The exception some diseases are not caused by microbes is not a verified exception in the use of Koch's postulates. Koch's postulates provide a framework for establishing a causative relationship between microbe and a disease.
The correct option is B
In general , Koch's postulate state that microbe must be found in all organisms suffering from the disease but not in healthy organisms. Cultured microbe should cause disease when introduced into a healthy organism also The microbe must be re-isolated from the inoculated, diseased experimental host and identified as being identical to the original causative agent.
Also, Koch's postulates remain an important tool for identifying the causative agent of infectious diseases, but there are limitations and exceptions to their use.
Hence , B is the correct option
To learn more about Koch's postulate , here
brainly.com/question/711971
#SPJ4
Explain how oberon and robin observing the athenian lovers is similar to the play the rude mechanicals will perform for theseus and hippolyta.
'Rude Mechanicals' isn't just a cool name for a band. In fact, the phrase refers to a specific group of characters in William Shakespeare's A Midsummer Night's Dream.
The obnoxious mechanicals are talented workers or artisans from Athens who desire to perform a play for the royals of the city. This group consists of six people.
Peter Quince, a carpenter, is the group's leader. Quince choose the play, allocates the roles, and oversees the acting during the rehearsal process. Also, he gives the prologue in the play that the obnoxious mechanicals do.
The next team member is Snug, a joiner who crafts cabinets, window frames, and doors. He is content to play the role of the lion because he describes himself as "slow of learning."
Learn more about William Shakespeare:
https://brainly.com/question/21004738
#SPJ4
the transcription factor creb is phosphorylated by a kinase in response to a signal the cell receives. the kinase hydrolyzes atp and transfers a phosphate group to creb. phospho-creb will bind specific dna sequences and activate transcription of target genes. therefore, target gene expression is low in the absence of a signal and high in the presence of the signal. what will happen to target gene expression if you add a non-hydrolyzable analog of atp to the cells?
When a non-hydrolyzable analog of ATP is added to the cells, it affects the target gene expression by inhibiting the kinase activity.
To learn more about : non-hydrolyzable
https://brainly.com/question/30634737
#SPJ11
The diagnostic term pyloric stenosis actually means ______.
condition of narrowing the gate keeper
Yes, that is correct. The diagnostic term pyloric stenosis actually means a condition of narrowing the gatekeeper, which refers to the narrowing of the pyloric sphincter muscle at the lower end of the stomach, leading to obstruction of the passage of food into the small intestine.
In this context, the "gatekeeper" refers to the pyloric sphincter, which is the muscular valve that controls the passage of food from the stomach to the small intestine. Pyloric stenosis results in a reduced opening, making it difficult for food to pass through and leading to various symptoms such as vomiting and weight loss.
Know more about pyloric stenosis - brainly.com/question/31357707
#SPJ11
Of the following choices, which are adaptations used by complex organisms (such as vertebrates or complex invertebrates) to allow gas exchange to occur in all body cells? select all that apply.
internal body fluids like blood & interstitial fluid
Flattened body shape
Very thin body walls.
specialized surfaces that are folded or branched
The adaptations used by vertebrates to allow gas exchange to occur in all body cells are:
A. Internal body fluids like blood & interstitial fluid
D. Specialized surfaces that are folded or branched.
Because they transport feasts to and from all cells, internal body fluids similar as blood and interstitial fluid are critical for gas exchange in complex organisms. The circulatory system distributes oxygen from the respiratory shells(e.g., lungs or gills) to the body's cells, while carbon dioxide( a waste product of cellular respiration) is transferred back to the respiratory shells for junking.
Hemoglobin is the oxygen- carrying patch in invertebrate blood, binding oxygen in the lungs and releasing it in the apkins. In complex organisms, folded or fanned shells are also essential for gas exchange. The lungs of mammals, for illustration, feature a complex network of airways.
Learn more about vertebrates at
https://brainly.com/question/19672046
#SPJ4
A starfish develops a new mutation that no other starfish in its population has; however, the mutation produces no change in how the starfish looks or functions. how does this starfish compare to the other starfish in its population?
If a starfish develops a new mutation that produces no change in how it looks or functions, then it is essentially the same as the other starfish in its population.
The mutation is considered a neutral mutation, meaning it does not provide an advantage or disadvantage to the starfish in its environment. Therefore, the starfish with the mutation is not necessarily "better" or "worse" than the other starfish in its population.
However, over time, if the environment changes, the mutation may become advantageous or disadvantageous. For example, if the starfish population is subjected to a new predator, the mutation may provide a survival advantage, leading to the increased frequency of the mutation in the population.
Conversely, if the mutation becomes disadvantageous, it may become less frequent or disappear from the population altogether.
For more such questions on mutation, click on:
https://brainly.com/question/14438201
#SPJ11
the figure shows how glucose homeostasis is maintained by two antagonistic hormones, insulin and glucagon. select the correct statement about these hormones.
Insulin and glucagon are two antagonistic hormones that are responsible for maintaining glucose homeostasis in the body.
Insulin is produced by the beta cells of the pancreas and promotes the uptake and storage of glucose in the liver and muscle cells. On the other hand, glucagon is produced by the alpha cells of the pancreas and stimulates the release of glucose from the liver into the bloodstream.
Both hormones work together to ensure that blood glucose levels remain within a normal range. Any imbalance between the two hormones can lead to hyperglycemia or hypoglycemia, which can cause serious health problems.
To know more about homeostasis, visit the link given below:
https://brainly.com/question/3888340
#SPJ4
In the prenatal nervous system, how many new nerve cells can be generated every minute?
The brain must expand throughout pregnancy at a rate of roughly 250,000 nerve cells per minute on average to reach the more than 100 billion neurons that make up a newborn baby's normal complement.
250,000 new neurons are added to the brain each minute at times during development. After birth, the brain continues to develop for a few years. When a child is about 2 years old, their brain has grown to about 80% of its adult size.A newborn's brain has 100 billion neurons, or about as many nerve cells as stars in the Milky Way, at birth. The brain creates trillions more "synapses" (connections between brain cells) and neurons than are required before birth.
To know more about nerve cells, click here:
https://brainly.com/question/15642720
#SPJ4
rank the five substrates from highest to lowest for fermentation. provide a possible explanation for these results. (refer to the introduction information for this lab.)rank explanation1.2.3.4.5.
Once you understand this, you can apply it to your lab results and rank the substrates accordingly.
Fermentation is a metabolic process in which an organism, usually microorganisms like yeast or bacteria, converts carbohydrates (such as sugars) into products like alcohol or acids. The efficiency of fermentation depends on the type of substrate used.
1. Glucose: Glucose is the most preferred substrate for fermentation because it is the simplest sugar and can be easily broken down by microorganisms.
2. Fructose: Fructose is another simple sugar that can be utilized by microorganisms for fermentation, but it may be less efficient than glucose due to differences in metabolic pathways.
3. Sucrose: Sucrose, a disaccharide composed of glucose and fructose, can be utilized for fermentation after being broken down into its monosaccharide components.
4. Starch: Starch is a polysaccharide composed of glucose units. It requires additional enzymes to break it down into glucose before it can be utilized for fermentation, which makes it a less efficient substrate.
5. Cellulose: Cellulose is a complex carbohydrate made of glucose units, but its structure makes it difficult for most microorganisms to break down and utilize for fermentation.
In general, the ease of breaking down the substrate and its accessibility to microorganisms can affect fermentation efficiency. Simple sugars like glucose and fructose are more easily fermented, while complex carbohydrates like starch and cellulose require additional steps and may not be suitable for all organisms. Based on your lab introduction information and the substrates you tested, you can rank them accordingly.
To know more about Glucose
brainly.com/question/30548064
#SPJ11
What two hormones of the thyroid and parathyroid are antagonistic?
The two hormones of the thyroid and parathyroid gland that are antagonistic are parathyroid hormone and calcitonin.
The parathyroid gland secretes a protein hormone called parathyroid hormone (PTH), which acts on the kidney, gut, and bones to regulate the amount of calcium in the serum. By preventing osteoclast activity in bones, the antagonist of parathyroid hormone (PTH), calcitonin, reduces blood calcium levels. Hence, both of these work negatively toward each other.
Calcitonin is a 32 amino acid peptide hormone that is released by chordates and parafollicular cells, often known as C cells, of the thyroid in humans. It works to counteract the effects of parathyroid hormone (PTH) by lowering blood calcium (Ca²⁺). A bigger prepropeptide produced by the CALC1 gene is cleaved by proteolytic enzymes to produce calcitonin.
To know more about parathyroid hormone, refer:
https://brainly.com/question/14745022
#SPJ4
which role does calmodulin play in the intracellular cascade triggered by Ca2+?
a. It modulates the strength of Ca2+ binding to its downstream targets.
b. It serves as a Ca2+ buffer.
c. It enhances downstream effects of Ca2+.
d. It binds to its downstream targets when activated by Ca2+.
e. It serves as a Ca2+ sensor when neurotransmitter is released.
D) It binds to its downstream targets when activated by Ca2+. Calmodulin plays a crucial role in the triggered by Ca2+ intracellular cascade by binding to and regulating various target proteins upon activation, thus modulating cellular processes such as signal transduction and enzyme activity.
Calmodulin plays a crucial role in the intracellular cascade triggered by Ca2+. It modulates the strength of Ca2+ binding to its downstream targets, enhances downstream effects of Ca2+, and binds to its downstream targets when activated by Ca2+. Additionally, calmodulin serves as a Ca2+ buffer, helping to regulate the intracellular concentration of Ca2+. However, it does not serve as a Ca2+ sensor when neurotransmitter is released.
Learn more about Calmodulin here:
https://brainly.com/question/31321222
#SPJ11
overproduction of hormones in which disorder leads to polyuria, hypercalcemia, hypertension, and kidney stones?
Primary Hyperparathyroidism is the disorder where overproduction of parathyroid hormone results in polyuria, hypercalcemia, hypertension, and kidney stones.
The disorder characterized by overproduction of hormones, leading to polyuria, hypercalcemia, hypertension, and kidney stones, is Primary Hyperparathyroidism.
Primary Hyperparathyroidism occurs when one or more of the parathyroid glands produce excessive amounts of parathyroid hormone (PTH). PTH is responsible for regulating calcium levels in the blood and bones.
1. Polyuria: Excess PTH causes an increase in calcium reabsorption in the kidneys, which results in increased urine production.
2. Hypercalcemia: As PTH levels rise, more calcium is released from the bones into the bloodstream, causing high levels of calcium in the blood.
3. Hypertension: High calcium levels can cause blood vessels to constrict, leading to increased blood pressure.
4. Kidney stones: The elevated calcium levels in the blood can lead to the formation of calcium-based kidney stones.
In summary, Primary Hyperparathyroidism is the disorder where overproduction of parathyroid hormone results in polyuria, hypercalcemia, hypertension, and kidney stones. It's essential to consult a healthcare professional for diagnosis and treatment of this condition to avoid potential complications.
To Learn More About Hyperparathyroidism
https://brainly.com/question/18153433
SPJ11
According to hard and soft acid base principle, a hard acid:A.has low charge densityB.shows preference for soft basesC.shows preference for donor atoms of low electronegativityD.is not polarizable
According to the hard and soft acid base principle, a hard acid is characterized by having a high electronegativity and a low polarizability. Therefore, option D is correct.
Additionally, a hard acid shows a preference for hard bases, which are those with high electronegativity and low polarizability. So, option B is incorrect. Furthermore, hard acids tend to interact with donor atoms of high electronegativity, which makes option C also incorrect. Finally, the charge density of a hard acid is not specifically mentioned in the definition of hard acids, so option A is also incorrect.
To know more about electronegativity click here:
brainly.com/question/17762711
#SPJ11
compared with a primate home range, a primate territory is: a. larger in size b. smaller in size c. not defended
d. actively defended
option B and D. Compared with a primate home range, a primate territory is smaller in size and actively defended. So, the answer is b. smaller in size and d. actively defended.
Compared with a primate home range, a primate territory is actively defended. A primate's home range refers to the area where it lives and moves around to find resources such as food, water, and shelter. On the other hand, a primate's territory is a smaller portion of the home range that is actively defended against intruders. Primate territories are typically defended by aggressive behaviors such as vocalizations, displays, and physical confrontations.
Learn more about home range here:
brainly.com/question/30166456
#SPJ11
What is the role of lac repressor on RNA polymerase?
The role of lac repressor on RNA polymerase is to regulate the expression of genes involved in lactose metabolism.
The lac repressor is a protein that binds to the operator region of the lac operon, preventing RNA polymerase from transcribing the genes required for RNA polymerase. In the absence of lactose, the lac repressor is active and inhibits the transcription of the genes. When lactose is present, it binds to the lac repressor, causing a conformational change that releases it from the operator region. This allows RNA polymerase to bind to the promoter region and initiate transcription of the genes necessary for lactose metabolism.
To know more about RNA polymerase click here:
https://brainly.com/question/29664942
#SPJ11
when doing bacterial inoculations it is usually better to pull microbes from the center of a colony to maximize growth. True or false
True. When performing bacterial inoculations, it is typically better to pull microbes from the center of a colony in order to maximize growth.
This is because the center of the colony is where the bacteria are most actively growing and reproducing, so taking samples from this area can increase the number of viable cells in the inoculum. Additionally, pulling from the center of the colony helps to ensure that the sample is representative of the entire colony, which can help to improve the accuracy and reproducibility of subsequent experiments.
To know more about bacterial inoculations click here:
https://brainly.com/question/30452324
#SPJ11
During the examination of the genitalia of a 70-year-old woman, a normal finding would be:a. Hypertrophy of the mons pubis.b. Increase in vaginal secretions.c. Thin and sparse pubic hair.d. Bladder prolapse.
Option c. Thin and sparse pubic hair is a normal finding during the genital examination of a 70-year-old woman.
During the assessment of the genitalia of a 70-year-elderly person, an ordinary tracking down would be slender and inadequate pubic hair. As ladies age, their chemical levels decline, which can cause changes in the presence of their genitalia. The mons pubis might diminish in size because of fat reallocation, and vaginal emissions might diminish because of hormonal changes.
Bladder prolapse, which is the plunge of the bladder into the vagina, is a typical condition in more seasoned ladies yet isn't viewed as an ordinary finding. Different changes that might happen with age incorporate vaginal dryness, diminished versatility of the vaginal walls, and an expanded gamble of urinary plot contaminations.
To learn more about genitalia, refer:
https://brainly.com/question/29607396
#SPJ4
Organic molecules are sometimes found within meteorites that crash into Earth. Which meteorite characteristic is similar to what most likely was present on early Earth? (1 point)
Group of answer choices
Abundance of oxygen
Very cold temperatures
Presence of inorganic molecules
Low levels of ultraviolet radiation
The characteristic of meteorites that is similar to what was likely present on early Earth is the presence of inorganic molecules. option(c)
Organic molecules are complex carbon-based compounds that are the building blocks of life, but they require inorganic molecules as precursors to form. On early Earth, the conditions were such that simple inorganic molecules could have combined to form complex organic molecules, which eventually gave rise to the first living organisms.
Similarly, meteorites that contain inorganic molecules, such as amino acids, nucleotides, and sugars, provide evidence that the building blocks of life may exist elsewhere in the universe, and could have contributed to the origin of life on Earth.
Learn more about Organic molecules
https://brainly.com/question/10504103
#SPJ4
A 68-year-old man presented to the emergency department with sudden onset of chest pain, left arm pain, dyspnea, and weakness while away from home on a business trip. His prior medical history is not available, but he admits to being a 2-pack per day smoker for longer than 20 years. Cardiac markers were performed at admission and 8 hours postadmission with the following results: CARDIAC 7:30 AM; 4:00 PM; MARKERS SEPTEMBER 26 SEPTEMBER 26 CK-MB (0–5 ng/L) 5.3 9.2 Myoglobin 76 124 (<70 μg/L) Troponin T < 0.1 1.3 (0–0.1 μg/L)
Questions 1. Do these results indicate a specific diagnosis? 2. If so, what is the diagnosis? 3. What myoglobin, CK-MB, and troponin T results would be expected if assayed at 4pm on september 27? 4. Can any assumptions be made about the patient's lifestyle/habits/health that would increase his risk for this condition? 5. are there any assays that might indicate his risk for further events of this type?
These are the results of specific diagnosis. This diagnosis is likely acute myocardial infarction (heart attack) due to elevated CK-MB, myoglobin, and troponin T levels.
1. Yes, these results indicate a specific diagnosis.
2. The diagnosis is likely an acute myocardial infarction (heart attack) due to elevated CK-MB, myoglobin, and troponin T levels.
3. If assayed at 4pm on September 27, myoglobin levels would likely have decreased, CK-MB levels might have peaked and started to decrease, and troponin T levels might still be elevated but could start to decrease in the next few days.
4. The patient's admitted history of smoking (2-pack per day for 20 years) increases his risk for developing cardiovascular diseases, including myocardial infarction.
5. To assess the risk for further events, additional assays may include lipid profile (cholesterol and triglycerides), C-reactive protein (CRP), and monitoring cardiac markers such as troponin T during follow-up visits.
To know more about diagnosis click here:
brainly.com/question/30451117
#SPJ11
In creating a transgenic plant created through the use of agrobacterium tumefaciens, researchers select plants that have tumors.a. Trueb. False
False. Agrobacterium tumefaciens is a bacterium commonly used in genetic engineering to introduce new genes into plants. This is achieved by inserting the desired gene into the bacterium's DNA, which is then introduced into the plant's genome when the bacterium infects the plant.
Researchers do not select plants with tumors in this process. Instead, they typically use tissue culture techniques to regenerate plants from cells that have been transformed by the bacterium. The transformed cells are selected using a marker gene, which allows researchers to identify which cells have taken up the desired gene. Once the transformed cells have been identified, they are grown into plants using tissue culture techniques.
Learn more about Agrobacterium tumefaciens
https://brainly.com/question/7231132
#SPJ4
flooding damages plants because oxygen deprivation leads to decreased cellular respiration. true or false
True. Flooding can lead to oxygen deprivation in plant roots, which can result in decreased cellular respiration and ultimately damage to the plant.
Plant roots require oxygen to carry out aerobic respiration, which is the process by which they generate energy from glucose. When the soil is flooded, the spaces between soil particles are filled with water, which can displace air and reduce the availability of oxygen to the roots. This oxygen deprivation can lead to a decrease in cellular respiration and a decrease in energy production. In addition to decreased cellular respiration, flooding can also lead to other harmful effects on plants, such as the accumulation of toxic metabolites, changes in soil pH, and the growth of anaerobic microorganisms. These effects can cause damage to plant tissues and reduce plant growth and productivity.
Learn more about cellular respiration here:
https://brainly.com/question/29771613
#SPJ11
how would the photosynthesis process be affected if chlorophyll a is blocked from absorbing light?
If chlorophyll a is blocked from absorbing light, the photosynthesis process would be significantly affected as chlorophyll is the main pigment responsible for capturing light energy in plants.
Without chlorophyll a, the plant would not be able to produce ATP (adenosine triphosphate) and NADPH (nicotinamide adenine dinucleotide phosphate) which are essential for the process of photosynthesis. As a result, the plant would not be able to convert carbon dioxide into glucose and oxygen, which are the end products of photosynthesis. This would ultimately lead to stunted growth and eventually, the death of the plant.
Energy in the form of ATP and NADPH. Without efficient light absorption by chlorophyll a, the energy required for the production of glucose and oxygen through photosynthesis would be reduced, leading to decreased plant growth and productivity
.
Learn more about chlorophyl here:
https://brainly.com/question/13500580
#SPJ11
Which of the following is not true of an antigen? It serves as a substrate for antibody production.�It serves as a substrate for antibody production, and its MHC-1 markers match host. It provokes an immune response. Its MHC-1 markers match the host.
The statement "Its MHC-1 markers match the host" is not true of an antigen. Antigens are substances that are recognized by the immune system and can provoke an immune response, leading to the production of antibodies.
Antigens do not necessarily match the host's MHC-1 markers, which are unique to each individual and are used to distinguish between self and non-self. In fact, the presence of foreign MHC-1 markers on an antigen can be an important factor in triggering an immune response against that antigen. Therefore, it is incorrect to say that an antigen's MHC-1 markers match the host.
To know more about Antigens click here:
brainly.com/question/27941474
#SPJ11
If a DNA template strand has a sequence of 3' TACAATGTAGCC 5', the RNA produced from it will be which sequence?
The RNA generated from this DNA template is denoted as AUGUUGUACGGU.
The RNA sequence that is generated from a DNA template strand is complementary and antiparallel to the DNA sequence. As a result, the RNA sequence would be 5' AUGUUGUACGGU 3', with the thymine (T) nucleotides substituted with uracil (U).
This process of RNA formation from DNA template is called transcription. This is the first stage in the gene expression. In gene expression the gene information is recorded and further it is made useful to make RNA molecules that makes the proteins ultimately.
The resulting RNA sequence is a single-stranded replica of the DNA coding strand, which is then employed during translation to synthesize proteins.
To know more about DNA transcription, visit,
https://brainly.com/question/1048150
#SPJ4
which term best describes all of the different species of insects living in a rainforest? group of answer choices a number of communities a niche a number of populations a habitat
The term that is best to describe all of the different species of insects living in a rainforest is "habitat".
A habitat is the natural environment in which an organism lives most of its lifetime, while an ecosystem is a community of living and non-living substances that interact with each other, for example, in a forest ecosystem, there are many different habitats, such as trees, streams, etc., and each of these habitats is home to different types of plants and animals, and they all interact with each other in the ecosystem.
The rainforest is a complex and diverse habitat that is home to countless species of insects, plants, animals, and other organisms, all of which are interconnected and dependent on each other for their survival.
To know more about the habitat refer here :
https://brainly.com/question/15125194#
#SPJ11
List all endocrine glands that are influenced by the anterior pituitary gland.
The endocrine glands influenced by the anterior pituitary gland include the thyroid gland, adrenal gland, gonads (ovaries and testes), and the mammary glands.
The anterior pituitary gland secretes various hormones that act on these endocrine glands to stimulate or inhibit their hormone production. For example, thyroid-stimulating hormone (TSH) released by the anterior pituitary gland stimulates the thyroid gland to produce thyroid hormones that regulate metabolism.
Adrenocorticotropic hormone (ACTH) stimulates the adrenal gland to produce cortisol, a hormone that regulates stress response and metabolism. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) stimulate the gonads to produce sex hormones like estrogen and testosterone.
Prolactin released by the anterior pituitary gland stimulates milk production in the mammary glands. The regulation of these endocrine glands by the anterior pituitary gland is an example of the complex interplay between different glands in the endocrine system.
To learn more about endocrine glands, here
https://brainly.com/question/11312688
#SPJ4
Which of these events would result in increased production of dilute urine? a. Refraining from drinking water for 48 hours b. Eating large amounts of salt c. Drinking large amounts of water Intake of nicotine
Drinking large amounts of water would result in increased production of dilute urine. When a person drinks more water than their body needs, the kidneys will excrete the excess water as urine. The correct option is C
This process is regulated by a hormone called antidiuretic hormone (ADH), which controls the amount of water reabsorbed by the kidneys. When there is excess water, the ADH levels decrease, leading to an increase in urine production.
Refraining from drinking water for 48 hours would result in decreased urine production and increased urine concentration. Eating large amounts of salt would also result in increased urine concentration, as the body tries to excrete the excess salt. Nicotine intake is not directly related to urine production and concentration, but it can cause dehydration, which would lead to decreased urine production and increased urine concentration.
Learn more about ADH
https://brainly.com/question/1552206
#SPJ4
Variables in photosynthesis (4 points) Suppose you think that heat is the most important energy variable in photosynthesis. Also, suppose you think that with more heat the less water will be oxidized by chloroplasts. Sketch a graph of what you think the relationship between the rate of water oxidation and the amount of heat would look like, g keep in mind which is the independent variable and which is the dependent variable, so you will put each on the correct axis. Label the axes accordingly. (2 points) iven your assumptions. When you make your sketch 2. Using the same equipment available to you in the oxidation of water lab, design an experiment to test your assumption about the relationship sketched above.
If we assume that heat is the most important energy variable in photosynthesis and that more heat leads to less water oxidation by chloroplasts, then we can sketch a graph of the relationship between the rate of water oxidation and the amount of heat.
The independent variable would be the amount of heat, which would be plotted on the x-axis. The dependent variable would be the rate of water oxidation, which would be plotted on the y-axis. The graph would show a negative correlation, with the rate of water oxidation decreasing as the amount of heat increases. To test this assumption, we could design an experiment where we expose chloroplasts to different temperatures and measure the rate of water oxidation. We could use a water oxidation assay and vary the temperature using a water bath. We could measure the absorbance of the solution at different time points to determine the rate of water oxidation. We could then compare the rate of water oxidation at different temperatures to see if there is a negative correlation between heat and water oxidation, as predicted by our assumption.
To know more about photosynthesis click here:
brainly.com/question/29775046
#SPJ11
Why don't tracheids and vessel elements contain nuclei or cytoplasm at functional maturity?
Tracheid's and vessel components go through controlled cell death when they reach functional maturity, losing their nuclei and cytoplasm in the process.
Plants use specialized cells called tracheid's and vessel components to transfer water. The xylem tissue, which is in charge of moving water and minerals from the roots to the rest of the plant, contains these cells.
It is believed that the absence of nuclei and cytoplasm is an adaptation that enables more effective water transfer. The cells can become more specialized for their role of conveying water by being stripped of their internal components, resulting in higher flow rates and less resistance.
Although these cells' ability to repair damage is constrained by the loss of their nuclei and cytoplasm, this trade-off makes it possible for them to carry water more effectively, which is essential for plant life.
Learn more about Tracheid's
https://brainly.com/question/15302827
#SPJ4
which of the following membranes would be the most fluid? a bilayer made of lipids with saturated 18-carbon fatty acids a bilayer made of lipids with monounsaturated 18-carbon fatty acids a bilayer made of lipids with saturated 16-carbon fatty acids a bilayer made of lipids with monounsaturated 16-carbon fatty acids all of the above are equivalent in fluidity.
The most fluid bilayer would be the one made of lipids with monounsaturated 18-carbon fatty acids.
The correct option is B.
In general ,Lipid bilayers are composed of phospholipids, which have a hydrophilic head and a hydrophobic tail. The fluidity of the membrane depends on the properties of the fatty acid tails in the phospholipids. Longer fatty acid tails tend to make the membrane less fluid, while shorter fatty acid tails tend to make the membrane more fluid.
Also , monounsaturated fatty acid has a kink in its tail, which prevents the phospholipids from packing closely together. This increases the space between the phospholipids, making the membrane more fluid.
Hence , B is the correct option
To learn more about monounsaturated fatty acid , here
brainly.com/question/28266821
#SPJ4
What is the approximate minimum length of an mRNA molecule that encodes a protein with a molecular weight of 30,000? (The average molecular weight of an amino acid is 110.)
a) 2475 nucleotides
b) 825 nucleotides
c) 550 nucleotides
d) 275 nucleotides
The approximate minimum length of an mRNA molecule that encodes a protein with a molecular weight of 30,000 is b) 825 nucleotides.
To calculate the minimum length of an mRNA molecule that encodes a protein with a molecular weight of 30,000, we need to divide the molecular weight of the protein by the average molecular weight of an amino acid. This will give us the number of amino acids in the protein.
30,000 / 110 = 272.73
So, the protein has approximately 273 amino acids. Since each amino acid is coded for by three nucleotides (codon), we need to multiply 273 by 3 to get the minimum number of nucleotides in the mRNA molecule.
273 x 3 = 819
Therefore, the approximate minimum length of an mRNA molecule that encodes a protein with a molecular weight of 30,000 is 819 nucleotides. The closest answer choice is b) 825 nucleotides.
Learn more about mRNA here: https://brainly.com/question/24885193
#SPJ11
