Answer:
B. Crossover formation is a necessary step in meiosis I to ensure proper chromosome segregation
Explanation:
Crossing-over is a unique phenomenon that occurs in the prophase I stage of meiosis I, where non-sister chromatids of homologous chromosomes exchange their chromosomal segment. The physical point where this exchange occurs is called CHIASMATA. Hence, a mutation that affects the gene associated with the chiasmata will affect the occurrence of crossing over or homologous recombination.
Crossing-over, through the formation of the chiasmata, is responsible for the physical alignment and proper segregation of chromosomes into gametes. Naturally, the chiasmata formed as a result of recombination during meiosis helps ensure that the chromosomes stay together until it is the right time to separate. This way, any chromosomal defect in the resulting gamete is prevented.
However, an error or defect in homologous recombination might give rise to gametes with chromosomal disorder, a condition known as ANEUPLOIDY i.e. missing or additional chromosomes in gametes. This can affect the fertility of the involved human.
is the basic unit of structure and function of living things.
Answer:
cells
Explanation:
is the basic unit of life :)
1. A star is 520 light years from Earth. During what event in history did the
light now arriving at Earth leave the star?
Answer:
A light year is the distance which is equal to 9,460,730,472,580.8 km, so:
= 4.91957985 X [tex]10^{15}[/tex]km
which is distance travels by the light. Now what time it takes light to travel distance we found.
A year has 365.25 days, so,
[tex]1 (\frac{365.25)}{1 year}) (\frac{24}{1 day}) (\frac{3600 s}{1 hr} )[/tex] = 31557600 seg/year
The light speed in the space is equal to 299,792.458 km/s, so:
4.91957985 x [tex]10^{15} (\frac{1 seg}{29792.458}) \frac{1 year}{31557600}[/tex] = 520 years
if today, August, 2020, then
2020 - 520 = 1500
Spanish and Portuguese spread out over the southern part of the Western Hemisphere and bring in America brought to Spanish colony of Santo Domingo in year 1500.
[tex]t=2019-520\\ t=1499 AD[/tex]
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I need help with this
Answer:
I know the answer
Explanation:
Yes
Yes
Yes
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.
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.
(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:
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.
Drag each tile to the correct location.
Sort the descriptions based on whether they are related to asexual reproduction or sexual reproduction.
creates genetically
unique offspring
creates genetically
identical offspring
organism doesn’t have to
waste energy to find a
mate
organism needs time to
reach adulthood to
reproduce
requires the contribution
of two parents
requires the contribution
of a single parent
Answer:
SEXUAL REPRODUCTION:
-creates genetically unique offspring
-organism needs time to reach adulthood to reproduce
-requires the contribution of two parents
ASEXUAL REPRODUCTION:
-creates genetically identical offspring
-organism doesn’t have to waste energy to find a mate
-requires the contribution of a single parent
Explanation:
Living organisms employ two types of reproduction to produce their offsprings. They are sexual reproduction and asexual reproduction.
Sexual reproduction is that reproduction involving the fusion of two sex cells from opposite sex individuals i.e. male and female. Sexual reproduction forms offsprings with unique genetic contents, which is as result of the meiotic process that each individual organism undergoes to produce gametes or sex cells (sperm and eggs). Since there must be a fusion of gametic cells, sexual reproduction requires the contribution of two parents (a male and a female). Also, the parents only undergo meiosis to produce gametes at certain points in their life. Hence, they have to wait to reach adulthood to do that.
On the other hand, asexual reproduction involves only the contribution of one parent as the fusion of genetic material is not needed. Hence, the offsprings form by cellular division that makes it genetically identical to the parent cell. Energy is not needed to find a mate, the organism simply reproduces on its own by dividing into daughter cells.
n your lab you are studying the genome of venomous rattlesnakes to find the gene which codes for their venom glands. You have two rattlesnakes, one rattlesnake has a mutation but can still produce venom. You compare his DNA to a normal rattlesnake. What type of mutation has occurred? Normal: AATCGCTACGCACGTCAG Mutated: TATCGCTACGCACGTCAG
Answer:
There are no options but the kind of mutation that occurred by carefully observing both sequences is:
POINT SUBSTITUTION MUTATION
Explanation:
Mutation is any change, whether small or big, in the nucleotide sequence of a gene (DNA). Mutation occurs from time to time in an organism either by a mistake during DNA replication or induced by a mutagen (mutation-causing substance). Mutation can be of different types depending on the effect on the mutant.
In this case of comparing the DNA sequence two rattle snakes, the sequences of the two snakes are:
Normal: AATCGCTACGCACGTCAG
Mutated: TATCGCTACGCACGTCAG
By carefully observing the two DNA sequences, one would realize that the only difference in the two sequences is the first nucleotide base. That is, in the normal sequence, th first base is Adenine (A) while in the mutated sequence, the first base is Thymine (T).
This type of mutation that involves only one nucleotide base is called POINT MUTATION. It can also be noticed that base "A" was changed "T". Hence, this is a type of SUBSTITUTION MUTATION because a single base was replaced by another in the sequence.
identify the components ( parts) of DNA
Answer:
Phosphorus group, a sugar(like deoxyribose or ribose), and a nitrogenous base
what type of molecule do plant cells use for long term energy storage
Answer:
ATP
Explanation:
In plants, energy is stored in the form of ATP and NADPH. Energy is produced in the presence of light it is in the thylakoids and mitochondria.
ATP: Adenosine triphosphate
NADPH: nicotinamide adenine dinucleotide phosphate hydrogen
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.
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.
If tall is dominant over short, and yellow seed is dominant over green, how would you write the genotype of a pea plant that is heterozygous for tall, and that produces yellow seeds
Answer:
The answer has been written in paper and the image of the paper has been attached. Feel free to raise any doubt.
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:
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:
The ostrich is a bird. However, it has traits that are different from those of the birds we typically see flying around our neighborhoods. Using credible sources, investigate the environment and adaptations of ostriches to explain how they evolved to survive in their environment.
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:
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.
contrast primary growth and secondary growth
Answer:
There are contrast of the Primary growth and Secondary growth in many ways.
Explanation:
The Primary growth is to increase the length of that shoot and the root is referred to the primary growth.The primary growth act the way as shoot apical causing extension to the growth system into the root and ground they root are apical.The primary growth is the plant into that ground to contain water and nutrients that with the soil relation.The primary growth is that root can take different forms depends on the plant is Mono cot,the primary root replace by the stem after the plant germinates its called Adventitious root.The secondary growth is that performed to increase by the girth of the plant.Secondary growth is to produce the lateral cambiums that layer of tissue add to the plant growth.Secondary growth is that performed and support from the shoot system into the transporting that water and nutrients.Secondary growth is to provide the cross section of the stem and the replace with newer layer, the layer of that growth bark.Secondary growth is to consist that bark remain that the narrow of band, it root is transformed.Aquatic organisms in coastal areas face a variety of predators on land and in the water and air. Which ocean process exposes the coastal aquatic organisms to land-based predators? a. Changing wind patterns alter the ocean currents, changing tide levels. b. Daily tidal patterns leave areas exposed to the land for part of the day. c. The constant wave action generates nutrients that attract predators. d. The ocean conveyor belt raises and lowers the water levels on the coasts.
Answer:
b
Explanation:
The correct answer as to the ocean process that exposes the coastal organisms to land-based predators would be the daily tidal patterns that leave the coastal area exposed to the land for a part of the day.
Some parts of the coastal areas become exposed to land during certain periods of the day as a result of tidal waves. When this happens, the aquatic organisms occupying these coastal areas become temporarily exposed to land predators who hunt and kill them for food.
Therefore, the correct option is b.
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
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
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 sentence about protist is accurate
Answer:
there are no sentences
Explanation:
During cellular movement which filaments will be the ones that are responsible for attaching and pulling the other filaments along?
Answer:
Myosin
Explanation:
Myosin are the major components of both muscle and non muscle cells in striated muscles which is responsible for contraction or movement that convert chemical energy (ATP) into mechanical work thereby generating force and movement.
During cellular movement , myosin filament will be the ones that are responsible for attaching and pulling the other filaments along because Myosin binds to actin at a binding site on the globular actin protein,it also have ATP binding sites which hydrolyses ADP to ATP , ATP binding causes myosin to release actin, which make actin and myosin to detach from each other thereby causing attachment and contraction of other filaments
Following antigenic stimulation, phosphorylation of _________ relieves inhibition of the transcription factor
Answer: zap70, ITAM.
Explanation:
An antigen is any substance that is capable of stimulating an immune response by activating lymphocytes, which are the body’s infection-fighting white blood cells. Examples of antigens could be proteins that are part of bacteria or viruses or components of serum and red blood cells from other individuals, all of them are foreign antigens originated outside the body. However, there can also be autoantigens (which are self-antigens), originated within the body. In normal conditions, the body is able to distinguish self from nonself. And the antigens that represent a danger induces an immune response by stimulating the lymphocytes to produce antibody or to attack the antigen directly. This is called an antigenic stimulation of the immune system.
ZAP-70 (Zeta-chain-associated protein kinase 70) is a protein that is part of the T cell receptor, thereby it plays a critical role in T-cell signaling. When the TCR (receptor of T cells) is activated by the presentation of the specific antigen through the MHC, a protein called Lck acts to phosphorylate the intracellular CD3 chains and the ζ chains of the TCR complex, allowing the binding of the cytoplasmic tyrosine kinase, ZAP-70. Lck then phosphorylates and activates ZAP-70, which in turn phosphorylates another molecule in the signaling cascade called LAT (short for Linker of Activated T cells), a transmembrane protein that serves as an anchor site for several other proteins. The tyrosine phosphorylation cascade initiated by the Lck culminates in the intracellular mobilization of calcium ion (Ca2+) and the activation of important signaling cascades within the lymphocytes. These include the Ras-MEK-ERK pathway, which is based on activating certain transcription factors such as NFAT, NFκB and AP-1. These transcription factors regulate the production of of certain gene products, most notably cytokines such as interleukin-2 that promote the long-term proliferation and differentiation of activated lymphocytes.
The ITAM motifs (immunoreceptor tyrosine-based activation motif) are sequences of four amino acids present in the intracellular tails of certain proteins that serve as receptors within the immune system. Thus, some receptors such as the TCR have ITAM sequences that, when activated, trigger an intracellular reaction based on consecutive phosphorylations. Kinases are recruited for this purpose.
So, ZAP-70 is a protein tyrosine kinase with a role in T-cell receptor signal transduction. During T-cell activation, ZAP-70 binds to ITAM and becomes tyrosine phosphorylated. The binding of ZAP-70 to the phosphorylated ITAM is able to activate its kinase activity, and relieves the inhibition of the transcription factor which regulates genes that are involved in the immune reaction.
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.
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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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:
____________ 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.
