Answer: True
Explanation:
The DNA cloning techniques have made the manipulation of genes possible. The cloning of DNA have made it possible that new organism can be made which is genetically identical to the organism from which it is being cloned.
The manipulation of the gene for the mixing and matching of genes is also possible with the help of the cloning.
It is one of the application of genetic engineering which allows to map, manipulate and transfer genes among organism.
The formation of ATP in a muscle cell is an _______________ reaction, whereas using ATP for contraction is an _____________ reaction
Answer:
1. endergonic
2. exergonic
Explanation:
The formation of ATP is an endergonic reaction. It means that the reaction requires the input of energy to be performed. Muscle cells form ATP mainly during the oxidative phosphorylation of cellular respiration. The proton concentration gradient across the inner mitochondrial membrane drives the endergonic phosphorylation of ADP into ATP. ATP hydrolysis releases energy and is an exergonic reaction. Removal of the phosphate group reduces the electrostatic repulsion between the negative charges present on the three phosphate groups of ATP.
The formation of ATP in a muscle cell is an endothermic reaction and using it for muscle contraction is exothermic. Creatine phosphate helps replenish ATP during muscle contractions, and different pathways are used depending on the presence of oxygen.
The formation of ATP in a muscle cell is an endothermic reaction, whereas using ATP for contraction is an exothermic reaction. The creatine phosphate system operates to regenerate ATP. When oxygen levels are high, ATP combines with creatine to form ADP and creatine phosphate, storing energy. As ATP levels fall during muscle contractions, this reaction reverses to quickly resupply ATP. In the presence of oxygen, cells also produce ATP through aerobic respiration, whereas in its absence, ATP is derived from anaerobic respiration. Moreover, different muscle fibers like slow oxidative (SO), fast oxidative (FO), and fast glycolytic (FG) have varying abilities to regenerate ATP, which consequently affects their contraction dynamics and fatigue rates. Aerobic metabolism is the primary method for sustained muscle contraction, as it can produce more ATP than the other two mechanisms.
Sexual selection favors individuals with traits that increase their ability to obtain mates, such as mating calls in crickets. Using this example, propose a scenario where sexual selection could contribute to divergence in sympatric speciation.Drag the terms on the left to the appropriate blanks on the right to complete the sentences.male(s)female(s)cool forest floorwarm forest canopyVariation in ________ calls could occur, such as a lower-pitched call at the _______ and a higher-pitched call in the _______. _______ in the _______ could start to prefer _______ with lower-pitched calls, and ________ in the _________ could start to prefer _________ with higher-pitched calls, creating genetic isolation. Over time, genetic divergence could occur between the two populations.
Answer:
variation in male calls could occur, such as a lower-pitched call at the cool forest floor and a higher-pitched call in the warm forest canopy. Females in the forest floor could start to prefer males with lower-pitched calls, and females in the canopy could start to prefer males with higher-pitched calls, creating genetic isolation. Over time, genetic divergence could occur between the two populations.
Select the reasons why viruses, prions, and viroids are not classified as living organisms. a. They are not able to reproduce independently. b. They are only motile in the early stages of growth. c. They do not use energy for metabolism of any kind. d. Their virulence is maintained by non-living cultures.
Answer: Viruses, prions, and viroids are not classified as living organisms because they are not able to reproduce independently, and they do not use energy for metabolism of any kind. Option A and C
Explanation:
Viruses, prions and viroids are not classified as living organisms because they are not made out of cells, they are not able to reproduce independently, and they do not use energy for metabolism of any kind.
What is the nutritive fluid flowing through the circulatory system? A. Lymph B. Blood C. Pus D. Water
Answer: The answer is blood
Explanation:
The blood is the 'fuel' of the circulatory system in that it carries nutrients ranging from
- gases like oxygen by the help of its respiratory pigment, hemoglobin
- rich food substances like glucose, amino acids to various cells of the body
- antibodies and hormones that provide defence against invaders
Thus, the blood is the nutritive fluid of the circulatory system
The nutritive fluid flowing through the circulatory system is Blood, transporting nutrients and waste materials. Lymph, another body fluid, functions primarily in the lymphatic system.
The nutritive fluid that flows through the circulatory system is B. Blood. Blood, a type of fluid connective tissue, circulates within the body, transporting nutrients, salts, and waste materials. It consists of cells, like red and white blood cells, suspended in a liquid matrix called plasma.
Lymph is another important fluid in the body that functions mainly in the lymphatic system. It is a watery fluid that bathes tissues and organs and contains protective white blood cells. It does not circulate throughout the body in the same way as blood and is not pressurized by the heart. Lymph moves in one direction from extremities towards two drainage points into veins just above the heart.
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What are the roles of the parasympathetic nervous system and sympathetic nervous system in maintaining everyday homeostasis?
Answer: The parasympathetic nervous system and sympathetic nervous system play opposite roles
Explanation:
To ensure a stable internal environment (homeostasis) is achieved, the parasympathetic nervous system (PNS) and sympathetic nervous system (SNS) play OPPOSITE roles.
The PNS dominate during relaxed periods and stimulates the
- liver to break down glycogen
- constriction of bladder to pass out urine
- increases heartbeat
- dilate pupils etc
The SNS, in contrast dominate in times of emergency or stressful periods and do the EXACT opposite of the processes mentioned above.
Thus homeostasis is maintained
The mathematical symbol for period is
ОА. Т
ОВ. А
O co v
OD. f
Answer: The mathematical symbol for period is T
Explanation:
Period is the time taken for an object to complete a full cycle or revolution. Period is mathematically represented by the letter T, and is measured in seconds.
Afterbirth includes all of the following EXCEPT: Question 3 choices Choice A.,fluid from the amniotic sac. Choice B.,the placenta. Choice C.,the umbilical cord. Choice D.,other membranes.
Answer:
A) fluid from the amniotic sac
Explanation:
Afterbirth involves the expulsion of placenta, umbilical cord and fetal membranes from the uterus followed by the birth of child. While the fluid from the amniotic sac is released before or during the labor which is also called water breaking.
The term afterbirth refers to the placenta, umbilical cord, and other membranes that are expelled from the mother's body after the birth of a child. Option A is likely the correct answer
Explanation:The term afterbirth refers to what is expelled from the mother's body after the birth of a child, which is the third stage of childbirth. It typically includes the placenta, the umbilical cord, and other membranes that surrounded the baby in the womb, such as the amnion and chorion.
Regarding the options given in your question, all of them are generally included in the afterbirth EXCEPT for Choice A: Fluid from the amniotic sac. The amniotic fluid, which surrounds and cushions the baby during gestation, is generally expelled during the process of labor and delivery (often referred to as when a mother's 'water breaks') rather than after the birth itself. Hence, option A is likely the correct answer to your question.
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This popular drug alters consciousness by blocking the reuptake of dopamine and increases its release, and in the long term, it can cause considerable damage throughout the brain and body.
A. marijuana
B. MDMA
C. meth
D. heroin
Answer: Meth
Explanation:
Meth is a stimulant that affects the "Pleasure Reward Pathway" by altering the reuptake of the neurotransmitter dopamine, consequently leaving an excess dopamine in the synapse. It also increases the activity of the dopamine synthesizing enzyme Tyrosine Hydrolase, thus ensuring continuous release.
Yaws is a serious skin disease of children in tropical countries, caused by Treponema pertenue, a species closely related to the bacteria that cause syphilis. Individual cells of T. pertenue are helical, relatively long, and flexible like the one pictured below. These cells are known as _____.
Answer:
The correct answer is- spirochetes
Explanation:
Spirochetes are a group of bacteria which are long, flexible and helical shaped. Some of them are associated with some disease in humans like yawns, lime disease, syphilis, etc.
Yawn is childhood infectious disease caused by a spirochete bacteria called Treponema pallidum pertenue. These bacterial usually affect the children who live in tropical regions like Africa, Southeast Asia. They can affect skin, bones, and joints. They can spread through direct contact with skin sores.
So the cells of T. pertenue which are helical, relatively long, and flexible known as spirochetes.
Three populations of crickets look very similar, but the males have courtship songs that sound different. What function would this difference in song likely serve if the populations came in contact?
A) a behavioral reproductive isolating mechanism
B) a temporal reproductive isolating mechanism
C) a gametic reproductive isolating mechanism
D) a postzygotic isolating mechanism
Answer:
Answer is A. a behavioral reproductive isolating mechanism.
Explanation:
A behavioral isolation mechanism can be described or explained as a mechanism whereby , mating rituals or signals of species of an organism are different from one another , in order to prevent interbreeding or interest in courtship among them.
In this case , the organisms in the population may be similar, and have the tendency of interbreeding, but , because of their different mating or courtship signals, the interbreeding won't be possible.
This difference in song likely serve if the populations came in contact due to function - A) a behavioral reproductive isolating mechanism
Behavioral reproductive isolating mechanism
Species are reproductively isolated by various mechanisms, one of which is due to the behavior. Singing is a mating call if the song is different mating will not happen and it is termed as a behavioral isolating mechanism for reproduction.
Temporal isolation is with respect to the time when different species mate during a different time. Postzygotic, zygotes become infertile after fusion. Gamete isolation two different gametes don't fuse and hence no formation of zygote.
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The correct functions of your lungs contribute to the normal pH level of between 7.35 and 7.45 in your blood. If your lungs do not exchange and remove carbon dioxide from your blood, the blood pH will change. A reading of pH 6.4 of your blood indicates:A. no health risk, as part of normal pH changes in your body that in this case bring it closer to neutral pH.B. a health problem due to the concentration of hydrogen ions (H+) being 10X higher than normal in your body.C. a health problem due to the concentration of hydroxide ions (OH-) being 2X higher than normal.D. a health problem due to the concentration of hydrogen ions (H+) being 2X higher than normal in your body.E. a health problem due to the concentration of hydroxide ions (OH-) being 10X higher than normal in your body.
Answer:
B
Explanation:
The lung not being not been able to exchange and remove the carbon dioxide created a health problem due to the concentration of hydrogen ions (H+) being 10X being higher than in normal body. Although the difference is just about 1, it will result increase hydrogen ion concentration 10 times, similarly an increase or decrease in pH from 4 to 2 will give rise to 100 times increase in hydrogen ion concentration. It can equally be applied to hydroxyl in concentration.
Contrast the genetic content and the origin of sister versus nonsister chromatids during their earliest appearance in prophase I of meiosis.
Complete question:
Question: Contrast the genetic content and the origin of sister versus nonsister chromatids during their earliest appearance in prophase I of meiosis.
a) Sister chromatids are genetically similar, except where mutations may have occurred during DNA replication. Nonsister chromatids are genetically dissimilar.
b. Sister chromatids are genetically identical, except where mutations may have occurred during DNA replication. Nonsister chromatids are genetically similar if on homologous chromosomes and genetically dissimilar if on nonhomologous chromosomes.
c. Sister chromatids are genetically identical, except where mutations may have occurred during DNA replication. Nonsister chromatids are genetically similar.
d. Sister chromatids are not genetically similar, except where mutations may have occured during DNA replication. Nonsister chromatids are genetically similar if on homologous chromosomes and genetically dissimilar if on nonhomologous chromosomes.
Answer:
b. Sister chromatids are genetically identical, except where mutations may have occurred during DNA replication. Nonsister chromatids are genetically similar if on homologous chromosomes and genetically dissimilar if on nonhomologous chromosomes.
Explanation:
A chromosome has two chromatids after the S phase of the cell cycle. The replicated DNA molecules are accommodated in the sister chromatids. Therefore, two chromatids of a chromosome carry the identical DNA molecule and are genetically identical to each other. The sister chromatids may carry different genes if one or more mutation occurs in their DNA.
Two chromatids of two different chromosomes are called non-sister chromatids. Homologous chromosomes are the chromosomes that are similar in morphology and genetic constitution. Therefore, two chromatids of a homologous pair are also non-sister chromatids but have genetically identical sequences. For example, the two non-sister chromatids of the pair of chromosome 21 in humans carry the alleles for the same genes.
However, the non-sister chromatids that belong to nonhomologous chromosomes carry different genes and are not genetically identical.
A global alignment algorithm (such as the Needleman-Wunsch algorithm) is guaranteed to find an optimal alignment. Such an algorithm:________.
A) Puts the two proteins being compared into a matrix and finds the optimal score by exhaustively searching every possible combination of alignments.
B) Puts the two proteins being compared into a matrix and finds the optimal score by iterative recursions.
C) Puts the two proteins being compared into a matrix and finds the optimal alignment by finding optimal sub-paths that define the best alignment(s).
D) Can be used for proteins but not for DNA sequences %.
Answer:
Option (C).
Explanation:
The alignment of the particular sequence can be used to determine the property, structure or the evolutionary relationship of the particular gene. The BLAST ca be used for the alignment.
Needleman-Wunsch algorithm is used to understand the alignment of the molecules especially protein and nucleotides. In this case, the two different proteins or molecules are compared by using the optimal alignment and the sequence is then determined.
Thus, the correct answer is option (C).
The Needleman–Wunsch algorithm is an algorithm used in bioinformatics to align protein or nucleotide sequences. It was one of the first applications of dynamic programming to compare biological sequences.
The alignment of the particular sequence can be used to determine the property, structure, or evolutionary relationship of the particular gene.
The BLAST can be used for the alignment.
Needleman-Wunsch algorithm is used to understand the alignment of the molecules especially protein and nucleotides.
In this case, the two different proteins or molecules are compared by using the optimal alignment, and the sequence is then determined.
Thus, the correct answer is an option (C).
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Most eukaryotic cells contain mitochondria, but a few single-celled eukaryotic organisms found in oxygen-free environments do not. Which of the observations led biologists to reject the hypothesis that these mitochondria-free eukaryotes evolved before the endosymbiotic event that established mitochondria in other eukaryotes?
Answer:
Their nuclear genome contained relics of mitochondrial genes
Explanation:
Mitochondrion is a double membrane bound organelle that is found in most eukaryotic organism whose main function is to produce or generate energy. The mitochondria has DNA thus it is passed exclusively from mother to offspring.
It is hypothesized that it exists inside the cell after an endosymbiotic event
Since their nuclear genome contains relics of mitochondrial genes, biologists rejected the hypothesis that they evolved before the endosymbiotic event.
Herbicides are being used to kill weeds in a nearby field. The plants absorb the herbicides from the soil. Which organelle in the plant will most likely store the absorbed herbicide waste?a. ribosome.b. vacuole.c. chloroplast.d. mitochondrion.
Answer: The correct answer is Vacuole
Explanation:
The vacuole is an organelle found in the central portion of plant cells, and is usually filled with cell sap that acts as a "store house" for many substances entering into the cell.
Therefore, the herbicide waste absorbed by the plants will be stored in the VACUOLE.
Vacuole in the plant will most likely store the absorbed herbicide waste.
Vacuole is an important site for the degradation of cellular lipids, membrane-associated proteins, and cytoplasmic proteins
What is Vacuole?Vacuoles are organelles of plant, fungal, and algal cells. They are part of the internal membrane system and are separated from the rest of the cytoplasm by a membrane called the tonoplast .
The term “vacuole” means “empty space”. They help in the storage and disposal of various substances. They can store food or other nutrients required by a cell to survive. They also store waste products and prevent the entire cell from contamination.
The vacuoles in plant cells are larger than those in the animal cells and occupies more than 80% of the volume of the cell. It may be single or more in number.
Structure:
A vacuole is a membrane bound structure found in the cytoplasmic matrix of a cell.
The components of the vacuole, known as the cell sap, differ from that of the surrounding cytoplasm.
The membranes are composed of phospholipids and are embedded with proteins helping in transporting molecules across the membrane. Different combinations of these proteins help the vacuoles to hold different materials.
Vacuoles perform three specific types of functions:
- Storage:
It stores salts, minerals, pigments and proteins within the cells. The vacuole is also filled with protons from the cytosol helping in maintaining an acidic environment within the cell and a large number of lipids are also stored within the vacuoles.
- Turgor Pressure:
Vacuoles are filled with water exerting pressure on the cell wall called as Turgor Pressure providing shape and helping to withstand extreme conditions.
- Endocytosis and Exocytosis:
Substance entering through the vacuole is called as endocytosis and excreted through Exocytosis.
Vacuoles play crucial roles in
- cell expansion
- function as lytic organelles that contain digestive enzymes
Compounds contained within vacuoles also protect cells against environmental damage and deter attack by herbivores .
What are the other Cell Organelles?Ribosomes:
A ribosome is a complex molecular machine found inside the living cells that produce proteins from amino acids during a process called protein synthesis or translation.
Ribosomes also functions by binding to a messenger ribonucleic acid (mRNA) and decoding the information carried by the nucleotide sequence of the mRNA.
Chloroplast:
It is a cell organelle comes under the category of Plastids which are exclusively present in Plant cells.
These plastids are double-membraned cell organelles which play a primary role in the manufacturing and storing of food.
Types of plastids –
Chromoplasts- They are the color plastids, found in all flowers, fruits and are mainly responsible for their distinctive colors.
Chloroplasts- They are green coloured plastids, which comprise green-coloured pigments within the plant cell and are called chlorophyll.
Leucoplasts- They are colorless plastids and are mainly used for the storage of starch, lipids and proteins within the plant cell.
Mitochondrion:
Mitochondria are membrane-bound cell organelles that generate most of the chemical energy needed to power the cell's biochemical reactions. Chemical energy produced by the mitochondria is stored in a small molecule called adenosine triphosphate (ATP).
Thus it is also called as power house of the cell.
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Methane-producing archaeons in the rumens of cows and bioluminescent bacteria within the bodies of squid are both examples of _____, where organisms have "evolved together."
Answer:
coevolution
Explanation:
Coevolution is a form of evolution, which involves two or more species interacting together in which each species’ evolution causes a reciprocal effect on the evolution of the other through natural selection. Both species evolved together, thereby forming a kind of symbiotic relationship.
Methane-producing archaeons in the rumens of cows and the bioluminescent bacteria within the bodies of squid are examples of mutualistic relationships in coevolution that are formed as different organism species evolved together.
A scientist believes that she has found a new life form. Which of the following conditions is not considered essential in determining whether the putative new life form is alive?
a. The creature seems to react to being touched.
b. The creature possesses purposeful anatomical structures that differ from one another.
c. The creature's body is bilaterally symmetrical.
d. It appears to have cells when viewed under a microscope
Answer:
Answer is C, the creature's body is bilaterally symmetrical.
Explanation:
Note that , when an organism is said to be bilaterally symmetrical, it means that , the right side and the left side of the body plan are just like mirror image of each other, when cut or divided along a plane.
In this case, since the scientist just found a new life form, the type of symmetry possess by the organism is never to be considered essential, because if it were to be considered, it will mean the new organism will be terminated or killed to confirm the symmetry, which has automatically negate the process of determining whether the new life form is alive.
If protease treatment in Avery, MacLeod, and McCarty's experiment prevented the transformation of bacteria, what would have been the conclusion of these researchers?
Answer:
Protein is the genetic material; not DNA.
Explanation:
In Avery, MacLeod, and McCarty's experiment, digestion of proteins with the enzyme protease and use of this extract from the heat-killed S cell did not affect its ability to transform the R cell into the S cells. However, there was no transformation when the cellular extract of heat-killed S cells was treated with DNAse enzyme. They concluded that DNA was the genetic material responsible for transformation.
If protease treatment of cellular extracts of heat-killed S cell would have prevented the process of transformation, protein would have been concluded to be the genetic material.
A trait that confers a greater level of fitness, relative to those who lack it, is called a(n) ________.
Answer: Adaptation
Explanation:
The adaptation is the process by which a species becomes fitted to its environment which is a direct result of natural selection.
The traits that best suits the organism in an extreme conditions and helps in better survival is known as adaptation.
The variation in the species can be favored or rejected based on the condition. If the variation helps in survival of the organism in a better way then it is favored and if it is does not favors its survival then it is not carried further.
The best suited character is adapted and carried forward.
A scientist suspects that the food in an ecosystem may have been contaminated with radioactive nitrogen over a period of months. Which of the following substances could be examined for radioactivity to test the hypothesis?
a. the cell walls of plants growing in the ecosystem
b. the hair produced by humans living in the ecosystem
c. the sugars produced during photosynthesis by plants growing in the ecosystem
d. the cholesterol in the cell membranes of organisms living in the ecosystem
Answer: A and B
Explanation: The hair stores an amazing amount of nitrogen, so it makes sense that an increase above the normal concentrations contained in it would serve to detect abnormal levels of nitrogen in the environment, especially if it was radioactive, as it would also contain radioactive nitrogen. Contaminants have been
reported to affect cellular organelles and components such as cell membrane, which destabilizes the lipid bilayer conformation. Cells counteract this effect by reducing the nonbilayer phospholipid fraction to increase membrane stability this phenomenon can also be used in detecting contamination.
The following substances could be examined for radioactivity to test the hypothesis - B. the hair produced by humans living in the ecosystem.
The hair contains keratin which is a protein. Proteins are made up of amino acids that contain nitrogen in their structure that can be easily replaced by radioactive N.
the radioactive nitrogen will get incorporated into the newly forming proteins in the hair of humans. So, they can be tested for radioactivity. The cell wall is made up of cellulose which is a polymer of glucose and has no nitrogen in its structure Cholesterol is a type of lipid with a sterol nucleus. It has no nitrogen in its chemical structure The sugars produced during photosynthesis do not have any nitrogen in their structure. The structure of glucose can confirm this, therefore, they will not incorporate the radioactive nitrogen in themThus, The following substances could be examined for radioactivity to test the hypothesis - B. the hair produced by humans living in the ecosystem.
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The __________ nerve carries parasympathetic stimulation to the salivary glands, lacrimal gland, and the glands of the nasal cavity and palate.
Answer:
Facial nerve is your answer
A 1 ml sample of culture liquid contained 1000 viable bacterial cells. You serially diluted it twice, performing 10-fold or 1/10 dilutions into a final volume of 1 ml each time. As a result you have three tubes with 100, 10-1, or 10-2 of diluted culture. How many total cells are in the 1 ml of your 10-2 dilution tube?
Answer:
there are 10 viable bacterial cells in 1 ml in the 1/100 dilution tube
Explanation:
in 1ml there is 1000 viable bacterial cells → diluted with 9 ml of solvent (10 ml in total)→ 1000 viable bacterial cells in 10 ml (fist tube)
now we take 1 ml of the first tube into the second empty tube → has 1000/10 = 100 viable bacterial cells on 1 ml → diluted with 9 ml of solvent (10 ml in total)→ 100 viable bacterial cells in 10 ml (second tube)
then we take 1 ml of the second tube into the third empty tube → has 100/10 = 10 viable bacterial cells in 1 ml → diluted with 9 ml of solvent (10 ml in total)→ 10 viable bacterial cells in 10 ml (third tube)
therefore there are 10 viable bacterial cells in 1 ml in the 1/100 dilution tube
Frequently, important DNA regions with specific functions tend to contain short stretches of nucleotides that are conserved across different organisms (e.g., promoter sequence) and are recognized by specific proteins. What are these conserved sequences called?A. InitiatorsB. Critical elementsC. CodonsD. Repetitive sequencesE. Consensus sequences
Answer:
The correct answer is E. Consensus sequences
Explanation:
A consensus sequence are considered in nucleic acid and protein which is recognized by specific protein like RNA polymerase. In nucleic acid, these sequences are short nucleotide stretch which are conserved across different organism and reflects most common bases at each position in a segment alignment.
Example of a consensus sequence is promoter sequence. In bacteria, the promoter region contains two regions of consensus sequence characterized by -10 and -35 sequence. RNA polymerase recognizes this consensus sequence and binds to the promoter region. Therefore the correct answer is E.
In non-regenerating tissues or in extremely severe wounds, what is the main disadvantage of the scar tissue that replaces the lost tissue?
Answer:
It is unable to perform the functions of the lost tissue.
You are reading a blog written by a student who is working at an archeological dig in Cyprus. She mentions that they just uncovered an ancient burial site in which the skeletal remains of a human are found next to those of a cat. The arrangement of the bones suggests that the cat was buried with its owner and may have been a pet. Remarkably, the location of the grave relative to other known artifacts suggests it is 10,000 years old. If this is correct, then this is the earliest evidence for cat domestication. The blog author suggests that dendrochronological analysis of some of the wood fragments found nearby, together with C14 analysis should confirm the dates. You are not so sure these two methods will work equally well. Which method is most likely to shed accurate insight into the age of these two skeletons? Why?
Answer:
Obviously C-14 Method...
Explanation:
First things to clear first that the dendrochronological analysis is used only for plants that are alive. the second thing to under stand is that this analysis of a wood fragment would only give ages according to the size and number of rings present in the bark of wood.
The C-14 is a highly effective way because it can give aging analysis even for a million years or so and scientists used it everyday to predict the age by analyzing decayed organic carbon isotope C-14 present in every life form dead or alive on Earth.
The regulation of blood flow by local mechanisms within a capillary bed is called
Complete question:
The regulation of blood flow by local mechanisms within a capillary bed is called
A) autoregulation.
B) hormonal regulation.
C) hemoregulation.
D) vasoregulation.
E) neuroregulation.
Answer:
A) autoregulation.
Explanation:
Local changes regulate the flow of blood in each capillary bed. This occurs when the vasodilators trigger the local widening of arterioles and relaxation of precapillary sphincters to increase the blood flow into capillary networks. On the other hand, vasoconstrictors reduce blood flow. This ability of a tissue to control blood flow to meet its metabolic demands is called autoregulation.
For example, autoregulation increases the blood flow in the heart and skeletal muscle during physical activities to meet the increased demand for O2 and nutrients.
Autoregulation is the local regulation of blood flow in a capillary bed. This process lets tissues adjust their blood flow based on the body's needs, and involves mechanisms like the opening and closing of precapillary sphincters. Other systems like neural and endocrine mechanisms also help ensure adequate blood flow and perfusion.
Explanation:The regulation of blood flow by local mechanisms within a capillary bed is called autoregulation. This local, self-regulatory mechanism allows each region of tissue to adjust its blood flow, and thus its perfusion, based on the body's needs. These mechanisms are neither stimulated by the nervous system nor controlled by endocrine signals.
For instance, during strenuous exercise when oxygen levels decrease and carbon dioxide, hydrogen ion, and lactic acid levels increase, the capillary beds in skeletal muscle open, allowing more blood flow. This process is controlled by small muscles called precapillary sphincters. If these sphincters are open, the blood will flow into the associated branches of the capillary blood.
There are other homeostatic mechanisms in place to ensure adequate blood flow, blood pressure, and ultimately perfusion. These include neural, endocrine, and autoregulatory mechanisms.
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Which types of claims on food labels are strictly regulated by the Food and Drug Administration (FDA)? A. Nutrient claims and structure/function claims. B. Nutrient claims and health claims. C. Nutrient claims, health claims, and structure/function claims. D. Structure/function claims and health claims.
Answer:
Option-C
Explanation:
FDA or U.S Food and Drug Administration is a government agency which aims at protecting the public health by ensuring the efficacy, safety and security of food products, drugs and other medical devices, cosmetics.
The FDA regulations suggest that a food product must have three types of claims on it which are:
1. The health claim in which the relation between the food ingredient and health-related issues are mentioned.
2. The Nutrient claim which mentions the level of a nutrient in a food.
3. Structure/Function Claims which describe the role of nutrients on the human body.
Thus, Option-C is the correct answer.
The FDA is the government agency and the main role of these agency to protecting the health of the people by ensuring and check there will be no adulteration in the food .
As per the information given , the suitable answer will be claim of health , nutrient and structure claims.
Nutrient play very important part in our health as if our intake of nutrient is correct and healthy then our body will function correctly and it is the main duty of FDA to check and take all the precaution fo maintain the high standard of foods.
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Arrange the events in the stimulation of heart muscle in order from earliest (1) to latest (5). Note that this question does not list every step in the pathway, but the steps presented should be arranged in order.
Answer:
1) Pacemaker impulse generation.
2)AV node impulse conduction
3) AV bundle impulse conduction.
4) Bundle branches conduction.
5) Purkinjie fibres impulse conduction.
Explanation:
The cardiac conduction has following components.
1)SA node is the heart pacemaker in the right upper quadrant of heart. It generates electrical impulses and these impulses then move through atria and AV node to the Purkinjie fibres.
2) The impulses reach AV node. It controls heart rate. It serves as electrical relay station which slows the electrical current sent by SA node before the signals has passed to ventricles.
3) AV bundle is continuation is AV node and it transmits impulse from AV node to the Purkinjie fibres.
4) Electricle impulses from bundle of his passes through bundle branches (right and left ) to Purkinjie fibres.
5)Purkinjie fibres take the impulses from the bundle branches to the myocardium of ventricles.
Hox genes are thought to play an important role in the development of different morphologies because _____.
Answer: They provide positional information in the
An interneuron may receive multiple stimuli from the same sensory neuron over a very short period of time. The firing rate of the receiving neuron is proportional to the number of signals received from the sensory neuron over time.
Answer:
This is Temporal summation
Explanation:
The basic objective of temporal summation is to merge the amplitudes of individual pre- synaptic potential with the post synaptic potential. so that the sum amplitude of the potential produced can be greater than individual amplitudes. The merged amplitudes will enable the membrane potential to reach the threshold level for generation of post synaptic action potential.
Generally, the post synaptic membrane stores charges.Thus it stores in quick succession the amplitude of the first action potential, and as this is falling, it stores that of the second , third and fourth and merged this together to reach the threshold.
Temporal summation depends on the ''time frame' between the first and second pre-synaptic potential. Because the closer they are(pre-synsptic potential) the higher the chances of storing charges in the post-synaptic membrane for Post-synaptic potential. Thus if the duration is long, membrane potential of the post -synaptic neuron will be reduce, threshold will be be reached and PSP will not be achieved
In summary temporal summation depends on the time frame of the occurrence of post-synaptic potential.