore serve as fritful targets for DRUGS DISCOVERYS.
Explanation: histamine(HRH1),serotonin dopamine,opiod and adrenergic receptors.
I HOPE IT'S HELPS YOU TO UNDERSTAND
A mutation that hides the effect of another mutation at a site that is distinct from the site of the original mutation, but with in the same gene. This mutation is best described as a
Answer:
The correct answer is intragenic suppressor mutation.
Explanation:
A suppressor mutation partially or completely converses the effects of a different mutation. A suppressor mutation is of two kinds, that is, an intragenic suppressor and an intergenic suppressor. An intragenic suppressor converses the influence of a mutation at a distinct site in a similar gene.
On the other hand, an intergenic suppressor converses the influence of a mutation at a distinct locus of the gene. It is the intragenic suppressor mutation, which takes place in a similar gene where the occurrence of the first mutation had taken place. Therefore, the mutation, which hides the influence of another mutation at a location, which is different from the location of the original mutation, but taking place in a similar gene can be illustrated as the intragenic suppressor mutation.
The diagram represents a food pyramid. The concentration of the pesticide DDT in individual
organisms at level D is higher than the concentration in individuals at level A because DDT is
A. produced by organisms at level C ingested by
those in level D
B. passed through levels A, B, and C to organisms
at level D.
C. excreted by organisms at level A as a toxic
waste.
D. synthesized by organisms at level D.
Answer:
The answer is "Choice b".
Explanation:
In the given question diagram is missing. so first, we define the diagram after that we explain why the above given choice is correct.
In the attached file the food pyramid can be a divide into the level, in which the D pesticides use the "dichloro-diphenyl-trichloroethane ", which concentration is higher than its entities from the level of A because DDT is transferred with species at level D by levels A, B, and C, that's why the choice "b" is correct.
Circle
1
2
Circle the most reactive metal in each set.
1) Magnesium / Potassium
2) Aluminum / Gold
3) Cobalt / Cesium / Calcium
4) Iron / Titanium / Potassium
5) Francium / Lithium / Beryllium
لی
Answer:
Explanation:
1) potassium
2)Aluminium
3) Cesium
4) potassium
5) Beryllium
(06.03 LC) Which of the following is an example of how HIV can be transmitted from one person to another? Contact between infected blood and a mucus membrane Contact between infected saliva and an open wound Contact between infected blood and skin Contact between infected saliva and lining of mouth
Answer:
i believe the answer is contact between a infected blood and a mucus membrane
Explanation:
What complications might arise from genetic screens targeting an organ that differentiates late in development?
Answer:
No sign of testicular development in boys and breast development in girls.
Explanation:
Complications like no sign of testicular development in boys and breast development in girls occurs if an organ develop very late. There are many causes of this type of complications such as long term illness, eating improper food and disorder of sexual development. Sometime these complications also occurs due to genetically. These complications should be treated well with medication and use of nutritious food. These medicines increases the performance of sex hormones in order to initiate puberty.
Is the talc renewable?
Answer:
no.its nonrenewable.
talc is nonrenewable.
thanks.
When the body cells are hypotonic to the blood plasma, water will move from intracellular fluid to extracellular fluid.
A. True
B. False
Answer:
True
Explanation:
Which sentence about protist is accurate
Answer:
there are no sentences
Explanation:
QUICKLY! The chemical reaction equation of photosyntesis is shown here: What information is not given in this equation. It does not show if the reaction is reversible. It does not show the reactants needed for the reaction. It does not show that photosynthesis consists of many separate steps. It does not show the number of molecules required to produce glucose.
Answer:
C: It does not show that photosynthesis consists of many separate steps.
Explanation:
Photosynthesis is a unique process carried out by the cells of autotrophic organisms. It is the process whereby they synthesize their own food in form of sugars (glucose) in the presence of sunlight. Ideally, the photosynthetic process makes use of carbon dioxide (C02) and water (H20) in the presence of light energy (from sun) to produce glucose sugar (C6H12O6) and oxygen (02). The general photosynthetic equation is as follows:
6CO2 + 6H20 + light → C6H12O6 + 6O2
However, the process is not as simple as portrayed as it involves many separate steps that collectively forms the photosynthetic product (glucose). Photosynthesis occurs in two major stages namely: light stage and light independent stage, which in turn consists of series of reactions that forms the products.
Therefore, the equation attached to this question describes photosynthesis but It does not show that photosynthesis consists of many separate steps.
Answer:
C: It does not show that photosynthesis consists of many separate steps.
Explanation:
The main function of a cell membrane is to allow substances to enter and leave the cell. Which is a correct description of transport through a cell membrane
Answer:
The question is incomplete, below is the completed question:
The main function of a cell membrane is to allow substances to enter and leave the cell. Which is a correct description of transport through a cell membrane ?
a. Diffusion, or passive transport, occurs when molecules diffuse from a lower concentration to a higher concentration.
b. Facilitated transport occurs when proteins that extend through the cell membrane provide a channel through which certain substances can diffuse more rapidly than by passive diffusion.
c. The lipid bilayer opens up and allows the ions or molecules to enter the cell, then closes.
d. Active transport occurs when molecules diffuse from a higher concentration to a lower concentration.
Answer:
b. Facilitated transport occurs when proteins that extend through the cell membrane provide a channel through which certain substances can diffuse more rapidly than by passive diffusion.
Explanation:
Transport through cell membranes can be broadly classified as active transport or passive transport.
Active transport requires energy in the form of ATP for the transportation of substances across the cell membrane.
Option b correctly describes facilitated diffusion, which is a passive-mediated diffusion process, where channels in the cell membrane mainly composed of proteins called transmembrane integral proteins, allow for the movement of certain molecules (mostly polar/hydrophilic) molecules that will not otherwise be transported through simple diffusion because of the hydrophobic nature of the cell membrane.
The other options are wrong because:
a. diffusion or simple transport involves the movement of substances from regions of higher to a lower concentration not lower to higher as suggested here.
c. The lipid bi-layer does not allow ions or hydrophilic molecules because it is hydrophobic in nature, and it is not a channel, so it does not open and closes
d. In active transport, transfer of molecules is from regions of lower to higher concentration and not higher to lower concentration as suggested here.
assuming hardy weinberg equilibrium what is the probability that sarah who is phenotypically normal with no family history and tom
Answer:
The probability of having a disorder is 50 %.
Explanation:
The offspring has that genetic disorder if the Sarah who is phenotypically normal with no family history and tom has a genetic disorder so there is 50 percent chance that the children of Sarah and tom has that genetic disorder. if the disorder linked with Y chromosome of male so this disorder is present in the sons but if the disorder linked with X chromosome of male so this disorder is present in the daughters.
Which type of nuclear power reactor is used in only 1 percent of all power plants?
Answer:
Breeder reactors
Explanation:
The type of nuclear power reactor that is used in only 1 percent of all power plants would be Breeder reactors.
What percentage of the nation’s demand for electricity could be produced in the future by wind energy?
Answer:
5-10%
hope this is helpful
What makes up the backbone of a DNA molecule? nucleic acids RNA molecules sugars and phosphates ribose and deoxyribose
Answer:
sugars and phosphates
Explanation:
gradpoint
What physical traits were favored in the peppered moth AFTER the Industrial Revolution?
Answer: Their skin color was dark which made the moths blend in. During the Industrial Revolution, the soot from factories caused the trees to become black. The light colored moths became easier to kill because they could not blend into their environment.
Explanation:
Why are G proteins known as guanine nucleotide-binding protein?
Answer:
G proteins, also known as guanine nucleotide-binding proteins, are a family of proteins that act as molecular switches inside cells, and are involved in transmitting signals from a variety of stimuli outside a cell to its interior. ... G proteins belong to the larger group of enzymes called GTPases.
Use the following scenario to answer the next following question(s):
You and your friends go to the beach for vacation. You all walk down to the beach to go swimming. When you get there, you see the water is murky and green, and there are algae blooms floating on top.
Reference: Ref 6-3
If it is excess nutrients which are feeding the algae blooms and lowering the oxygen content in the water, that process is called:
A. nutrient cycling.
B. nitrification.
C. eutrophication.
D. hypoxia.
Answer:
eutrophication
Explanation:
Eutrophication refers to a situation in which the aquatic environment becomes excessively enriched with nutrients. This leads to algal blooms in aquatic habitats such as lakes. These nutrients come from Fertilisers used in farming, which find their way into water bodies through run-off thereby increasing nutrient levels.
Excess nutrients causes phytoplankton to grow and reproduce at an alarming rate resulting in algal blooms. This bloom disrupts the balance in the ecosystem leading to many problems.
The algae may end up using all the oxygen in the water, causing oxygen shortage for aquatic life. Some of the algae may die, their decay may lead to further oxygen depletion. As oxygen is depleted, aquatic organisms may also begin to die.
