Describe the key features of the Watson-Crick model for DNA structure.

Answers

Answer 1

Answer:

Watson and Crick proposed the double helical model of DNA.

Explanation:

- This model says that DNA exist as double helix. It has two polynucelotide strands running in opposite direction i.e the strands are anti-parallel.

- Each polynucleotide strand is made up of several nucleotide liknked together by phophodiester bonds.

- The two strands are not coiled upon each other but the double strand is coiled upon itself around a common axis like the spiral stair case. Here base pairs forms the stairs and backbone of two strands form railing. Back bone contains sugar and phosphate.

- The base pairing is specific, adenine always pairs with thymine and guanine always pairs with cytosine. Thus if we see any base pair, it consists of one purine and one pyrimidine.

- The two strands of DNA thus show complementary base pairing.

- The strands are held together because of hydrogen bonding between the bases in opposite strand.

- One full helical turn involves ten base pairs and the base pairs are stacked  3.4 A apart.

- This form is called as B-form of DNA.


Related Questions

Differentiate between parental and recombinant gametes.

Answers

Answer: The two types of gametes are possible for when they are following genes that are on the same chromosomes. If they are crossing over, it does not occur, the products are known as Parental Gametes. If they are crossing over, the products are Recombinant Gametes. It is usually the simple matter that determine which of these gametes are recombinant gametes.

The difference between these two genes, is that are far apart and the frequency of recombination of genes is fifty percent. These genes that are closely located on the chromosome exhibit only have a few cross overs. The gametes that have recombined chromosomes, are known as Recombinant Gametes while the Parent Gametes are carrying on non-recombinant chromosomes.

I hope this helps you!

The surgical removal of male reproductive organs is known as _______________.

Answers

Answer: The surgical removal of male reproductive organs is known as Orchidectomy.

Explanation: By the process of Orchidectomy male reproductive organs ( one or both the testes ) removed surgically. Orchidectomy is also known as Castration.

Orchidectomy is very helpful in case of testicular cancer. Because in that case it serve as treatment of cancer.

Orchidectomy is of three types -:

1 : Simple -: In this type of orchidectomy male gonads and spermatic cord is removed by incision. For the treatment genetic infection.

2 : Subcapsular -: In this type of orchidectomy not the entire gland only glandular tissues are removed. It is a Prostrate cancer treatment.

3: Inguinal :- In this type one or both the testes or entire spermatic cord is removed in incision in lower abdomen.

Which of the following is a palindromic sequence?
a. AGGTCC
TCCAGG
b. CCTTCC
GCAAGG
c. GAATCC
CTTAGG
d. GGATCC
CCTAGG
e. GTATCC
CATAGG

Answers

Answer:

GGATCC

CCTAGG.

Explanation:

Pallindromic sequence may be defined as the sequence of the nucleotides that reads in the certain direction on which the strand reads and they are complementary to each other.

These sequences when read in 5' to 3' direction, the sequence is similar from 3' to 5' direction as well. The sequence  GGATCC when reads from the oppposite direction results in the same sequence CCTAGG. Hence, these are pallindromic sequences.

Thus, the correct answer is option (d).

The primary storage site for sperm is the seminal vesicles.
a. True
b. False

Answers

Answer:

The correct answer is option B. false.

Explanation:

The seminal vesicles are the site of production of the seminal fluid which makes 60 % of the total seminal vesicles. The seminal vesicles do not store the sperm.

The primary storage site of the sperm in seminiferous tubules and tubular storage sites for the sperm is  epididymis.

Thus, the correct answer is option B. false.

The molecular structure of water contains rwo atoms of hydrogen and one atom of oxygen when water reaches its boiling point and turns into water vapor what happens to its molecular structure
.

Answers

Answer:

Water molecules are isolated in its vapour form.

Explanation:

Water has polar molecules in all its form but when water becomes vapour its molecules became isolated. Their bond angles were bent at 105 degree. All the negative charges that is produced in water’s boiling point started concentrating the oxygen molecules and the positives were concentrating the hydrogen molecules.

However, the protons were partially positively charged. The electrons become 10 times greater near the oxygen than hydrogen.

Which of the following structures is NOT a part of the respiratory system?
a. external nares
b. uvula
c. epiglottis
d. choanae
e. mouth

Answers

Answer:

Uvula.

Explanation:

Respiration may be defined as the process of exchange of gases between the body tissue, lungs and the environment. Oxygen is inhaled and carbon dioxide is exhaled out during the process of respiration.

The choanae, external nares, epiglottis and mouth plays an important role in respiration. Uvula is mainly involved in the production of the salivary gland. The uvula moistens the area and also involved in the speech process. Hence, uvula do not play important role in respiration.

Thus, the correct answer is option (b).

Final answer:

Among the listed structures, the uvula is not a part of the respiratory system, it is a part of the digestive system and contributes in swallowing and speech.

Explanation:

The structure that is NOT a part of the respiratory system among the given options is (b) the uvula. The respiratory system includes structures through which air passes when we breathe, such as the external nares (nostrils), epiglottis (a flap that prevents food from entering the windpipe), choanae (rear openings of the nasal cavities), and the mouth. But the uvula, a dangling structure at the back of the throat, is a part of the digestive system, not the respiratory system. It plays a role in swallowing and speech.

Learn more about Respiratory System here:

https://brainly.com/question/4190530

#SPJ3

What are baroreceptors? Chemoreceptors?

Answers

Answer:

Baroreceptors:

Baroreceptors are the type of mechanical receptors. These receptors are located in the carotid sinus and become active in response to the change in the pressure in the heart. They have the ability to sense the information and relay it to the brain.

Chemoreceptors:

Chemoreceptors area also known as chemo sensors as they have the ability to detect the change in the chemical substance of the body. These receptors are present on the taste buds. They have the ability to generate the action potential and relay information.

Chlorophyll a is the primary plant pigment capturing light
forphotosynthesis and is a green color. How is this so when most
lightenergy for photosynthesis derives from red and
bluewavelengths?

Answers

Answer:

Chlorophyll a absorbs maximum light in blue and red regions of the spectrum while reflecting the green light.

Explanation:

The light reflected by any object reaches our eyes. “Chlorophyll-a” molecules are the pigments that do not absorb the green light and reflect it. The reflected green light imparts the chlorophyll-rich leaves a green color.

Since the absorption peak for Chlorophyll-a lies in red and blue regions of the spectrum, the maximum rate of photosynthesis is experienced in the presence of red and blue wavelengths.

The light absorbed by Chlorophyll-a drives light reactions to produce ATP and NADPH which in turn are consumed during the Calvin cycle to fix CO2 into glucose.

Which description accurately compares cellular respiration and photosynthesis?
A) Photosynthesis uses energy captured from sunlight to power the reduction of carbon dioxide to sugars; cellular respiration oxidizes sugars to yield energy for the cell.
B) The ATP produced via cellular respiration is needed to power the reactions of photosynthesis
C) The pathways of photosynthesis are those of cellular respiration run in reverse.
D) Photosynthesis captures energy from sunlight to oxidize carbon dioxide to sugars; cellular respiration reduces these sugars to yield energy for the cell.

Answers

Answer:

The correct answer will be option-A.

Explanation:

Photosynthesis is a process which uses sunlight energy to synthesize food in the form of glucose. The process takes place in the chloroplast in two stages: light-dependent reactions and light-independent reactions.

The light-independent reaction produces to convert the carbon dioxide from the atmosphere to glucose through the Calvin cycle. The carbon gets fixed and reduced form+4 state to +1 state.

Respiration is the process which oxidizes the glucose molecule to produce energy in the form of ATP molecules. This ATP is utilized by the cell to perform various functions.

Thus, option-A is the correct answer.

If 24% of an organism's DNA is thymine, what percent is cytosine?
a. 24%
b. 26%
c. 48%
d. 52%

Answers

Answer:

B. 26%

Explanation:

According to the Chargaff rule, we know that the quantity of thymine and adenine, and the quantity of cytosine and guanine are exactly the same in the DNA.

We can conclude that if there is 24% of thymine, there is also 24% of Adenine. Because those bases pair with each other and there is going to be the same percentage of them both in the DNA.

The sum of the 4 bases is going to be 100% in the DNA

[tex]A+T+C+G=100%[/tex]

Since 24% of the organism is thymine 24% is going to be adenine

[tex]24+24+C+G=100[/tex]

To know how much is missing from the equation we would have to subtract the total 48%  

[tex]C+G=100-48\\C+G=52\\[/tex]

This means that the remaining 52% is composed by the cytosine-guanine pairs. Since the pairs are equal in quantity in the DNA, we have to divide this number by 2 to have the amount of each one

[tex]C=\frac{52}{2} \\C=26[/tex]

The answer is: B.26% is going to be the percent of cytosine and also guanine in the DNA

The size of one copy of the human genome is approximately 3 billion base pairs, and it contains about 25,000 genes organized into 23 chromosomes. a. Human chromosomes vary in size. What would you predict is the size of the average chromosome? b. Assuming that genes are spread evenly among chromosomes, how many genes does an average human chromosome contain? c. About half of the DNA in chromosomes contains genes. How large (in base pairs) is an average human gene?

Answers

Answer:

a. Average size of chomosomes = [tex]130.435*10^6[/tex].

b. Average amount of genes per chromosome = 1086,95 genes per chromosome in average.

c. Average length of chromosomes = 1,5 billion base pairs.

Explanation:

a. Assuming the whole human genome is about 3 billion base pairs representing 23 chromosomes (one set), the size of an average chromosome can be estimated as [tex]3*10^9[/tex] base pairs /23, which equals to more  [tex]130,435*10^6[/tex] (more than 130 million base pairs).

This results due to the fact that 23 chromosomes contain [tex]3*10^9[/tex] base pairs (3 billion bp). Then 1 one them (in average) contains  [tex]3*10^9[/tex] base pairs/23. So,

Average size of chomosomes: [tex]3*10^9[/tex] /23=[tex]130.435*10^6[/tex]

b. If one assumes that genes are spread evenly among chromosomes, then the total amount of genes would be spread among the 23 chromosomes. Then, if one divides 25000 by 23, we are getting the amount of genes per chromosome.

Average amount of genes per chromosome: 25.000/23=1086,95 genes per chromosome in average.

c. If about half of the DNA in chromosomes contains genes, then half of 3 billion base pairs (representing 23 chromosomes) would be representing genes. Thus:

Average length of chromosomes: 3 billion base pairs / 2= 1,5 billion base pairs=  [tex]1,5*10^9[/tex] base pairs

Final answer:

The average human chromosome is approximately 130 million base pairs and contains about 1087 genes. The average gene size is roughly 238,000 base pairs.

Explanation:

a. The size of one copy of the human genome is about 3 billion base pairs. Given that human chromosomes number 23, the size of an average human chromosome would be roughly 130 million base pairs (approximately, 3 billion divided by 23).

b. If we take into account that the total number of genes is about 25,000, and they are spread evenly among the chromosomes, following the same logic, an average human chromosome would contain about 1,087 genes (approximately, 25,000 divided by 23).

c. Regarding the size of a gene in base pairs, it's worth noting that only half of the DNA in chromosomes contains genes, so each gene occupies a space of 2 times its actual size. If we take an average chromosome size of 130 million base pairs, each gene will comprise roughly 238,000 base pairs (130 million divided by 1087 times 2).

Learn more about Human Chromosome here:

https://brainly.com/question/38307495

#SPJ6

Which of these groups of animals currently has the greatest percentage of threatened species?
a. amphibians
b. birds
c. mammals
d. reptiles
e. fishes

Answers

Answer:

Amphibians, the total threated species is 31,8%

Explanation:

The IUCN ( International Union for Conservation of Nature) is an environmental organization that helps and influences societies around the world to preserve biodiversity so that human progress, economic diversity and the conservation of nature can work together, to ensure that any natural resource usage is ecologically sustainable.

The IUCN created a list of threatened species. A threatened species is an organism that is vulnerable to lose all of its population shortly.  The list was created to state and report the status of conservation of animals and plants. The IUCN studies species under several conditions and criteria to create a list of categories directed toward classifying animals and taking action when needed:  

Extinct (EX): the last individual of the species has died. Extinct in the wild (EW): the last individuals is known only to survive in captivity Critically endangered (CR): the species is in extremely high risk of extinction in the wild in the immediate futureEndangered (EN): the species is in very high risk of extinction in the wild shortly.Vulnerable (VU): the species is a high risk of extinction in the wild in medium-term futureNearly Threatened (NT): the species is close to being at high risk of extinction soon Low Concern (LC): the species is unlikely to become extinct soon.Deficient Data (DD): Not enough information about the species to classify it. Not Evaluated (NE) : the species have not been evaluated yet

The definition of threatened according to the IUCN is a species that is classified in CR (Critically endangered) , EN (Endangered) , and VU (Vulnerable)

So according to this definition in the IUCN red list finder, you would have the following numbers:

a. Amphibians  

Total: 6771Threatened: CR: 575, EN:944; VU: 638 Total threatened: 2157Percentage: 31,8%

b. Birds

Total: 11133Threatened by category: CR: 225, EN: 469, VU: 799Total threatened: 1493Percentage: 13,4%

c. mammals

Total: 5801Threatened by category: CR: 203, EN: 489, VU:528 Total threatened: 1220Percentage: 21%

d. reptiles

Total: 7541Threatened by category: CR: 303, EN: 547, VU: 517Total threatened: 1367Percentage: 18,1%

e. fishes

Total: 18449Threatened by category: CR: 549, EN: 771, VU: 1174Total threatened: 2494Percentage: 13,5%

Answer: Amphibians, the total threated species is 31,8%

Final answer:

Amphibians have the greatest percentage of threatened species among the groups listed, with 29% of all amphibians classified as threatened. This calls for urgent conservation efforts to mitigate further losses.

Explanation:

Among the options provided, the group of animals currently with the greatest percentage of threatened species is amphibians. According to the International Union for the Conservation of Nature, up to 29 percent of all amphibians are classified as threatened, a rate higher than that for other groups mentioned, such as mammals, birds, reptiles, and fishes. This alarming percentage highlights the urgent need for conservation efforts to prevent further losses within this class.

Amphibians are facing numerous threats, including habitat loss, pollution, climate change, and infectious diseases, which collectively contribute to their high rate of endangerment. Efforts like the Biodiversity Action Plan, ratified by 188 countries, aim to protect these vital species and their habitats. Understanding and supporting such conservation initiatives is crucial for preserving the biodiversity of our planet.

Vitamins are inorganic compounds used by the body for metabolism.
a. True
b. False

Answers

The correct answer is A. False

Explanation:

Vitamins are organic compounds or molecules rather than inorganic ones which means they are mainly composed of carbon and they are related to living organism different from minerals that come from non-living elements such as water or earth. Vitamins are essential for the metabolism in an organism including functions such as growth due to this, they are necessary but in most cases only in small quantities. Additionally, vitamins are obtained through diet or similar rather than synthesize by the organism. According to this, it is false "Vitamins are inorganic compounds used by the body for metabolism" because even though they are necessary for the metabolism, vitamins are organic and not inorganic compounds.

Which method allows the rapid and simultaneous screening of the expression of thousands of genes?
a. RT-PCR
b. Northern blot analysis
c. immunoprecipitation
d. microarray
e. haplotype identification

Answers

Answer:

d. microarray

Explanation:

Microarray is a type of chip that is allows high-throughput screening of multiple genes. They are quicker and produce large data that is usually analyzed using bioinformatic tools.

The atomic number of sulfur is 16. Sulfur combines with hydrogen by covalent bonding to form a compound, hydrogen sulfide. Based on the number of valance electrons in a sulfur atom, predict the molecular formula of the compound.
a. HS c.H2S
b. HS2 d. H4S

Answers

Answer:

H2S.

Explanation:

Ions may be defined as the element that contains either positive or negative charge over them. Two types of ions are cations and anions. The outermost electrons are involved in the formation of ions.

The atomic number of sulfur is 16. Its outermost electronic configuration is K=2, L= 8, M= 6. The sulfur requres two more electrons to complete its orbit and accquire -2 charge.

H        S

+1        -2

Then, the formula will be H2S.

Thus, the correct answer is option (c).

Lipid-soluble signaling molecules, such as aldosterone, cross the membranes of all cells but affect only target cells because
a. only target cells retain the appropriate DNA segments.
b. intracellular receptors are present only in target cells.
c. only target cells have enzymes that break down aldosterone.
d. only in target cells is aldosterone able to initiate the phosphorylation cascade that turns genes on.

Answers

Answer: The correct answer is option b.

Explanation:

Aldosterone is a mineralocorticoid, that is, a steroidal hormone that plays important role in regulating blood pressure as well as the levels of sodium and potassium in the plasma.

It is released from adrenal gland. Being steroidal in nature, it is capable of bypassing plasma membrane easily.

However, its receptors are present inside the cell, that is, in cytoplasm.

These receptors are expressed or present only in the target cells due to which this hormone produces its effects only in the target cells.

Once bound to intracellular receptor, the cell signalling results in alterations in gene expression which produces the desired effects.

Final answer:

Lipid-soluble signaling molecules, like aldosterone, affect only target cells because intracellular receptors are present only in target cells.

Explanation:

Lipid-soluble signaling molecules, such as aldosterone, affect only target cells because intracellular receptors are present only in target cells. These receptors are specific to the signaling molecule and are located inside the cell. When aldosterone enters a target cell, it binds to its corresponding intracellular receptor, leading to a series of events that ultimately activate or inhibit specific genes responsible for cellular responses. This selectivity ensures that only certain cells respond to aldosterone.

Learn more about Lipid-soluble signaling molecules here:

https://brainly.com/question/39287010

#SPJ3

All embryos appear female during early development.
a. True
b. False

Answers

Answer:

True

Explanation:

Geneticists have discovered that all human embryos start life as females. In the early development in the embryonic stage, this is true both for humans and mammals. This changes only at the 2nd month (in the case of humans, since different mammals have different gestating periods) if the embryo can elaborate enough androgens (dominant male hormone) to offset the maternal estrogens (dominant female hormone) then, maleness develops.

Distinguish between a monohybrid cross and a testcross.

Answers

Answer:

Monohybrid cross:

Monohybrid cross may be defined as the cross done by taking single trait at a time. The ratio of the monohybrid cross by the pure parent breed result in the formation of 3:1 phenotype in the second generation.The genotype ratio is 1:2:1.

Test cross:

Test cross may be defined as the cross between the unknown genotype and the recessive parents. This cross is done to determine whether the genotype is heterozygous or the homozygous dominant trait. The ration of the cross may vary depending on the genotype of the organism.

Which of the following involves metabolic cooperation among prokaryotic cells?
a.binary fission c.biofilms
b.endospore formation d.photoautotrophy

Answers

Answer: c. Biofilm

Explanation:

Metabolic cooperation between prokaryotes

allows them to use the resources that they could not use when they are living as single cell. Bio film is the example of the metabolic cooperation.

Bio films are formed by the colonizing of single type of prokaryote such as bacteria and they facilitate the growth of other bacteria on the surface by secreting the substances essential for their growth.

Hence, the correct option is (c) biofilms.

Final answer:

The process that involves metabolic cooperation among prokaryotic cells is biofilms. These are communities of microorganisms that cooperate metabolically to carry out functions

Explanation:

The process that involves metabolic cooperation among prokaryotic cells is c. biofilms. Biofilms are communities of microorganisms that stick to each other and often to a surface. These adherent cells are frequently embedded within a self-produced matrix of extracellular polymeric substances (EPS). Biofilms may form on living or non-living surfaces and can be prevalent in natural, industrial, and hospital settings. They certainly demonstrate the metabolically cooperative characteristics of prokaryotic cells, where the cells work together to carry out functions that they couldn't perform individually.

Learn more about Biofilms here:

https://brainly.com/question/33436158

#SPJ6

Distinguish between the effects of mutation in somatic and germ-line cells.

Answers

Answer:

Somatic cells:

When normal body cells mutate usually the effects are harmful in different ways which end up killing the cell.

Another type of scenario is where the cells survives but cells from the immune system recognized it and end up killing it.

sometimes somatics cells can accumulate mutations and survive which leads to a tumor or cancer.

Germ-line:

When germ-line cells produce gametes with mutations this mutations can end up killing the embryo. If the embryo survives the mutation can generate all sorts of genetic disorders, the spectrum here is massive and depends on the site of the DNA mutation.

Is the Gram stain a useful tool for understanding the phylogeny of eubacteria? Explain why or why not.

Answers

Answer

Yes, Gran stain is a useful tool for unterstanding the phylogeny of eurobacteria.

Explanation

The Gram staining method is used to classify two broad groups: gram-positive and gram-negative bacteria. This technique is widely used in clinical analysis and microbiology laboratories to monitor infections in pus smears or organic fluids.

In the Gran staining method, we subject the bacteria to dye treatments and, depending on the chemical composition of the cell wall of these bacteria, each one will react differently with the dyes and thus identify them by their biochemical characteristics.

Final answer:

The Gram stain is pivotal for classifying bacteria into gram-positive and gram-negative groups but is not a dependable method for elucidating the phylogeny of eubacteria, as it focuses on cell wall characteristics rather than genetic relationships.

Explanation:

The Gram stain is a differential staining technique that was developed as an efficient method to differentiate bacteria based on the structural differences in their cell walls. Although invaluable for identifying and classifying bacteria into gram-positive and gram-negative groups based on their reaction to the stain, the Gram stain itself is not a reliable tool for understanding the phylogeny of eubacteria.

Phylogeny involves the evolutionary relationships among organisms, which require more comprehensive genetic analysis rather than just cellular characteristics discerned from staining techniques. Nevertheless, the Gram staining method is a foundational first step in identifying bacterial species and understanding aspects of their cell wall structure that can hint at broader taxonomic relationships.

compare the relative energy storage of carbohydrates, lipids, and proteins. (NEED ANSWER QUICKLY NEED TO TURN THIS IN TONIGHT OR IM GONNA FAIL PLS HELP)

Answers

Proteins

Protein is used for the growth and repair of cells and can be used as a source of energy if carbohydrate and fat reserves are low.

Proteins are made up of long chains of amino acids.

After digestion amino acids are absorbed into the bloodstream and brought to cells that reassemble them into proteins needed by the body (e.g. enzymes).

Foods high in protein include fish and eggs.

Cellulose, starch and glycogen are complex carbohydrates. They are long chain of sugars joined together.

Carbohydrates

Carbohydrates provide energy. There are two types - simple and complex.

Simple carbohydrates are sugars, like glucose and lactose. They are a fast acting source of energy, like biscuits or energy bars.

Complex carbohydrates are a source of slow release energy, like rice and pasta.

Cellulose – is found in plant cell walls and cannot be digested by humans. However, as fibre, it helps the muscles of the intestinal wall push food through the digestive system

Starch – is broken down by digestive enzymes into glucose, which can be used by cells to make energy

Glycogen – is a carbohydrate store within the human body and can be converted into glucose when levels are low

Fats/lipids

Fats are a store of energy, providing double the energy that carbohydrates and proteins do.

They are made up of fatty acids and glycerol.

Foods high in fat include cheese, butter and oils.

Lipids (fats) provide the most efficient and dense energy storage, making them suitable for long-term energy reserves, while carbohydrates serve as a readily available energy source for quick bursts of activity. Proteins are not primarily used for energy storage due to their critical roles in various cellular functions.

The comparison of the relative energy storage of carbohydrates, lipids, and proteins:

Carbohydrates are a quick and easily accessible source of energy for the body. They are stored in the form of glycogen in the liver and muscles. Glycogen can be rapidly broken down into glucose to provide energy during times of high demand, such as exercise. However, the storage capacity for glycogen is relatively limited compared to other energy storage molecules.

Lipids, specifically triglycerides, are highly efficient energy storage molecules. They provide the most energy per unit mass compared to carbohydrates and proteins. Lipids are stored in adipose tissue throughout the body. They have a lower water content compared to carbohydrates, making them more compact and providing a dense energy source. This energy reserve is important for long-term energy needs and insulation.

Proteins are not typically a primary energy storage molecule. Their main functions include structural support, enzymatic activity, and cell signaling. While proteins can be broken down into amino acids that can be used for energy in times of extreme need, the body prefers to preserve proteins for their essential functions rather than utilizing them as a primary energy source.

To know more about carbohydrates here

https://brainly.com/question/33874241

#SPJ3

The concentration of CO2 in the atmosphere globally (choose any/all that apply, points deducted for incorrect answers):
a. has a greater annual variation in the northern hemisphere than in the southern hemisphere
b. has a greater annual variation in the southern hemisphere than in the northern hemisphere
c. has an annual variation globally that is constant regardless of location
d. varies annually depending on rates of marine NEP
e. varies annually depending on rates of terrestrial NEP

Answers

Answer:

a. has a greater annual variation in the northern hemisphere than in the southern hemisphere

Explanation:

These latitudinal fluctuation variations are the consequence of plant photosynthetic activity. As plants begin to photosynthesize in the spring and summer, they consume CO2 from the atmosphere and eventually use it as a carbon source for growth and reproduction. This leads to the decline in CO2 concentrations beginning in May each year. By reducing photosynthesis, crops save energy once winter comes. The dominant method, without photosynthesis, is ecosystem CO2 exhalation (cellular respiration and decomposition), including bacteria, crops, and livestock.

Two latitudes of Earth contain most of land plants: Northern Hemisphere mainlands and the tropics that envelop, among different territories, the immense downpour woods of the Amazon basin. Close to the equator temperature are constant all year long. Shifts in CO2 are hence most articulated in the Northern Hemisphere, where the regular changes in temperature bring about enormous contrasts in plant photosynthesis from summer to winter.

Describe the helical and coiled-coil structures of either collagen or α-keratin. What type of covalent bond holds the coiled-coils in staggered arrangements to form larger fibrous structures of this protein?

Answers

Answer:

Collagen is an extracellular matrix protein and one of the most abundant protein in the body. Its triple-helical structure is a result of the 3 coiled chains. Each chain mainly comprises of Glycine, Proline and Hydroxyproline. The Glycine hydrogen bonds with residues of the adjacent chain while the proline and hydroxyproline C-N bonds provide stability in the structure.

Explanation:

The ATP and NADPH produces in the light reaction are used to drive the synthesis of sugars from CO2.
a. True
b. False

Answers

Answer:

The correct answer will be option-true.

Explanation:

Photosynthesis reaction proceeds in two phases: light-dependent and light-independent reaction.

During light-dependent reaction which takes place in thylakoid membrane intermediates like ATP and NADPH are produced through electron transport chain.  

These intermediates are directly utilized in the light-independent reaction which performs cyclic reactions known as the Calvin cycle. Calvin cycle produces glucose molecules using ATP and NADPH in the reactions.

Thus, option-true is the correct answer.

What information about the structure of DNA was obtained from X-ray crystallographic data?

Answers

Answer:

With the crystallographic data you can obtain the space between the base paris on the DNA, yo can also predict that the DNA have a double helix structure, and with this information and some chemical simulations you can obtain the exact amount of nucleotides in each turn.

what is a substance that cannot be broken down to other substances by ordinary chemical means?

Answers

Answer:

The correct answer is an element.

Explanation:

An element refers to a component whose atoms comprises a similar number of protons, or it can be said that the atoms of a specific element exhibit the same atomic number. Chemically, they are the simplest components, which cannot be further differentiated by any chemical means. The elements can get converted into other elements with the help of nuclear methods.

If a female who is a carrier for a sex-linked trait mateswith
a male who expresses the trait, what is the chace that her sonwill
express the trait?
A) 1/4
B) 1/2
C) all of her sons will express the trait
D) none of her sons will express the trait
for lifesaver, explain the reasoning for
youranswer.......

Answers

Answer:

B) 1/2

Explanation:

A sex linked trait is passed via sex chromosomes. Here the given trait is X linked recessive because female carrier is not possible for X linked dominant trait.  

For X linked recessive trait:

Carrier female = XCXc

Affected male = XcY

Their progeny:

        XC    Xc  

Xc   XCXc  XcXc

Y    XCY     XcY

Out of the sons, half will be not affected ( XCY ) and half will be affected  ( XcY )

Hence, half of the sons will express the trait.

Which of the following statements is a correct distinction between autotrophs and heterotrophs?
a. Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic.
b. Only heterotrophs require chemical compounds from the environment.
c. Cellular respiration is unique to heterotrophs.
d. Only heterotrophs have mitochondria.

Answers

Answer:

a. Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic.

or

b. Only heterotrophs require chemical compounds from the environment.

Correct option is A. Autotrophs can create organic molecules from inorganic nutrients like CO², whereas heterotrophs need organic compounds to survive.

The correct distinction between autotrophs and heterotrophs is that autotrophs, but not heterotrophs, can nourish themselves beginning with CO² and other nutrients that are inorganic. This means that autotrophs are capable of synthesizing organic molecules from inorganic nutrients, such as carbon dioxide and water through the process of photosynthesis. They do not need pre-packaged organic compounds to survive, unlike heterotrophs, which require organic forms of carbon and depend on the complex organic compounds produced by autotrophs for nutrition.

Type of nitrogenous base with a double ring found in DNA and RNA:
a. Ribose
b. purine
c. pyrimidine
d. cytosine

Answers

Answer:

The correct answer will be option-B (purine).

Explanation:

Nucleic acid structure is made up of monomer unit called nucleotide. Each nucleotide is composed of a five-carbon sugar, a phosphate group and five types of nitrogenous bases.

The nitrogenous bases are categorized in two forms the purines (adenine and guanine ) and the pyrimidines (cytosine, thymine and uracil). The "purines" contain double rings in their structure due to which they appear larger in size than pyrimidines which are made up of single rings.

Thus, Option-B is the correct answer.

Other Questions
Water enters a 4.00-m3 tank at a rate of 6.33 kg/s and is withdrawn at a rate of 3.25 kg/s. The tank is initially half full. Repeat the calculation for the time until overflow for the case of water entering a 4.00-m3 tank at a rate of 6.83 kg/s and withdrawn at a rate of 3.50 kg/s. The tank is initially two thirds full. You throw a ball upward with a speed of 14 m/s. What is the acceleration of the ball after it leaves your hand? Calculate the percent errorin a length measurementof 4.45cm if the correct value is 4.06 Find two consecutive odd integers such that 77 more than the lesser is six times the greater.The lesser consecutive odd integer is _ and the greater consecutive odd integer is _ A MEAL paragraph can be the introduction or the conclusion of a paper. TrueorFalse ?? A lithium atom has positively charged protons and negatively charged electrons. The sum of the charges represents the charge of the lithium atom. Find the charge of the atom. Gertrude is very environmentally-conscious, so she only uses paper bags at the grocery store and tries to purchase items in packages that are recyclable. Her behavior concerns which type of situation? Will day lenght change faster near the equinox or near thesolstices? (35 pts)Evaluate the reasoning provided by both students A and B and correct the errors Make sure to provide proper reasoning. Only answer if you know your answer is correct please. Write the equation of the line. Give your answer in Standard Form Melanie has just received an exam grade in her psychology class. She earned a grade of 89 percent, which is a B. All of her work during the semester thus far has earned A grades, and she is very upset about the exam score. "This is the worst thing that could possibly have happened," she laments to her best friend, Keesha, who just rolls her eyes. A cognitive psychologist would suggest that Melanie is employing the cognitive distortion called _________. how can you use a formula for one measurement to write a formula for a different measurement? Comparing Order of Magnitude A biologist estimated the number of cells in a culture sample as 1.3 102. One week later, he looked at the same culture sample and estimated that the number of cells had grown to 3.9 105. Determine how many times larger the culture sample was compared to a week earlier. (3.9 105) (1.3 102) Complete the quotient in scientific notation and find the solution in standard notation. = where does cell produce atp True or False: When using the endpoint mover, you will receive credit for each endpoint that is positioned correctly. What is the measure of ACD?A.30B.63C.147D.150Please help :) 8. A cookie recipe calls for of a cup of flour and makes 2 dozen cookies.a. If you plan to make 8 dozen cookies, how many cups of flour do you need?- b. How many cookies can you make if you have 10 cups of flour and want to use it all? Consider the reaction: 2A(g)+B(g)3C(g).Part ADetermine the expression for the rate of the reaction with respect to each of the reactants and products.a) Rate=13[A]t=[B]t=12[C]tb) Rate=12[A]t=[B]t=13[C]tc) Rate=[A]t=12[B]t=13[C]td) Rate=12[A]t=12[B]t=13[C]tPart BWhen A is decreasing at a rate of 0.100 Ms1 , how fast is B decreasing?Part CHow fast is C increasing? How do his words reflect politics in shakesperes day? For two 0.2 m long rotating concentric cylinders, the velocity distribution is given by u(r) = 0.4/r - 1000r m/s. If the diameters are 2 cm and 4 cm, respectively, calculate the fluid viscosity if the torque on the inner cylinder is measured to be 0.0026 N*m.