Answer:
teratogens
Explanation:
The factors or any of the agent that can cause malformations in the development of the embryo are termed as teratogens. Behavioural teratogens are the ones that can cause harm to the development of the brain at the prenatal stage due to which the intellectual ability and the emotional functioning of the child can be affected in the future. The time the effect shows up in the future depends on the stage of the embryo/foetus development at which the child got exposed to the teratogen. In the given situation Austin is suffering from ADHD and hyperactivity that reflects a faulty brain development due to the exposure of teratogens that his mother consumed while he was conceived.Final answer:
Austin's hyperactivity may be due to prenatal exposure to teratogens like nicotine, which can lead to developmental issues such as ADHD, with factors like maternal stress also playing a role.
Explanation:
Six-year-old Austin is hyperactive and might be showing the effects of behavioral teratogens that his mother ingested while he was in the womb. Teratogens are agents, like chemicals or viruses, that can cause harm to the developing fetus, leading to birth defects or developmental issues such as ADHD. Research has demonstrated that certain substances consumed during pregnancy can have significant impacts on child behavior and development. Notably, exposure to nicotine from cigarette smoke and maternal stress are associated with an increased risk of ADHD symptoms in children. Additionally, environmental toxins and factors such as lead exposure and high levels of prenatal stress from adverse life events are linked to ADHD. However, several misconceptions about ADHD's causes, including sugar intake, food allergies, and poor parenting, have been debunked through research.
When you eat a hamburger, some of the energy in the food is converted to ATP that your cells can use to do all kinds of work, some of the energy is stored for later use, and some of the energy is dissipated as heat. The amount of energy before and after eating the hamburger is the same. This illustrates the:
Complete question:
When you eat a hamburger, some of the energy in the food is converted to ATP that your cells can use to do all kinds of work, some of the energy is stored for later use, and some of the energy is dissipated as heat. The amount of energy before and after eating the hamburger is the same. This illustrates the:
a. the cell theory.
b. the theory of evolution.
c. the central dogma.
d. the second law of thermodynamics.
e. the first law of thermodynamics.
Answer:
e. the first law of thermodynamics.
Explanation:
The first law of thermodynamics is about the fact that the creation and destruction of energy are not possible. During any biological or other processes, one form of energy can be converted into another form. But the total amount of energy before and after the process remains the same. In the given example, the part of the energy of a hamburger is used to perform functions, the part is stored in tissues and rest is lost as heat. However, the total energy content remains the same. This represents the first law of thermodynamics.
In an analysis of the nucleotide composition of a double stranded DNA to see which
bases are equivalent in concentration, which of the following would be true?
a. A = G and C = T and A + C = G + T are both true.
b. A = G and C = T
c. A + T = G + C
d. A + C = G + T
e. A = C
Answer:
C) A + T = G + C
Explanation:Erwin Chargaff suggested the rule of the base pairing of DNA structure which is that purine binds pyrimidine or adenine binds thymine and guanine binds cytosine. The composition of adenine and thymine and guanine and cytosine equals 100 percent.
In the given question, since option C shows that A binds T and G binds C and their composition equals 100%, therefore, Option-C is the correct answer.
Thus, Option-C is the correct answer.
Using the Hardy-Weinberg Law of Equilibrium, evaluate whether the populations are in equilibrium or not.
Scenario 1 You have a population of 1000 people, and you are looking at the population genetics of a blood marker that has two alleles. The dominant allele (Y) makes the protein, and the recessive allele (y) does not make the protein. When you test the blood of the population, you find: 490 people have the genotype YY 420 people have the genotype Yy 90 people have the genotype yy What are the allele frequencies (Y and y)? What are the expected genotype frequencies (YY, Yy, and yy)? Is the population in equilibrium? Yes or no? If the population is not in equilibrium, which of the assumptions of Hardy-Weinberg do you think may have been violated?
Scenario 2 Now, a few of the people in your study population move to settle an isolated, empty island. You travel to the island and do a genetic survey of the population. 60 are YY 40 are Yy 0 are yy What are the allele frequencies (Y and y)? What are the expected genotype frequencies (YY, Yy, and yy)? Is the population in equilibrium? Yes or no? If the population is not in equilibrium, which of the assumptions of Hardy-Weinberg do you think may have been violated?
Answer/Explanation:
Scenario 1
What are the allele frequencies (Y and y)?
490 people have the genotype YY, 420 people have the genotype Yy, and 90 people have the genotype yy.
The allele frequency of Y is 490 (from the YY group) + half of 420 (from the Yy group) = 700. There are 1000 people total, so the allele frequency of Y is 700/1000 = 0.7 (70%)
The allele frequency of y is 90 (from the yy group) + half of 420 (from the Yy group) = 300. There are 1000 people total, so the allele frequency of y 300/1000 = 0.3 (30%)
This checks out, as the equation for the allele frequencies for 2 alleles of a gene is p + q = 1.0. In this case, Y + y = 1 (as 0.7 + 0.3 = 1)
What are the expected genotype frequencies (YY, Yy, and yy)?
The expected genotypes based on genotype frequencies p and q are calculated from the following equation:
p² + 2pq + q² = 1 (or 100%).
Therefore, the expected frequency of YY (p²) is 0.7² = 0.49 (or 49%). For a population of 1000, that means we expect 490 YY.
The expected frequency of Yy (2pq) is 2 x 0.3 x 0.7 = 0.42 (or 42%) For a population of 1000, that means we expect 420 Yy.
The expected frequency of yy (q²) is 0.3² = 0.09 (or 42%) For a population of 1000, that means we expect 90 yy.
Is the population in equilibrium? Yes or no?
This matches up with our observations exactly (and the total of the values 0.49 + 0.42 + 0.09 = 1), meaning that yes, the population is in Hardy Weinberg equilibrium.
Scenario 2
What are the allele frequencies (Y and y)?
60 people have the genotype YY, 40 people have the genotype Yy, and 0 people have the genotype yy.
The allele frequency of Y is 60 (from the YY group) + half of 40 (from the Yy group) = 80. There are 100 people total (60 + 40 + 0), so the allele frequency of Y is 80/100 = 0.8 (80%)
The allele frequency of y is 0 (from the yy group) + half of 40 (from the Yy group) = 20. There are 100 people total (60 + 40 + 0), so the allele frequency of Y is 20/100 = 0.2 (20%)
What are the expected genotype frequencies (YY, Yy, and yy)?
The expected genotypes based on genotype frequencies p and q are calculated from the following equation:
p² + 2pq + q² = 1 (or 100%).
Therefore, the expected frequency of YY (p²) is 0.8² = 0.64 (or 64%). For a population of 100, that means we expect 64 YY.
The expected frequency of Yy (2pq) is 2 x 0.8 x 0.2 = 0.32 (or 32%) For a population of 100, that means we expect 32 Yy.
The expected frequency of yy (q²) is 0.2² = 0.04 (or 4%) For a population of 100, that means we expect 4 yy.
Is the population in equilibrium? Yes or no?
No, the population deviates from Hardy Weinberg equilibrium, because we are missing any individuals with a yy genotype. This means the observed frequencies are not true of the expected frequency
If the population is not in equilibrium, which of the assumptions of Hardy-Weinberg do you think may have been violated?
The assumption that has likely been violated is that the population is large. This population is small, and is a small sample of the original population, meaning genetic variation is reduced.
The only phylum in the group Parazoans is ________. A. Porifera B. Cnidaria C. Lophotrochozoa D. Ctenophora E. Ecdysozoa
Answer:
A. Porifera
Explanation:
Parazoan is a sub-kingdom of animal consisting only of the phylum of sponges (porifera), having two tissue layers only and lacking a nervous system and true digestive cavity.
They have certain characteristics like: sponges are marine, but there are some freshwater sponges that enjoy their water without salt. Most sponges do not have any type of symmetry, but some are radially symmetrical and they come in a variety of shapes, colors, and sizes, they are multicellular, heterotrophic and lack cell walls. Unlike other organisms, sponges lack true tissues and organs.
The mesohyl functions as an endoskeleton in most sponges, and is the only skeleton in soft sponges. This mesohyl is stiffened by mineral spicules, by spongin fibers or both.
Following carbon atoms around the Calvin cycle. The net reaction of the Calvin cycle is the conversion of CO2 into the three-carbon sugar G3P. Along the way, reactions rearrange carbon atoms among intermediate compounds and use the ATP and NADPH produced by the light reactions. In this exercise, you will track carbon atoms through the Calvin cycle as required for the net production of one molecule of G3P. For each intermediate compound in the Calvin cycle, identify the number of molecules of that intermediate and the total number of carbon atoms contained in those molecules. As an example, the output G3P is labeled for you: 1 molecule with a total of 3 carbon atoms. Labels may be used once, more than once, or not at all.
a. 3 molecules 3 carbon.
b. 6 molecules 18 carbon.
c. 6 molecules 18 carbon.
d. 5 molecules 15 carbon.
e. 3 molecules 15 carbon.
f. 3 molecules 15 carbon.
Answer:
Explanation:
The Calvin cycle represent the second phase of photosynthesis ( the dark phase of the reaction not because it is dark but because it not dependent on light). The ATP and NADPH produced in the light dependent phase used to synthesize glucose. The intermediates and there carbon content are stated below:
3 molecules of carbon dioxide total carbon = 3 carbon
6 molecules of 3-phosphoglycerate total carbon = 18 carbon
6 molecules of 1,3-Bisphosphoglycerate total carbon = 18 carbon
5 molecules of glyceraldehyde -3-phosphate total carbon = 15 carbon
3 molecules of Ribulose-5-phosphate total carbon = 15 carbon
3 molecules of Ribulose-1,5-bisphosphate total carbon = 15 carbon
This is one of the processes by which ATP is synthesized. In eukaryotes, it takes place in the mitochondria during cellular respiration and in the chloroplasts during photosynthesis. In prokaryotes, it occurs in the cell membrane.
Answer:
answer you looking for is i think Phosphorylation.
Explanation:
please ask the question more meaningfully
Answer:
chemiosmosis
Explanation:
I did the USA Test Prep
The three-dimensional structure of macromolecules is formed and maintained primarily through noncovalent interactions. Which one of the following is not considered a noncovalent interaction?A) carbon-carbon bondsB) hydrogen bondsC) hydrophobic interactionsD) ionic interactionsE) van der Waals interactions
Answer:
carbon-carbon bonds.
Explanation:
The non-covalent bonds are not formed by the sharing of electrons between the bonded atoms. These bonds may be formed by some electrostatic attraction between the oppositely charged atoms or any other type of interaction. However, the carbon-carbon bonds are formed when there is a sharing of electrons between the two atoms of carbon. Each carbon atom has four electrons available for bonding. Two carbon atoms share their electrons to complete the stable configuration of the presence of eight electrons in the outer most shell. Therefore, carbon bonds are covalent bonds.
Members of two different species possess a similar-looking structure that they use in a similar way to perform about the same function. Which of the following would suggest that the relationship more likely represents homology instead of convergent evolution?
Answer: The member of two different species possess similar looking structure that in a similar way perform same function is homology.
Explanation: The term homology describes shared ancestry pair of structures. For example, apes and dogs are different and the arms of ape and forelegs of a dog are derived from ancestry tetrapod structure that perform similar function like aiding locomotion.
Most mammals have diploid body cells and haploid gametes. During __________, chromosomes from haploid gametes combine, and a __________ zygote is formed.
Answer:
During fertilization, chromosomes from haploid gametes combine, and a diploid zygote is formed.
Explanation:
Fertilization is the union of the male gamete(haploid chromosomes) with the female gamete(haploid chromosome) to form a diploid cell called zygote (with diploid chromosomes).
A food that results in a(n) _____ of nitrogen released from the body has a high biological value, meaning that the majority of the protein has been absorbed by the body
Foods with high biological value result in a decrease of nitrogen released from the body, indicating effective absorption of protein. Such foods are typically rich in essential amino acids.
Explanation:A food that results in a decrease of nitrogen released from the body has a high biological value. This means the majority of the protein in that food has been effectively absorbed by the body. Foods with high biological value are generally rich in essential amino acids that are not produced by the body, so they have to be acquired through diet. Examples of these foods include eggs, meat, and dairy products.
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A food with high biological value leads to minimal nitrogen waste as the protein is efficiently absorbed by the body.
Explanation:A food that results in a decrease of nitrogen released from the body has a high biological value, meaning that the majority of the protein has been absorbed by the body. When proteins are broken down during metabolism, nitrogenous waste is produced. Nitrogenous wastes are excreted from the body as they are toxic. The urea cycle is the primary mechanism by which mammals convert ammonia to urea for excretion. Overall, proteins with high biological value are those that are efficiently absorbed and utilized by the body, resulting in minimal nitrogen waste.
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These structures are very large, blunt, irregularly shaped processes. The only examples in the human body are on the femur. What bone marking is being described?
Answer:
Trochanter
Explanation:
The trochanter is a lateral projection of the femur (the longest bone in the human body) in the upper part of the thigh, that is, an irregular and large prominence of the femur. The greater trochanter is a prominent and relatively easy to palpate structure belonging to the femur, and serves as an insertion to many muscles that participate in the movement and stability of the hip. The lesser trochanter is less prominent and impossible to palpate due to its internal situation, it serves as an insert for some muscles such as the iliac psoas, one of those in charge of hip flexion.
When his husband turns out the light at night, Rodney cannot see anything at all in his bedroom. After a while his eyes adjust and he can see some shapes in the darkness of the room, but he cannot see any colors. Which sensory receptors are responsible for processing his ability to see objects in the darkness?
Answer:
rod photoreceptors
Explanation:
The retina of the eye has 2 types of sensory receptors or photoreceptors. They are the rod cells and the cone cells. The rod cells mostly found at the outer edge of the retina of the eye, which are numerous and more sensitive compared to the cone cells. The cone photoreceptors are found in the macula.
The rod photoreceptors are responsible for night vision mainly and function in dim light or less intense light, while the cone receptors are responsible for color sensitivity.
The rod photoreceptors are responsible for processing his ability to see objects in the darkness.
Community constituencies of a local health department (lhd) include
the land mass in the geographic
region served by the LHD.
What is the function of a selectively permeable membrane? A. It allows no large molecules to leave the cell and all large molecules to enter. B. It allows some molecules to enter the cell and blocks entry to others. C. It allows all molecules to enter the cell but blocks them all from leaving. D. It allows all molecules to enter the cell and allows all molecules to leave.
Answer: Option b: it allows some molecules to enter the cell and block entry to others.
Explanation: selective permeability allows those molecules to enter the cell which are small, uncharged. Large molecules pass slowly.
Describe the role of each of the following mechanisms in determining an individual’s eating habits and body weight.• Biological Mechanisms Learning Mechanisms• Body or brain chemistry Reinforcement• Brain structure Modeling• Genetics Cultural Factors
Answer:
Explanation:
1. Biological Mechanism: This are things like hunger, appetite and taste of the individual. Every individual is unique and one's hunger and appetite determines how often and how much they eat respectively. The higher these are, the more likely they are to consume calories. The taste is even more relevant as it speaks to what kind of food the individual likes, is it high calorie or low? Is it fat rich or low fibre? Etc.
Learning Mechanism: This are relevant mostly to students. Studying patterns greatly affect eating habits and body weight. Time of sleep, stress patterns, balanced diet and even regularly missing a meal for a study group directly affects metabolism patterns. For instance, eating breakfast regularly boosts metabolism, and is good for weight balance.
Reinforcement: Certain foods are quite addictive and so reinforce their consumption by adjusting brain chemistry.
Body or Brain Chemistry: Studies done on Obesity have found that some individuals are susceptible to environmental food cues than others due to differences in brain chemistry that make eating more habitual and less rewarding. This means that not only do they eat habitually but that it is less satisfying. This is a major contributor to obesity. These Peculiarities in brain/body chemistry affect people's eating pattern and their weight.
Brain Structure Modeling: Uncontrolled eating is also positively associated with gray matter volume (GMV) of the cerebellum, and negatively associated with the Gray matter volume on the left side of the anterior cingulate cortex, middle cingulate cortex, and supplementary motor areas. What this means is that individuals with more gray matter volume in these areas of their brains are more presdusposedto excessive eating habits and this might lead to weight problems and it's related health risks.
Genetic Factors: These factors are genetic predisposition to eating disorders, genetic influence on taste, meal selection and appetite processing.
These also influence how much the individual ends up eating and what type of food they eat.
Cultural Factors: This include type of food found in one's culture, polite eating habits there, the ingredients used for cooking said culture. It also encorporatea the individual's class as food poverty is known to exist affecting about 14 million people. There's also available and affordability of healthy food options. This affects both eating habits and weight as less healthy junk food are more likely to be calorie dense.
PS: The eating pattern and body weight factors are closely correlated as the eating pattern explains what the weight situation might mirror.
Healthy eating and a balanced diet regulate body weight and health. The eating behaviour targets the weight loss and gain of an individual.
The biological and learning mechanism determines the eating habits as:
Biological Mechanisms:
1. Brain and body chemistry: The release of hormones and chemicals from the body regulates eating habits and weight. Examples are dopamine, glucose, glucagon etc.
2. Brain structure: The gray matter volume of brain structures affects the weight and habits as the lateral and ventromedial hypothalamus regulates the eating and satiety centers respectively.
3. Genetics: the types of food a person consumes and his taste depends on genetic predispositions and influences the meal and taste preferences.
Learning Mechanisms:
1. Reinforcement: The brain adjusts itself sometimes according to the addicting taste of some food items and these aversions modify the eating behaviours.
2. Modeling: Role and observational modelling adjust the eating habits of a person visualizing, hearing or reading about the favourite food items.
3. Cultural factors: The body perception like the chubby or thin and slim body standards of a particular culture affects the eating and diet habits of individuals and affects the weight.
Therefore, eating habits and patterns are influenced by biological and learning mechanisms.
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An example of a positive feedback loop ________.
a. are birds migrating south in response to colder temperatures
b. is a thermostat turning on the furnace as the temperature drops
c. is melting arctic snow exposing dark surfaces that heat up and cause further melting
d. are predators eating most of their prey and then declining in numbers
e. is a pond becoming more acidic as a result of pollution.
Answer:
The answer is option c. is melting arctic snow exposing dark surfaces that heat up and cause further melting
Explanation:
Positive feedback loop is the process that occurs when the product of a reaction exacerbates the reaction. Melting artic snow expose dark surfaces that heat up and result in further increase in melting.
Final answer:
A positive feedback loop example c. is melting arctic snow exposing dark surfaces that heat up and cause further melting.
Explanation:
An example of a positive feedback loop is melting Arctic snow exposing dark surfaces that heat up and cause further melting. In ecological and biological systems, a positive feedback loop refers to a process that enhances or amplifies changes, leading to an increasing deviation away from the system's original state. For instance, melting permaf_rost in the Arctic leads to the release of greenhouse gases like carbon dioxide and methane, which in turn cause further warming and more melting. This self-amplifying cycle is a classic example of positive feedback in the Earth's climate system.
In what way does the interior surface of a cell membrane of a resting (nonconducting) neuron differ from the external environment? The interior is ________.
Select one:
a. positively charged and contains more sodium
b. positively charged and contains less sodium
c. negatively charged and contains less sodium
d. negatively charged and contains more sodium
Answer: option C) negatively charged and contains less sodium
Explanation:
In the absence of any stimulus, a neuron is said to be resting. During this time, more positively charged potassium ions (K+) than sodium ions (Na+) occupy the interior of its cell membrane, whereas more sodium ions than potassium occupies the exterior - making the cell membrane to be electrically Polarized with net positive charge outside and a net negative charge inside the cell membrane.
Thus, the interior is negatively charged and contains less sodium ions
The interior surface of a resting (nonconducting) neuron's cell membrane is negatively charged and contains less sodium, an ion distribution effect of sodium-potassium pump.
Explanation:The interior surface of a cell membrane of a resting, nonconducting neuron differs from the external environment in that it is negatively charged and contains less sodium. This is because of the distribution of various ions across the neural membrane at rest, largely due to the action of the sodium-potassium pump and various ion channels. Sodium ions are more concentrated outside the neuron, while potassium ions are more concentrated inside. This uneven distribution creates the negative charge within the neuron.
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The tendency to apply one's own cultural values in judging the behavior and beliefs of people raised in other cultures is known as
A. cultural relativism.
B. cultural universalism.
C. ethnocentrism.
D. egocentrism.
E. cultural anthropology.
Answer: The correct answer is ethnocentrism
Explanation:
An estimation of the worth of other people way of life based on ONLY your own perspective or better still cultural understanding of what to wear, how to greet, how or what to eat etc, that you are familiar with is referred to as ETHNOCENTRISM.
A massive cleaver is more effective for chopping vegetables than an equally sharp knife because of which of newton's laws?
Answer:
Newton's 1st Law
Explanation:
A knife is surely sharp but the cleaver requires less force as compared to the knife because of it's advanced design strategy. A knife can only chop one at a time but a cleaver is of more mass that means less force on a unit area is required to chop down the vegetables. If a arrangement of knives is so that they can perform simultaneously than they will require less time to get the jo done.
Final answer:
A massive cleaver is more effective due to Newton's second law of motion, as the greater force from the heavier cleaver results in more effective chopping.
Explanation:
A massive cleaver is more effective for chopping vegetables than an equally sharp knife because of Newton's second law of motion. According to this law, the change of motion of a body is proportional to and in the direction of the force acting on it. This means that when you use a heavier cleaver, the force exerted on the vegetables upon impact is greater, making it more effective in chopping through them, assuming both the cleaver and knife are equally sharp.
Cancer is a multistep process usually occurring over many years. The first step in the initiation process is thought to be caused by_________.
Answer:
Answer is genetic mutation in the growth regulatory genes.
Explanation:
Cancer is a disease cause by accumulated damage occurring to genes or continuous division of abnormal cells in the body. This may occur due to exposure to substances that are cancerous.
It can be be treated by a method known as chemotherapy.
There are some food items that can lower the risk of cancer in the body. These include berries, nuts, carrots , broccoli among others.
Note that cancer can spread to other parts of the body through lymph system and blood.
A plant cell is placed in distilled water, as shown in the figure. There is a net uptake of water by osmosis, causing the cell to become turgid. Select the correct statement about this setup, after the cell is fully turgid:_________A) The pressure potentials (ΨP) of the cell and its surroundings are the same.B) The water potentials (Ψ) of the cell and its surroundings are the same.C) Because the cell contains more solutes than the distilled water that surrounds it, the solute potential (ΨS) of the cell is higher than the solute potential of distilled water.
Answer:
The water potentials (Ψ) of the cell and its surroundings are the same.
Explanation:
When a cell is kept in hypotonic surroundings such as distilled water, the osmotic movement of water occurs towards the cell. The entry of water makes the cell swell up and it becomes turgid. Water potential is determined by solute and pressure potentials mainly. Here, the solute potential of the cell and the distilled water was different resulting in differences in their respective water potential values which in turn served as a driving force for endosmosis.
When the cell is fully turgid, the solute concentration of the cell and the surrounding distilled water become equal to each other. Under these conditions, the water potential of the cell and distilled water are the same.
Plants release water vapor through their leaves; this process is called ________.
a. magnification
b. percolation
c. condensation
d. transpiration
e. evaporation
Plants release their water vapor that help them to make a balance in their inside as well as outside. Plants release water vapor through their leaves; this process is called transpiration.
What is the role of stomata in leaves ?The role of stomata in the leaves is the exchange of gases through it, at night the stomata gets closed and in day they are open.
Water loss through the leaves takes place through stomata when the leaves stomata are open at that time, the various water loss through the stomata when the stomata are open for the exchange of gases where oxygen is taken out in exchange of carbon dioxide that is taken out.
Transpiration is an essential process in the mechanism of plants where the role of transpiration is to provide the leaf balance also transpiration helps to maintain the temperature cooling within the atmosphere.
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A scientific study looked at the effect of tanning beds on DNA damage. The scientists took skin cells and exposed them to UV radiation (the type used in indoor tanning beds) for different lengths of time: some for 1 minute, some for 5 minutes, some for 15 minutes, and some for 30 minutes. They then looked for signs of DNA damage and compared the results to cells that had never been exposed to UV light. What is the independent variable in this experiment
Answer:
Tanning of DNA using UV light at different time (1 minutes, 15 minutes, and 30 minutes)
Explanation:
Independent variable is the variable that was controlled or change and in this case it is the tanning of DNA with UV light at different times and the dependent variable is what is measured or the effect of the change in the independent variable which is DNA damage and the control was the cells that did not receive the treatment.
The independent variable in this experiment is the amount of time the skin cells were exposed to UV radiation. While UV-A radiation from tanning beds is considered 'safe' compared to UV-B, prolonged exposure can still cause DNA damage and increase the risk of cancer.
Explanation:The independent variable in the experiment is the length of time that the skin cells were exposed to UV radiation from tanning beds. This is what the scientists deliberately changed to observe what effect different durations of UV exposure would have on DNA damage in skin cells. They compared cells exposed for 1, 5, 15, and 30 minutes to cells not exposed to UV radiation at all.
It is important to note that the 'safe' UV radiation used in tanning salons is UV-A light, which has a longer wavelength than the more damaging UV-B radiation found in natural sunlight. Although it's branded as 'safe,' UV-A has enough photon energy to trigger the tanning mechanism in the skin, which is a defense mechanism. However, with prolonged exposure, UV-A radiation can still lead to cell damage and has the potential to induce cancer, as established by the World Health Organization's classification of UV radiation as a Group 1 carcinogen.
Darwin stated four conditions that are necessary for natural selection to occur. Which of these conditions is not fulfilled by Mycobacterium tuberculosis, the organism that causes tuberculosis?
Answer:
Mycobacterium tuberculosis fulfilled all the four conditions stated by Darwin.
Explanation:
Natural selection is the ability of an organism with favored heritable traits for survival and reproduction, have more offsprings or young ones than its peers , after transferring those heritable traits to the young ones.
The four conditions , necessary for natural selection as stipulated by Darwin are,
* reproduction
* heredity
* variation in organisms
* variation of an individual organism or character among others in the population.
Final answer:
All of Darwin's conditions for natural selection are met by Mycobacterium tuberculosis, particularly under the selective pressure of antibiotics where resistant strains survive and become predominant.
Explanation:
Charles Darwin identified essential conditions for natural selection to occur, which include variation of traits among individuals in a population, heritability of those traits, differential survival, and differential reproduction. Mycobacterium tuberculosis, the causative agent of tuberculosis, indeed fulfills these conditions, particularly in the presence of antibiotics.
Due to its slow growth rate and genetic variation, some individuals naturally possess mutations that confer resistance to antibiotics. When treated with antibiotics, susceptible bacteria are killed while resistant ones survive, reproduce, and pass on their resistant traits, leading to a population shift towards drug resistance.
Regarding the student's question on which condition is not fulfilled by Mycobacterium tuberculosis, all of Darwin's conditions for natural selection are generally met by this organism, especially in light of antibiotic resistance. The true question may be centered on whether this process is an example of artificial selection due to human intervention (using antibiotics) or natural selection. The change in environment, caused by the use of antibiotics, inadvertently selects for resistant strains of M. tuberculosis, making this an example of natural selection as the bacteria is adapting to a new environmental condition.
Earth is composed of a series of compositional layers such as the crust, Answer mantle , and core. The outermost part of Earth can be further subdivided on the basis of physical properties into a strong outer layer, the Answer composed of Answer and uppermost mantle, and a weaker underlying layer, the_______________.
The complete question is as follows.
Earth is composed of a series of compositional layers such as the crust, ______, and core. The outermost part of Earth can be further subdivided on the basis of physical properties into a strong outer layer, the ______ composed of _____ and uppermost mantle, and a weaker underlying layer, the _____, present in the upper part of the ____.
Answer:
Mantle, lithosphere, crust, asthenosphere, mantle.
Explanation:
The earth is the only planet that supports life. The earth has optimum temperature, atmosphere, hydrosphere and biosphere that makes life possible on the earth.
The earth is divided into three layers known as crust, mantle and core. The mantle is the middle layer of the earth. The lithosphere is the further sub division of the crust layer. The lithosphere includes the land area of the earth and further shows the crust layer. The upperside layer of mantle layer is asthenosphere.
Thus, the answer is mantle, lithosphere, crust, asthenosphere, mantle.
The mosses and ferns both require water to enable the sperm to travel to the egg and fertilize it. Does this indicate that the ferns and mosses have a close relation to water plants? Explain your reasoning.
Answer:
Yes
Explanation:
Current evolutionary hypothesis state that all plants share a common ancestor. However, throughout time, as plants needed to colonize other habitats to survive, they were forced to develop specific adaptations, for example, the development of seeds, which enables them to be spread (by wildlife) and colonize many habitats.
However, seedless plants, still require humid conditions. This is the case of ferns and mosses. These groups of plants didn't (or haven't) develop complete independence from water, therefore they still need to be close to moist areas.
Therefore, ferns and mosses indeed have a close relation to water plants. I would suggest an even closer one than those plants that have developed seeds and better adaptations to live their whole lives in land.
At the end of the electron transport chain, the electrons originally stripped from glucose combine with molecular oxygen to yield which compound?
Answer:
Water
Explanation:
Oxygen is the final electron acceptor in aerobic respiration. Moleculer oxygen is highly oxidizing agent and therefore a good elctron acceptor. At the end of electron transport chain oxygen accept electrons and combine with protons to form water. If a person is not breathing enough there will be not enough oxygen in the cells to accept electrons, ETC will stop and there will be no ATP production. A cell can't carry out its functions without ATP. Therfore cellular respiration is breathing, and breathing is life.
At the end of the electron transport chain, the electrons stripped from glucose combine with molecular oxygen to yield water.
Explanation:At the end of the electron transport chain (ETC) in cellular respiration, the electrons stripped from glucose during glycolysis and the citric acid cycle are transferred through a series of protein complexes and carriers in the inner mitochondrial membrane. These electrons ultimately combine with molecular oxygen (O2) to form water (H2O) through a series of redox reactions.
This process is known as oxidative phosphorylation and is a critical step in generating ATP (adenosine triphosphate), which is the primary energy currency of the cell. The energy released during this electron transfer is used to pump protons across the mitochondrial membrane, creating an electrochemical gradient that drives the production of ATP.
Learn more about electron transport chain here:https://brainly.com/question/24368622
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A tricky question with no single right answer: In maintaining the functional shape of an enzyme, are the non-covalent interactions or covalent bonds stronger?
Answer:
Covalent interactions are stronger, due to the fact that each individual bond is a much stronger bond.
WILL BRAINLIEST
A student is examining leaf cells. Which organelle is most likely to be missing from the cells?
a cell wall
chloroplasts
centrioles
a cell membrane
Answer:
The correct option is C) centrioles
Explanation:
A centriole can be described as an organelle which is usually present inside a centrososme. It is absent in the plant cells but present in the animal cells. Hnece, the correct option is C) centrioles.
Opther options are not correct because a cell wall, chloroplasts, a cell membrane can all be seen in a leaf cell.
Imagine that you have found the remnants of a robin's egg on the ground. From your biology course, you know that this eggshell is composed of calcium. What else can be said of this eggshell?
Answer:
The birds are oviparous in nature and produces eggs that are hatched later by the parent. the egg hatching require proper heat and protection from the external enemy.
The egg shell is the hard covering of the egg of the bird that is made of the calcium. The egg shell protect the egg from the external environment. The calcium layer for the egg shell formation is obtained by the oseteoclast property of the cells.