Answer: comparative anatomy
Explanation:Darwin proposed that the forelimbs of human, bats and other creatures (whale) are similar. Although these Fore limbs are used for different purposes; he reasoned that similar forelimbs must have the same origin(Anatomy). He therefore concluded that these organisms should share same ancestors for evolution of modern Organism forms. He reasoned further that these modifications in body structures are required adaptations for survival in the competitive environment –survival of the fittest.
Charles Darwin was an evolutionist, a biologist of immense knowledge. He formulated the law of survival of the fittest
The whale's pelvic girdle serves as evidence for common descent, showing that whales evolved from land mammals that had four legs. The presence of vestigial structures, such as undeveloped hind legs, along with fossil records showing land animal characteristics in aquatic mammals like Rodhocetus, supports the shared ancestry of whales and land mammals.
Explanation:The Pelvic Girdle as Evidence for Common Descent
The presence of a pelvic girdle in whales provides evidence for common descent, indicating that whales and land mammals share common ancestors. In land mammals, the pelvic girdle is a crucial structure that attaches the legs to the axial skeleton and is adapted for supporting body weight and facilitating locomotion. Whales, despite being aquatic and not needing legs for locomotion, have vestigial pelvic bones. These structures are remnants from their four-legged land mammal ancestors, implying that whales evolved from such land-dwelling creatures and secondarily lost their hind legs. In particular, vestigial structures like the undeveloped hind legs in baleen whales, labeled as 'c' in skeletal diagrams, further support this evolutionary link. Additionally, the fossil record shows evidence, such as the aquatic mammal Rodhocetus possessing a type of ankle bone unique to land animals, corroborating the evolutionary transition from land to sea.
Lymph found only when there is a pathological condition that allows it to leak from capillaries ____.
a. is excess interstitial fluid.
b. is filtered by the spleen.
c. is synthesized by the lymphoid organs.
d. All of the choices are correct.
Answer: All of the choices are correct.
Explanation:
Schamberg's disease is the pathological condition that allows lymph to leak from the blood capillaries, it causes no other symptoms beside skin discoloration and itching. The condition is caused by inflammation of capillaries near the surface of skin and subsequent leaking of blood cells into surrounding tissues.
So, the Lymph found in this patholgical condition is a fluid that circulates the entire body in the lymphatic system. The lymphoid organs include (the spleen, lymph nodes, bone marrow, thymus and lymph tissue) . These lymph nodes are small, bean-shaped structures which produce and store cells, specialized in fighting infections.
In the spleen (an organ in the upper left abdomen, filtration of these blood and disposal of worn-out blood cells occurs ), Hence, provides a reserve supply of blood.
However, Fluid in the spaces between the tissues are called interstitial fluid (tissue fluid). They provides the cells of the body with nutrients (via the blood supply) and a means of waste removal.
As such, Lymph is formed when the interstitial fluid is collected through tiny lymph capillaries, which are located throughout the body. It is then transported through lymph vessels to lymph nodes, which clean and filter it. Lymph then flows on to the lymphatic ducts, before emptying into the right or the left subclavian vein, where it mixes back with blood.
which best describes food when it reaches the stomacg
Answer:
The polysaccharides have been broken down.
Explanation:
The polysaccharides have been broken down in to monosaccharides by the process of hydrolysis to make them small particles which can be easily absorbed by the body .
What provides a link between the nervous system and the endocrine system?
Some characteristics of DNA are shared between all living organisms, whereas other characteristics of DNA differ between organisms. Classify DNA characteristics as either being a universal attribute of DNA or an attribute of DNA that is unique to particular individuals or species.
Explanation:
Universal: made up of nucleotides (A T C G), forms codons of three nucleotides, each encodes an amino acid
Species or Individual: size of the genome, sequence of DNA
The nucleus is a large membrane-bound organelle that houses the genetic information, DNA, in the cell. Sequences of DNA make up genes which can have different forms called alleles and comprise the genotype. DNA is transcribed into mRNA and later translated into amino acids which are linked together by rRNA to form proteins. These proteins, when expressed, are referred to as an organism's phenotype.
Further Explanation:
All the genetic information within the eukaryotic cell is stored within the nucleus as helical DNA. This DNA is tightly wound around histones as chromosomes. Chromosomes within the nucleus is unwound, unzipped and read by enzymes in a complex series of steps known as transcription. The message on DNA, called genes is copied by RNA polymerase, to form mRNA complementary sequence to that of the DNA strand. These are then translated into proteins in ribosomes.
Large chains of monomers form biological macromolecules which carry out many essential functions in the body these can include nucleic acids, carbohydrates, proteins and lipids. These are organic molecules, meaning they're ringed or long-chain Carbons bonded to the elements oxygen (O), hydrogen (H), nitrogen (N) and phosphorus (P).
Proteins are structural support molecules comprised of long chains of amino acids joined via peptide (CONH) bonds; these are 20 specific units that are arranged into several macromolecules. Amino acids are absorbed through digestion and are incorporated into the body’s cells to make up organs muscles signal molecules and an alternative energy source.
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Metabolic regulation
a. is the same thing as metabolic control.
b. is the maintenance of homeostasis at a molecular level.
c. always involves changing the amount of an enzyme in the cell.
d. maintains all reactions in a pathway near the equilibrium of each.
Answer:
d. maintains all reactions in a pathway near the equilibrium of each.
Explanation:
In living organisms, control processes similar to the control processes used in technology take place in a purely formal way, one can look at living beings as cyber machines. Governance and regulation are fundamental principles of the organization of the living. According to the type of signal or transmission of information, four different types of biological control processes are distinguished:
NeuralHormonal Differential gene expression in which substrate or substrate-like effectors are signaling agents. Feedback and forward control mechanisms in which the metabolites themselves act as direct signals to control their own degradation or their own synthesis.A black walnut (Juglans nigra) emits a chemical that may kill or inhibit the growth of other nearby shrubs or trees. However, the black walnut is unaffected by this interaction. This is an example of which symbiotic relationship?
Answer:
Amensalism
Explanation:
Amensalism is a form of relationship between organisms living in the same environment in which one is negatively affected, by inhibition or outright destruction, and the other is unaffected in any way.
Amensalism is of two types;
Competition: a relationship between two organisms which can be the same or different species in which one of the organisms deprive the other the necessary resources to survive in the environment, leading to inhibited growth or destruction.Antibiosis: A relationship between organisms of different species in which one produce chemicals that kills or inhibits the growth of the other.Hence, the relationship between black walnut and nearby shrubs or trees is antibiosis, a form of amensalism.
The black walnut's release of growth-inhibiting chemicals is an example of allelopathy, which is a type of amensalism where one species is negatively affected and the other is unaffected.
The chemical inhibition of growth or death of nearby trees and shrubs by a black walnut (Juglans nigra) through the secretion of chemicals is an example of allelopathy, which is a type of interference interaction. This phenomenon occurs when allelopathic plants like the black walnut exude chemicals from their roots that inhibit the growth of surrounding plants. Given that the black walnut isn't affected by these chemicals, the relationship can be characterized as amensalism, where one species is harmed while the other remains unaffected. It's different from commensalism, where one species benefits and the other is neither harmed nor benefited, and mutualism, where both species benefit.
Muscle cells and nerve cells in one species of animal owe their differences in structure to
Answer: Different genes being expressed.
Explanation:
The differences in the structure of the muscle and the nerve cells is due to the gene expression or gene expressed in the cell and the gene silenced to achieve the desired organisation of cells.
Which of the following is true about tubular reabsorption?
A) It always happens via the paracellular route.
B) It moves water and solute from the blood to the filtrate.
C) It always involves active transport.
D) It involves carrier-mediated transport.
Answer: D (It involves carrier-mediated transport).
Explanation:
Tubular reabsorption transports nutrients back into the blood. Tubular reabsorption of nutrients such as sodium, glucose, lactate amino acids, and other organic substances occurs via carrier membrane proteins to the proximal tubule.
Most of the substances that are reabsorbed via the proximal tubule require the use of carrier membrane proteins, for facilitated diffusion, active transport and secondary active transport.
Example of secondary active transport is the sodium-dependent glucose cotranspoter.
Out of the provided options, tubular reabsorption mainly involves carrier-mediated transport. This process helps in moving solute and water from the filtrate back to the blood. It does not always use the paracellular route or involve active transport.
Explanation:The statement 'D) It involves carrier-mediated transport' is the most accurate of the options provided. Tubular reabsorption, a critical component of the nephron's function in our kidneys, is a process by which solutes and water are removed from the tubular fluid and transported back into the blood. Ironically, this process doesn't always occur via the paracellular route or always involve active transport. The process often involves carrier-mediated transport, where specific molecules (the 'carriers') help move substances across cell membranes - this aids the reabsorption of water and various solutes back into the blood from the filtrate.
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Explain how aggregation is likely to result in a greater likelihood of survival for schooling fish in the presence of a predator.
Answer:
Aggregation is a mechanism developed by a group of fish called shoal that stay together for social functions. Schooling in shoal is an aggregation technique whereby shoaling fish swim together in a coordinated manner in the same direction. Defense against predators is one of the benefits derived from aggregation which increases the chance of survival of schooling fish. This helps in detecting predators and in reducing the chance of individual capture.
For example, schooling fish that are of the same size and silvery in appearance, through aggregation, would make it difficult for a predator that is visually oriented to pick an individual out of the group as a result of “confusion effect” created by the schooling fish.
Aggregation in schooling fish also helps the group to easily scan for predators around as there are bound to be “many eyes” on the look out for predators. This helps in reducing the chance of predatory attack on the group and increasing the chance of survival of schooling fish.
The larger the number of the schooling fish in aggregation, the higher the chance of survival against predators.
Aggregation or schooling in fish is a survival strategy where forming a group confuses predators and dilutes the risk of predation for individual fish. In addition, a larger school offers greater genetic variation which is essential for the survival of future generations.
Explanation:Aggregation or schooling behavior in fish is a classic example of defensive behavior in biology where individuals come together to form a group, making it difficult for predators to single out and target any one individual. When a predator approaches a school of fish, the school acts as a single entity and performs evasive maneuvers. The predator, confronted with the appearance of a larger creature or a confusing mass of individuals, often hesitates while trying to select a target, giving the fish an opportunity to escape.
The increase in a school's size, or aggregation, provides better protection by diluting the risk of predation. This phenomenon, known as the 'confusion effect', has provided survival benefits to prey species and has been a driving force behind its evolution. To put it another way, it's harder to catch one individual in a large moving group than it is to catch a lone individual.
Aggregation also has the effect of genetic variation in the school of fish. The larger and more diverse the school, the richer the genetic pool, which is fundamental to the survival of future fish generations. This factors in the ability to adapt to environmental changes, including the presence of predators.
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A population of animals is split in half by a river or speciation is completed at the two has a joint when you grout causes the river to run dry how would this impact the two populations
Due to huge effect use of Drought the population of animal get extinct.
Explanation:
Droughts can have a severe impact on the extinction of animal populations, specifically in Arid and Semi environments. Different type of climate changes can accelerate the dying of particular species or animal population.
For extinction of population and also species Droughts play vital role. Droughts are one of such severe climatic change that leads to the extinction of species. Some life traits of specific Species make it vulnerable to drought.
Answer:
Individuals could now freely mate, and gene flow would increase
Explanation:
During evolution of the myosin superfamily different myosins diverged in such a way that each is adapted to the specific task that it carries out. In lecture we discussed three properties of myosin motors that vary among family members that underwent adaptation. What are those properties?
Answer:
Three properties of myosin motors are a step size, duty ratio, and tail interactions.
Explanation:
Myosin is an actin motor protein. The primary function of the myosin is to convert ATP to energy. Duty is the fraction of ATP cycle to actin. Step size means displacement during 1 ATP cycle. Step size of myosin was found out by measuring the velocity of different filament size of myosis. Muscles contraction, chemo taxis, cytokinesis is some function that can be related with among the family.What is a second messenger?
A. A substance that reacts with a first messenger.
B. A small substance generated in response to receptor binding that activate or inactivate specific proteins.
C. A substance that reacts with a hormone or other ligand
D. A substance released into the intracellular space.
Answer:
The correct answer is B. A small substance generated in response to receptor binding that activate or inactivate specific proteins.
Explanation:
An example of second messengers are AMPcyclic, Ca2 + ion. In the case of cAMP, the enzyme adenylate cyclase is synthesized from ATP (this is found within the cell membrane). The AMPC is involved in cell signal transduction pathways before external and / or internal stimuli, (example: adrenaline hormone), being able to activate the enzyme called protein kinase A (PKA), which phosphorylates its target and thus the signal is transmitted.
Parents with the dominant phenotype cannot have offspring with the recessive phenotype.
Answer:
False, they can have recessive phenotype
Explanation:
A phenotype is a viable characteristic an individual presents as a consequence of the interaction between its environment and its genotype.
This doesn’t necessarily means that the individual’s aleles are both dominant (homozygotes), they could have one dominant and one recessive gen (heterozygotes), meaning that, if the another parent is homozygote with both recessive aleles the offspring could heritage homozygote recessive aleles that will result in a recessive phenotype.
You can observe in the image I added a punnet square that exemplifies the scenario. You can see that the offspring has 1/2 probability to have recessive phenotype.
I hope you find this information useful and interesting! Good luck!
Answer:
75% and 25%
Explanation:
For a science fair project, two students decided to repeat the Hershey and Chase experiment, with modifications. They decided to label nitrogen of the DNA, rather than the phosphate. They reasoned that each nucleotide has only one phosphate and two to five nitrogens. Thus, labeling nitrogens would provide a stronger signal than labeling phosphate Why won't this work?A) There is no radioactive isotope of nitrogen.B) Radioactive nitrogen has a half-life of 100,000 years, and the material would be too dangerous for too long.C) Avery, MacCloud and McCarty already did this.D) Although their are more nitrogens in a nucletotide, labeled phosphates actually have 16 extra neutrons; t Shift Ctrl herefore, they are more radioactive.E) Amino acids (and thus and proteins proteins
Final answer:
Labeling nitrogen instead of phosphate in DNA would not work because radioactive nitrogen is not practically detectable like phosphorus-32 used in the Hershey and Chase experiment, and nitrogen does not exclusively mark DNA over proteins.
Explanation:
The idea for the student's science fair project is based on modifying the Hershey and Chase experiment, by labeling the nitrogen atoms in DNA instead of phosphate to provide a stronger signal. However, labeling nitrogen would not provide the desired outcome for several reasons. First and foremost, there is a radioactive isotope of nitrogen (¹⁵N), as demonstrated by Meselson and Stahl's experiment, but it is not used because its radiation is not detectable by the same means used for phosphorus-32. In the Hershey and Chase experiment, radioactive phosphorus (³²P) was used to label DNA because phosphorus is a component of DNA but not protein, and its radioactivity can be easily detected. Secondly, using ¹⁵N would not differentiate between DNA and protein because amino acids also contain nitrogen atoms.
Suggest two ways that reflex reactions help maintain homeostasis in the human body.
Answer:
1. Sweat makes the body cool off in the heat
2. Shivering in the cold
Explanation:
sweat is a reflex that the body makes to maintain homeostasis. the purpose is to make the human body cooler as if it was water produced by the body. On the other hand, shivering in the cold produced heat made by body movement.
Reflex reactions, driven by the autonomic nervous system, play a vital role in homeostasis by ensuring balance in bodily functions. These reactions can regulate heart rate and body temperature depending on the body’s needs, maintaining equilibrium and promoting health.
Explanation:
Reflex reactions play a vital role in maintaining homeostasis in the human body, which is the maintenance of equilibrium around a specific set point in the body. Reflex reactions are driven primarily by the autonomic nervous system, which has two divisions, the sympathetic and parasympathetic systems, that often effect change in opposing directions thereby ensuring balance within the body's systems.
One example of this is in the regulation of heart rate. The sympathetic system increases heart rate when the body needs to respond to a stimulus such as emotional stress or physical exertion, whereas the parasympathetic system decreases heart rate when the body is at rest, helping to conserve energy and facilitate recovery. This balance helps maintain a consistent heart rate that is appropriate for the body's current needs and conditions.
Another example is the role these systems play in regulating body temperature, an important aspect of homeostasis. If the body becomes too warm, for instance, the sympathetic system triggers a reflex response to promote heat loss through processes such as sweating and dilation (widening) of blood vessels in the skin. If the body is too cold, the sympathetic system will trigger reflex responses to conserve heat, such as causing goosebumps and reducing blood flow to the skin. These reflexes help maintain a consistent body temperature, even when external conditions change.
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Which of the following requires eIFs for initiation? Which of the following requires eIFs for initiation? eukaryotic translation prokaryotic translation post-translational modification chaperonin activity eukaryotic transcription
Answer:
Eukaryotic translation.
Explanation:
Translation is the process of the formation of the proteins from the RNA molecules with the help of different enzymes and proteins. Translation is quite different in case of prokaryotes and eukaryotes.
The initiation in case of eukaryotes requires different enzymes and translation factors. eIFs are the initiation factors that contains proteins and required for the initiation of eukaryotes translation. eIF1 and eIF1A are the proteins binds with the 40'S ribosome subunit of eukaryotes.
Thus, the correct answer is option (1).
Several hormones are synthesized in the hypothalamus and transported to the anterior pituitary gland. The mechanism of transportation from the hypothalamus to the anterior pituitary gland is through the ________.
Answer:
Hypothalamic-hypophyseal portal veins (a network of blood vessels)
Explanation:
The hypothalamus- pituitary secretory complex can be referred to as the "command center" of the endocrine system. This is because the complex regulates the synthesis and secretion of hormones by other glands.
The anterior pituitary secretes a battery of hormones that collectively influence virtually all physiological responses in the body. This function makes the pituitary gland be referred to as the"master gland" of the body. This is true but the hypothalamus is responsible for regulating the synthesis of these hormones by the pituitary. Some neurons in the hypothalamus secrete hormones that controls the secretion of hormones by the anterior pituitary. These hypothalamic hormones are referred to as releasing and inhibiting hormones depending on whether they stimulate or inhibit secretion of hormones by the anterior pituitary.
The hypothalamus releasing/inhibiting hormone are carried directly to the anterior pituitary through a network of blood vessels in the infundibulum called hypothalamic-hypophyseal portal veins.
Specific hypothalamic hormones bind to receptors on specific anterior pituitary cells, thereby regulating the release/inhibition of the hormone they produce.
The mechanism of transportation from the hypothalamus to the anterior pituitary gland is through the hypophyseal portal system, a network of blood vessels.
Explanation:The transport of hormones from the hypothalamus to the anterior pituitary gland is through the hypophyseal portal system. This system is a network of blood vessels that allows for direct transport between these two glands. The hypothalamus secretes releasing and inhibiting hormones into this portal system which travels down to the anterior pituitary triggering or preventing the release of certain hormones respectively.
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Which statement regarding cholesterol is false? It is the precursor for steroid hormones. It is not usually a component of eukaryotic membranes. It is the precursor for bile acids. It has a hydrophilic functional group.
Answer:
It is not usually a component of eukaryotic membranes.
Explanation:
Cholesterol is responsible for modulating the fluidity of the cell membranes of eukaryotes.
It is produced in most animal cells, and its formation is substantially active in liver cells, where bile acids are synthesized from cholesterol.
In addition, cholesterol is the precursor of steroid hormones such as progesterone, testosterone, estradiol and cortisol.
Cholesterol (like other lipids) is amphipathic, meaning it has a polar head (hydrophilic) and an apolar tail (hydrophobic).
Given the above, it can be concluded that the false statement is "it is not usually a component of eukaryotic membranes".
Gail Lewis is a 48-year-old woman who has worked as a legal secretary for a high-powered defense attorney for the last 12 years. She has never been married, and she lives alone. She has been experiencing a burning sensation in her stomach for the last few months, which is now worsening. Gail finally makes an appointment with her healthcare provider (HCP) to find out what is causing the stomach pain.
Which information is most significant when assessing a client suspected of having a peptic ulcer?
Answer: The person`s use of Aspirin
Explanation:
Gail has been experiencing a burning sensation in her stomach for the last few months.This symptom is most significant information to ask her if she has frequently been using Aspirin or products containing aspirin. Gail´s hearburn can be caused by Aspirin which is known to stress the lining of the stomach.
The most significant information for diagnosing a peptic ulcer is the abdominal pain description, the potential presence of Helicobacter pylori, and the patient's NSAID use. Endoscopic examination and H. pylori testing are essential for a definitive diagnosis.
Explanation:The most significant information when assessing a client suspected of having a peptic ulcer is the detailed description of the abdominal pain, its pattern, relation to meals, and any accompanying symptoms such as belching, vomiting, weight loss, and poor appetite. In Gail Lewis's case, a burning sensation worsening over a few months is a key symptom. It is also crucial to consider the possible presence of Helicobacter pylori, a bacterium strongly associated with the development of peptic ulcers. Additional factors to consider include the patient's use of nonsteroidal anti-inflammatory drugs (NSAIDs), as these can contribute to ulcer formation.
Confirmation of a peptic ulcer typically requires an endoscopic examination, which allows direct visualization of the ulcer, and confirmation of H. pylori infection which may necessitate an antibiotic treatment, along with acid-reducing medication.
How does a gastrovascular cavity differ from an alimentary canal? The gastrovascular cavity __________.
a. absorbs food molecules but does not produce digestive
b. enzymes has only a single opening
c. stores food but does not digest
d. it is the location for extracellular digestion
Answer:
The answer is C.
Explanation:
describe the polymerase chain reaction using an analogy
Answer:
Polymerase chain reaction (PCR) is a common laboratory technique used to make many copies (millions or billions!) of a particular region of DNA. This DNA region can be anything the experimenter is interested in. For example, it might be a gene whose function a researcher wants to understand, or a genetic marker used by forensic scientists to match crime scene DNA with suspects.
Explanation:
i hope this answers your question
Polymerase Chain Reaction (PCR) can be analogized to a high-speed copy machine. It systematically heats and cools DNA to create strands that are then duplicated by the enzyme Taq polymerase. It's essentially ‘copying’ a specific DNA sequence again and again.
Explanation:The Polymerase Chain Reaction (PCR) can be compared to a replication machine that quickly duplicates a specific section of DNA. Its three-step cycle (denaturation, annealing, and DNA synthesis) mimics copying a selected text, highlighting it (to mark where copying starts and ends), and then pressing a 'copy' button that replicates the highlighted text each time it is pressed. The result is multiple copies of that specific portion.
At the beginning, the DNA molecule is heated to high temperatures to denature or separate the two strands, like tearing a book into two halves so that the text (information) can be accessed. Next, the temperature is lowered which allows the primers (short pieces of DNA that matches the start and end point of the region to be copied) to attach to each DNA strand, like using highlighters to mark the beginning and end of the text in the book that needs to be copied. Lastly, the Taq polymerase, isolated from the Thermus aquaticus bacteria (akin to a high-temperature resistant copy machine), synthesises new strands of DNA from the original strands, duplicating the 'highlighted text' over and over.
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Nina was almost hit by a bus. However, she is okay and her parasympathetic system is responding accordingly. It is: Please choose the correct answer from the following choices, and then select the submit answer button. a) slowing her heart rate and activating her digestion. b) contracting her pupils and increasing respiration. c) slowing her heart rate and inhibiting her digestion. d) contracting her pupils and increasing secretion of stress hormones.
Final answer:
The parasympathetic nervous system response after a stressful event like almost being hit by a bus is to slow down Nina's heart rate and activate her digestion, returning her body to a state of calmness and homeostasis.So,option a) slowing her heart rate and activating her digestion is correct.
Explanation:
After Nina was almost hit by a bus, her parasympathetic nervous system is responding to calm her body down from the stressful event. The correct response of her parasympathetic nervous system would be a) slowing her heart rate and activating her digestion. This is because the parasympathetic system is responsible for the 'rest and digest' state, which involves lowering the heart rate, reducing blood flow to the skeletal muscles, and stimulating the digestive processes after a fight-or-flight response has occurred. In this instance, it helps Nina to recover by bringing her body functions back to a state of internal homeostasis.
Azotobacter is a genus of bacteria that live in soil and have the following characteristics: a. They are bacilli. b. They are gram-negative. c. They are obligate aerobes. d. They can fix nitrogen. (Unlike some other nitrogen-fixing bacteria, which associate with the roots of plants, Azotobacter species are free-living.)
Answer:
The correct answer will be- all options are correct.
Explanation:
Azotobacter is a genus or a group of bacteria which are involved in the process of nitrogen fixation.
The bacteria can be easily identified by their rod-shaped form and gram staining. Gram staining results show that they are gram-negative bacteria as they stain pink in color due to the thin peptidoglycan layer.
They require oxygen to perform cellular respiration so are called obligate aerobes. Also, they can fix the atmospheric nitrogen by converting it into ammonia.
Thus, all the options are correct.
Terrestrial organisms lose water through evaporation. In what ecosystem might an entomologist find a good study organism to examine the prevention of water loss? mastering biology
Answer:
The correct answer is desert.
Explanation:
If an entomologist wants to look for a good example of an organism that prevents water loss, he must look for organisms in the desert.
A desert is one of the ecosystems that receives less water, the rainwater that falls is less than 150 mm per year.
Despite the heat and lack of water, there is a wide variety of living beings that inhabit this type of ecosystem. But for that they must save water, and they do this through adaptations that they developed when they were living in this place.
They can have two types of adaptations: physical or behavioral adaptations.
In behavioral adaptations, desert animals simply avoid the sun to generate greater water retention. Depending on the species, some choose to go out only during the night, and others prefer to be under the shadow of a cactus.
Some species also get the water they need through the food they eat, which prevents them from having to go in search of water.
One type of physical adaptation is the one that occurs in those animals who accumulate fatty tissue in their body which allows them to stay fresh and thus prevent water from evaporating.
Wheat production W in a given year depends on the average temperature T and the annual rainfall R. Scientists estimate that the average temperature is rising at a rate of 0.15°C/year and rainfall is decreasing at a rate of 0.1 cm/year. They also estimate that, at current production levels, δW/δT = -2 and δW/δR = 8. Estimate the current rate of change of wheat production, dW/dt.
Answer:
-1.1
Explanation:
Data provided in the question:
Average temperature is rising at a rate, [tex]\frac{dT}{dt}[/tex] = 0.15°C/year
Rate of change rainfall, [tex]\frac{dR}{dt}[/tex] = - 0.1 cm/year
[tex]\frac{\delta W}{\delta T}[/tex] = -2
[tex]\frac{\delta W}{\delta R}[/tex] = 8
Now,
we need to calculate [tex]\frac{dW}{dt}[/tex]
since,
The wheat production (W) is dependent on the rainfall (R) and the Temperature (T)
thus, Using the chain rule , we have
[tex]\frac{dW}{dt}[/tex] = [tex]\frac{\delta W}{dT}\times\frac{dT}{dt}[/tex] + [tex]\frac{\delta W}{dR}\times\frac{dR}{dt}[/tex]
on substituting the respective values, we get
[tex]\frac{dW}{dt}[/tex] = -2 × 0.15 + 8 × (-0.1)
or
[tex]\frac{dW}{dt}[/tex] = -0.3 - 0.8
or
[tex]\frac{dW}{dt}[/tex] = -1.1
G6PD deficiency is an X-linked recessive disorder. When people who have this disorder eat fava beans, they have a dangerous acute reaction in which a large number of their red blood cells rupture. A mother has the disorder; the father does not. What is the chance that any child of this union will have the trait?
Answer:
In case mother carries an X-linked recessive disease and father does not, the risk for each offspring is dependable upon the offspring is male or female. In case of male child, there is a 50% chance to be disease free, and a 50% chance to be affected by this disorder.
Explanation:
G6PD deficiency is an X-linked recessive disorder. The coding gene for G6PD is in the distal long-arm of the X chromosome (Xq28). The gene is 18 kb of length. It has 13 exons. The G6PD enzyme consists of 515 amino acids.
There are over 60 mutations detected in the G6PD gene. The majority of them are single-base changes (amino acid substitution). The X-linked disease is a disease caused by mutation of a gene on the X chromosome. In X recessive disorder male children most commonly manifest the abnormality. The female children are carriers and asymptomatic in case of homozygous or if there is an inactivation of their normal X chromosome.
In case mother carries an X-linked recessive disease and father does not, the risk for each offspring is dependable upon the offspring is male or female. In case of male child, there is a 50% chance to be disease free, and a 50% chance to be affected by this disorder.
In case of a female offspring, there is a 50% chance to be unaffected, and a 50% to be a carrier.
If a father has G6PD deficiency, while the mother is a carrier all male offspring will be healthy. In this case, the female offspring will be carriers.
In case of G6PD deficiency, reactive oxygen molecules accumulate and lead to the damage of red blood cells. Certain factors (fava beans, certain medicaments, infections etc. ) may lower the reactive oxygen molecules and lead to acute episodic hemolytic anemia. In that case, red blood cells are damaged faster than they may be replaced in the human body. There are signs of hemolytic anemia in case of G6PD deficiency. Thus, chronic hemolysis may occur with a significantly lower level of enzyme. In case of symptomatic patients there is a neonatal jaundice and acute hemolytic anemia. Kernicterus may be a neonatal complications in G6PD deficiency.
What are the reasons for the several day delay in a primary response. Infection______. A. transport to secondary lymphoid tissue B. antigen processing and presentation C. small initial # of lymphocytes specific for the antigen D. proliferation and differentiation.
Answer:
The correct answer is D. proliferation and differentiation.
Explanation:
Primary immune response occurs due to the first exposure of an antigen to the immune system. The primary immune response is generally delayed by many days because it takes time for B and T cells to become cloned and to proliferate and differentiate.
Then after several days of proliferation and differentiation of activated T and B cells, T cells become effector T cells and B cell becomes plasma cells which then eliminates the antigen. Memory B and T cells are also produced during this process which helps in generating a quick immune response during the second and subsequent exposure of that antigen.
So the correct answer is D. proliferation and differentiation.
What class of barrier to gene flow would we be observing if we noted that the offspring of a lion and a tiger (two different species) are awkward, gangly beasts that have poor survival in the wild?
a. Premating barrier
b. Geographic isolation
c. Prezygotic barrier
d. Temporal isolation
e. Postzygotic barrier
Answer:
The correct answer is e. Postzygotic barrier.
Explanation:
Different species can not mate and produce viable, healthy and fertile descendence, due to certain mechanisms of reproductive isolation.
These mechanisms involve different kinds of barriers that make it difficult for two different species to produce viable and fertile progeny.
One of these is the postzygotic barrier, which avoids the hybrid zygote to develope to adultness. In these situations, there is a mix of chromosomes that can not happen to meet or that they lack information.
There are cases in which the embryo dies, but some times the individual can reach some more advanced develope stages. If this is the case, in general, they can not survive because the organism is unhealthy. And if they reach adultness in good sate they can not leave descendence, as they are sterile.
Activities such as amino acid synthesis and active transport in plant cells are powered by _____.
a. the light reactions and carbon fixation reactions of photosynthesis.
b. ATP from the light reactions of photosynthesis.
c. ATP from alcoholic fermentation.
d. ATP from glycolysis and cellular respiration.
e. ATP from lactic acid fermentation
Answer:
The correct answer will be option-D
Explanation:
In-plant cells, ATP is synthesized during photosynthesis and cellular respiration. The ATP molecule formed during photosynthesis is utilized during the synthesis of sugar molecule during the Calvin cycle.
The ATP which are synthesised during the cellular respiration is higher in number as compared to photosynthesis. In cellular respiration, the ATP is synthesised during the glycolysis and electron transport chain which accounts for 34 to 36 ATP molecules.
These ATP molecules are utilized to perform other metabolic functions like amino acid synthesis and active transport.
Thus, option-D is the correct answer.
Describe the path of a nerve impulse in a neuron starting with the dendrite
The electrical charge travel through the neural cell membrane and thus generates a nerve impulse. The nerve impulse travels through membrane of neural cell by the movement of ions across the membrane. The nerve impulse signal will travel through the neuron and reaches at the end of a neuron that is axon terminal. The end (axon) of a neuron connects with the dendrites of second neuron with the help of molecules known as neurotransmitters. This connection between two neurons that allows the nerve impulse to travel is called synapse.
Learn more: Nerve impulse
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A nerve impulse in a neuron starts at the dendrite and then passively moves to the cell body. A structure in the cell body, called the axon hillock, integrates these signals which are then propagated down the axon. The impulse triggers neurotransmitters at the synapse that stimulate the next neuron or target.
Explanation:The path of a nerve impulse in a neuron starts with the dendrite, which functions as the contact point for incoming signals from other neurons or sensory cells. The signal then passively travels to the cell body, where specialized structures integrate the signals. This integration of signals occurs at the axon hillock, which serves as a junction between the cell body and the axon.
The axon is a tube-like structure that helps propagate the integrated signal towards the axon terminals. These terminals are further responsible for synapsing on other neurons, muscle, or target organs, which in turn allow communication of signals to these other cells. Some neurons also carry with them insulating layers known as myelin sheaths to speed up signal conduction and minimize dissipation. These insulating sheaths contain gaps known as nodes of Ranvier where the signal is 'recharged' as it travels along the axon.
This conduction ends when enough neurotransmitters are released at the synapse, the gap between neurons, to stimulate the next neuron or target, thereby generating a response.
Learn more about Nerve impulse conduction here:https://brainly.com/question/38868670
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