Answer:
an adaptation can be defined as an inherited trait which confers an evolutionary advantage to the organism in a certain environment
Explanation:
An adaptation, also known as an evolutionary adaptation, can be defined as any physiological and/or morphological inherited trait related to the improved evolutionary fitness of one organism in a particular environment. An adaptation improves the chances of survival and reproduction in a certain environment, thereby organisms carrying the adaptation have more chances to produce descendants and pass their genes to the next generation. Some classical examples of evolutionary adaptations include the long necks of giraffes that help them to eat leaves at the top of trees, light bones of flying birds, etc.
Compare the effect of acetylcholine on cardiac muscle with its effect on skeletal muscle. Can you explain the mechanistic basis for the difference
Answer:
The action of the neurotransmitter acetylcholine, released by the vagus nerve in the heart, slows the heart rate and weakens the force of contraction. The skeletal muscle has the ability to perceive a stimulus and respond to it. As regards skeletal muscles, the stimulus is chemical in nature: acetylcholine released by the motor nerve ending. The response of the muscle fiber is the production and propagation along its membrane of an electrical current (action potential) that causes muscle contraction.
Explanation:
Acetylcholine is one of the most abundant neurotransmitters in the central and peripheral nervous system. Acetylcholine receptors are nicotinic (ionotropic) and muscarinic (metabotropic GPCR). In skeletal muscle of adults, acetylcholine binds to the alpha subunit of the nicotinic channel, which are two of the five subunits that make up the pore of this channel. Acetylcholine released by the nerve ending binds to the receptor in the sarcolemma and triggers an electrical current - the action potential. This spreads along the sarcolemma and causes a signal to pass from the T tubule to the sarcoplasmic reticulum in the triad, which then releases calcium ions (Ca ++). Once the calcium ions are released, by diffusing between the actin and myosin protein filaments, they cause the myofibrils to contract. On the other hand, in cardiac and smooth muscle cells, acetylcholine binds to 7M proteins, which do not function as channels, but are typical members of the GPCR class A superfamily. One of the physiological mechanisms of acetylcholine is the regulation of the heart rate, through the mobilization limited to the inner face of the plasma membrane of the dimer bg of protein G. This dimer transduces the specific binding of the ligand with its receptor in the plane of the membrane, thanks to its proximity with the ion channel or with enzymes bound to the plasma membrane. This can be done because its g subunit remains attached to the inner face of the membrane.
Which of the following correctly explains the differences between artificial and natural selection?
Not sure what the options are, but artificial selection would be when farmers/breeders choose only to plant/breed the organism with desired characteristics in order to cause the evolution of the trait while natural selection is when organisms that are better adapted to their environment usually survive and produce offspring, causing the evolution of their traits which help them to survive.
Hope that helps!
Genes for body color (B black dominant to b yellow) and wing shape (C straight dominant to c curved) are located on the same chromosome in flies. If single mutants for each of these traits are crossed (i.e. a yellow fly crossed to a curved-wing fly), and their progeny is testcrossed, the following phenotypic ratios are observed among their progeny.
Black, straight 17
yellow, curved 12
black, curved 337
yellow, straight 364
Required:
Calculate the map distance between B and C.
Answer:
Map distance = Genetic distance, GD = 3.9 MU ≅ 4 MU
Explanation:
The more separated two genes are, the more chances of recombination there will be. The closer they are, the fewer chances of recombination there will be. Two genes that are very close will have a few recombination events and are strongly bounded.
To analyze the recombination frequency, we have to know that:
1% of recombination = 1 map unit = 1centi Morgan = 1,000,000 base pairs. And that the maximum recombination frequency is always 50%.The map unit is the distance between the pair of genes for which every 100 meiotic products one of them results in a recombinant one.
Knowing that the genes are linked, we can calculate genetic distances between them. First, we need to identify the genotypes of the parental gametes with the ones of the recombinants. We can recognize the parental gametes in the descendants because their phenotypes are the most frequent, while the recombinants are the less frequent. So:
Parentals:
black, curved 337yellow, straight 364Recombinants:
Black, straight 17yellow, curved 12To calculate the recombination frequency we will make use of the next formula: P = Recombinant number / Total of individuals.
P = Recombinant number / Total of individuals.
P = 17 + 12 / 337 + 364 + 17 + 12
P = 29 / 730
P = 0.039
The genetic distance (GD) will result from multiplying that recombination frequency (P) by 100 and expressing it in map units (MU).
GD = P x 100
GD = 0.039 x 100
GD = 3.9 MU ≅ 4 MU
When we say that a bulb is fused, what is wrong with the bulb? How can we use it again?
Hey mate !
here is ur answer(refer the image)
thank u ..
hope it helps ... if so mark me as brainliest plz
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A helium atom that has only two electrons will have its electrons in which orbital(s)?
1s orbital
Explanation:
The electron has to go into the first energy level, in the 1s orbital. Helium, with two protons, will have two electrons. These are placed one at a time into the 1s orbital. This makes helium a very contented atom.
propose two ways the body temperature of a sick person can be brought to normal
Answer:
ice pack
Explanation:
Answer:
Swimming in cool water, taking a lukewarm bath, or applying cold water to the body can reduce body temperature.
Explanation:
hope this helps you!
which of the following is not a condition that must be made for hardy-weinberg equilibrium 1.no mutation 2.no migration 3.domunant alleles nore frequent than recessive allels 4.large population 5. no natural selection guy please answer this one
Answer:
3.dominant alleles more frequent than recessive alleles
Explanation:
To achieve hard-Weinberg equilibrium, certain conditions must be made.
These conditions are:
1. There is noo mutation,
2. Existence of random mating,
3. There should be no natural selection
4. There is the infinite population size
5. No migration
Hence, in this case, the correct answer is option 3, which is not a condition to be made for Hard-Weinberg equilibrium
Simple organisms usually make exact copies of themselves when they reproduce. What do we call this type of reproduction?
Answer:
asexual reproduction.
what was the speed of a car that traveled 240 m in 12 s
Answer:20
Explanation: Because when you divied 240 by 12 you get 20.
240/12=20
Answer:
20m/s
Explanation:
Speed is equal to distance/time. Since we know that the distance is 240m and the time taken to travel 240m was 12 seconds, we can divide them 240/12 and once we do this we can get our final answer of 20m/s.
1. Explain how the atomic number and mass number of an atom can be used to determine the number of
electrons and of neutrons respectively.
Because the total of neutron and proton/electron is the atomic mass. So if you wanna find proton/electron and you know the neutron, just minus the atomic number with the neutrom and you will get the proton
Here if you need the formula
Atomic number = Total neutron + Total proton or electron
help me woth these two ill give free BRAINLESS
answer : the elbow is an example of the second last one (it won't let me write the word)
Answer:
Answer D
Explanation:
This is a synovial joint, or just D
Decrease in blood pressure in directly causes widespread VASCONSTRICTION Resulting in a rise in blood pressure is this a negative or positive feedback ?
Will give brainliest
Which best describes how limiting factors affect all the species in this ecosystem?
Answer:
Its a COYOTE
Explanation:
which of the following is the most complex
according to their cellular level of organization? A.
Hair B. Euglena C. Hydra D.Heart. bplease give explanations.
d.corazon.ya que sin el no habria vida
Use the cladogram to answer the question. Which trait(s) does the salamander have?
Lancelet
(outgroup) Lamprey Tuna Salamander Turtle
Leopard
Hair
Amniotic e99
Four walking legs
Jaws
Vertebral column
amniotic edd and hair
vertebral column, jaws, and four walking legs
four walking legs only
vertebral column and jaws only
Answer:
everything plesiomorphic (ie ancestral) so 4 walking legs, jaws and vertebral column
Explanation:
A cell has two pairs of submetacentric chromosomes, which we will call chromosomes Ia, Ib, IIa, and IIb (chromosomes Ia and Ib are homologs, and chromosomes IIa and IIb are homologs). Allele M is located on the long arm of chromosome Ia, and allele m is located at the same position on chromosome Ib. Allele P is located on the short arm of chromosome Ia, and allele p is located at the same position on chromosome Ib. Allele R is located on chromosome IIa and allele r is located at the same position on chromosome Ib. Allele G is located on the long arm (q arm) of chromosome Ia, and allele g is located at the same position on chromosome Ib. Allele N is located on the q arm of chromosome IIa and allele n is located at the same position of chromosome IIb.
Required:
a. Draw these chromosomes, identifying genes R, r, G, g, N, and n as they might appear in metaphase I of meiosis. Assume there is no crossing over.
b. Taking independent assortment and the subsequent random separation of chromosomes in anaphase I, draw the chromosomes, with genes identified, present in all possible gametes that could result once this cell completes meiosis. As above, assume there is no crossing over. Explain in your own words what is meant by independent assortment.
Answer:
Note: You will find the chromosomes and the gametes in the attached files
Chromosomes:
IA ----------G-----о---------IB -----------g-----о----------IIA --------N--------------о------R----IIB ---------n--------------о-------r----Gametes:
Gamete 1: GNR Gamete 2: Gnr Gamete 3: gNRGamete 4: gnrIndependent assortment occurs when the alleles of two or more different genes distribute in the gametes independently from each other.
Explanation:
Available data:
two pairs of submetacentric chromosomes
IA -------------------о-----------
IB -------------------о-----------
IIA ----------- ------------о------------
IIB ------------------------о------------
chromosomes Ia and Ib are homologs
IA -------------------о-----------
IB -------------------о-----------
chromosomes IIa and IIb are homologs
IIA -----------------------о------------
IIB ------------------------о------------
Allele M is located on the long arm of chromosome Ia, and allele m is located at the same position on chromosome Ib
IA -------M----------о-----------
IB -------m----------о-----------
Allele P is located on the short arm of chromosome Ia, and allele p is located at the same position on chromosome Ib.
IA -------M----------о------P---
IB -------m----------о------p----
Allele R is located on chromosome IIa and allele r is located at the same position on chromosome IIb.
IIA ------------------------о------R----
IIB ------------------------о-------r----
Allele G is located on the long arm (q arm) of chromosome Ia, and allele g is located at the same position on chromosome Ib.
IA -------M---G-----о------P---
IB -------m----g-----о------p----
Allele N is located on the q arm of chromosome IIa and allele n is located at the same position of chromosome IIb.
IIA --------N--------------о------R----
IIB ---------n--------------о-------r----
A). Draw these chromosomes, identifying genes R, r, G, g, N, and n as they might appear in metaphase I of meiosis. Assume there is no crossing over.
IA ----------G-----о---------
IB -----------g-----о----------
IIA --------N--------------о------R----
IIB ---------n--------------о-------r----
During metaphase I, homologous pairs together migrate to the equatorial plane, where they randomly aline with their kinetochores facing opposite poles. The random arrangement of tetrads is different in every cell going through the meiosis process. There is no equal alinement between two cells. When tetrads aline in the equatorial plane, there is no predetermined order for each of the homologous chromosomes of each tetrad to face one of the poles and then migrate to it while separating. Any chromosome of the homologous pair might face any of the poles and then migrate to it. Each of the chromosomes has two possibilities for orientation at the plane. When the new haploid cells are formed, the number of variations in each cell is also different and depends on the chromosomes that form that cell. This random order in the equatorial plane is what introduces variation into the gametes. It is almost impossible that two gametes resulting from meiosis will get the same genetic charge.
B). Taking independent assortment and the subsequent random separation of chromosomes in anaphase I, draw the chromosomes, with genes identified, present in all possible gametes that could result once this cell completes meiosis. As above, assume there is no crossing over. Explain in your own words what is meant by independent assortment.
Independent assortment occurs when the alleles of two or more different genes distribute in the gametes independently from each other. In other words, a gamete receives an allele from a gene that does not depend on nor influence the allele of another gene in the same gamete. This can only be applied to independent genes. An organism gets only one of the members of the chromatids pair of each parent.
During gamete formation in meiosis, the pairs of homologous chromosomes separate after crossing over, and then chromatids sisters also separate, resulting in the formation of four gametes. Each gamete has different information from the combination of homologous chromosomes belonging to the father and to the mother.
There are four possible combinations, considering that there is no crossing over.
Gamete 1: GNRGamete 2: GnrGamete 3: gNRGamete 4: gnr
Inversion of DNA sequences within chromosomes is a common process in evolution. The following gene arrangements in a particular chromosome are found in four different species: First sequence: STUVWX Second sequence: UVXTSW Third sequence: UVWSTX Fourth sequence: SWVUTX Assuming that the arrangement in the first sequence is the ancestor/reference arrangement, in what evolutionary order did the four species arise, such that the fewest number of inversions occur between each species (place the first sequence as the earliest species in your ordering)2341
Answer:
The correct answer is - 1, 4, 3, 2.
Explanation:
It is given that the first sequence represents the earliest or ancestor species therefore, the first sequence would be - STUVWX
After the inversion, the highlighted sequence of the first sequence STUVWX gives rise to the second sequence as:
STUVWX
SWVUTX
Thus the second sequence after Ist inversion would be SWVUTX
2nd inversion, Third sequence:
SWVUTX
UVWSTX
Thus the third sequence after 2nd inversion is UVWSTX
3rd inversion, fourth sequence:
UVWSTX
UVXTSW
Thus, the fourth sequence after 3rd inversion is UVXTSW
why is vachellia nilotica classified as family level
Answer:
Vachellia nilotica is a flowering plant tree in the family Fabaceae.
Explanation:
A force of 5 N is required to increase the speed of a box from a rate of 1.0 m/s to 3.0 m/s within 5 s along a level surface. What change would most likely require additional force to produce the same results?
(SC.6.P.13.3)
reduce the mass of the box
increase the mass of the box
make the surfaces of the box smooth
make the surface of the floor smooth
HELPPP
Answer:increase the mass of the box
Explanation:
Big brain
The possibility of a baby having a certain genetic trait is in the ratio of 3.1. Give the probability of this occurring as a fraction and as a
percentage. Explain.
Tyn your answer below
brief explain the roles of the following in photosynthesis 1 NADP 2) Ribubose diphostate 3) photosytem 1 ad 2
Answer:
1) NADP is the reducing agent produced by the light reactions of photosynthesis and is consumed in the Calvin cycle of photosynthesis and used in many other anabolic reactions in both plants and animals.
3) Photosystems are the functional units for photosynthesis, defined by a particular pigment organization and association patterns, whose work is the absorption and transfer of light energy, which implies transfer of electrons. Physically, photosystems are found in the thylakoid membranes. There are two kinds of photosystems: photosystem I (PSI) and photosystem II
● PhotosystemSII acts first during the light transformation process in photosynthesis.
● Photosystem1 is an integral membrane protein complex that uses light energy to catalyze the transfer of electrons across the thylakoid membrane from
plastocyanin to ferredoxin. Ultimately, the electrons that are transferred by carrier NADPH.
What are CD4 cells?
a. T-cells that have a CD4 receptor
b. B-cells that have a glycoprotein receptor
c. HIV antigens
d. red blood cells
Answer:
I'm pretty sure it is b because CD4 cells are the cells that are a glycoprotein
Explanation:
prostate cells usually require testosterone and other androgens to survive. but some prostate cancer cells thrive despite treatments that eliminate androgens. one hypothesis is that estrogen, often considered a female, may be activating genes normally controlled by an androgen in these cancer cells. desribe one or more experiments to test this hypothesis
One can check for the translation and transcription of genes of interest in the absence of androgens, one can check whether the estrogen is involved in the expression of oncogenic proteins of interest by depleting the estrogen, and one can also examine the existence of estrogen receptor complex in the prostrate cancer cells nuclei.
• One can check for the translation and transcription of genes of interest in the non-existence of androgens and if these genes are expressed then this suggests that apart from androgens other factors also affect their expression.
• One can deplete the estrogen from cancer cells and if the involvement of estrogen is there in the expression of oncogenic proteins of interest then its reduction will result in diminished multiplication rates in cancer cells.
• One can also test the existence of estrogen-receptor complex in the prostate cancer cells nuclei to confirm that estrogen is taking part in the regulation of gene expression.
Thus, various experiments can be conducted to check that whether the expression of genes controlled by the androgens under normal conditions are affected by the presence of estrogens in prostate cancer cells.
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Antibiotics can be used to kill the specific pathogenic bacterium, Mycobacterium tuberculosis, that causes tuberculosis. The appearance of antibiotic-resistant strains has made it more difficult to cure M. tuberculosis infections. These antibiotic-resistant bacteria survive and pass on the genes to their offspring, making the resistant phenotype more common in the population. DNA analysis indicates that the genes for antibiotic resistance are not normally present in bacterial chromosomal DNA. Which of the following statements best explains how the genes for antibiotic resistance can be transmitted between bacteria without the exchange of bacterial chromosomal DNA?
a. The antibiotic-resistant bacteria release a hormone that signals neighboring bacteria to become resistant.
b. The genes for antibiotic resistance are located on a plasmid that can be passed to neighboring bacteria.
c. The antibiotic-resistant bacteria are the result of bacteria that specifically modify their own chromosomal DNA to neutralize the antibiotics
d. The antibiotic alters the bacterial genome of each bacterium, which results in an antibiotic-resistant population.
Answer:
b. The genes for antibiotic resistance are located on a plasmid that can be passed to neighboring bacteria.
Explanation:
Transformation is a genetic process by which bacteria take up foreign genetic material from the surrounding environment. In consequence, this process does not involve direct cell-to-cell interaction. Transformation allows the occurrence of horizontal gene transfer (HGT) events among different bacteria capable of exchanging extrachromosomal DNA plasmids, thus increasing genetic diversity in bacteria. Many different types of bacteria can acquire foreign genes, including antibiotic resistance genes, by HGT events involving plasmids, transposable elements, bacteriophages, etc.
what is peace and conflict??
What 3 types of science formed the geological time scale?
a) archaeology, paleontology, astrology
b) Scientology, astronomy, and geology
c) geology, archaeology, and paleontology
d) paleontology, Scientology, and biology
Answer: c) geology, archaeology, and paleontology
Explanation:
The geological time scale can be defined as a scale which is used to determine the chronological dating of the organisms in the geological strata. It helps in determining the occurrence and existence of particular kind of species on planet earth. It can also be used to trace the development and passage of a particular kind of trait from one generation to the another. It can also be used to trace back various geological events that occurred on planet earth like volcanic eruption, plate tectonics, and others. The geologists used it for tracing the geological activities that occurred in the history of earth. Archaeologist study about rocks and fossils to trace back the geological time scale. Paleontologist study the existence of a particular species via studying the fossil evidences and reconstructing the primitive conditions by developing a geological time scale. They trace the evolutionary history of organisms.
what is a reactant of photosynthesis
Answer:
water carbon dioxide and energy
the products are glucose and oxygen
Explanation:
What does it mean if a galaxy gives off light that has been shifted toward the red
end of the electromagnetic spectrum?
Answer: Redshift and blueshift describe how light shifts toward shorter or longer wavelengths as objects in space (such as stars or galaxies) move closer or farther away from us. ... When an object moves away from us, the light is shifted to the red end of the spectrum, as its wavelengths get longer.
Explanation:
What hypothesis explains why all birds share similar characteristics?
Answer:
this is a common ... saw incredible similarities between birds and the theropod dinosaurs (especially ... Like all other reptiles, birds have scales (feathers are produced by tissues similar to ... for theropods are often more serious for the "thecodont" pseudo-hypothesis.
Explanation:
Answer:
The modern version of the "from the ground up" hypothesis argues that birds' ancestors were small, feathered, ground-running predatory dinosaurs that used their forelimbs for balance while pursuing prey
Explanation:
help me woth these two ill give free BRAINLESS
Answer:
for 16 it is heart.
Explanation:
for 17 it is kidney to bladder
Answer:
16. skin & heart
17. kidney to the bladder
if 16 isn't multiple choice I'd say skin
tell me if it's right
