Answer:
The threshold photon energy for DNA damage = 4.28 eV
Explanation:
According to the Planck - Einstein's equation, the energy of a photon, E is proportional to its frequency; E = hf where f is frequency and h is Planck's constant.
Also, frequency, f = velocity /wavelength
f = c/λ where c is the velocity of light
E = hc/λ
h = 6.63 × 10^-³⁴ Js;
c = 3.0 × 10⁸ m/s;
Threshold wavelength, λ = 290 nm = 2.9 × 10^-7 m
E = (6.63 × 10^-³⁴ × 3.0 × 10⁸) / 2.9 × 10^-⁷
E = 6.85 × 10^-¹⁹ J
1 ev = 1.602 × 10^-¹⁹ J
6.85 × 10^-¹⁹ J = 6.85 × 10^-¹⁹ J × 1 eV / 1.602 × 10^-¹⁹ J = 4.28 eV
Therefore, the threshold photon energy for DNA damage = 4.28 eV
As you are walking home from studying at the library late one evening, you get startled by a strange sound behind you. This activates your sympathetic nervous system. What affect does this change have on stroke volume? Group of answer choices Stroke volume will increase due to an increase in contractility. Stroke volume will decrease due to reduced blood pressure. Stroke volume will increase due to increased blood pressure. Stroke volume decreases due to an increase in contractility. Stroke volume will increase due to a decrease in contractility.
Answer:
Stroke volume will increase due to an increase in contractility.
Explanation:
When the individual is going through a stressful situation, the sympathetic nervous system, in conjunction with the hypothalamic-pituitary-adrenal (HPA) system, sends signals to prepares the body for stressful situations.
The body gets ready to respond to stress by increasing heart biting frequency and strength, contractibility, blood pressure, stimulating respiration and dilating respiratory tracts.
Stroke volume refers to the blood volume ejected from the ventricles as a result of the heart contraction. As said before, stressful situations increase heart bitting frequency and strength, as well as contractibility. Contractibility also influences stroke volume.
Stroke volume is determined by the difference in values of the end-diastolic volume and the end-systolic volume → SV = EDV - ESV
Contractility is one of the main factors that influence stroke volume, by affecting the end-systolic volume. It does not alter the diastolic volume. Consequently, there is an increase in stroke volume.
The central factor of systolic ejection is the myocardium sarcomere contractibility. The sarcomere´s contractile capability generates strength to become shorter after myosin heads join to the uncovered actin-binding points forming cross-bridges.
Which of the following identifies the only way to ensure a product is healthful?
Answer:
C. check the nutrition facts on the back
if it's wrong then it's D. buy the name brand instead of generic
Explanation:
A male rabbit w the genotype GGbb is crossed w a female rabbit with the genotype ggBb the square is set up below
Which of the following best describes why the two organisms you chose are closely related to each other using evidence from the chart?
Dehydration synthesis is involved in the synthesis of all the following except
1. DNA
? proteins.
priysaccharides.
4. lipids:
5. monosaccharides.
Answer:
Please dont delete
Explanation:
Hello. I am sorry that I can not answer your question but I am doing this so I can get answers of my own. I appreciate your understanding and I hope you get your answer soon. Good luck!
name four types of pathogens that could cause infectious diseases?
Answer:
viruses, bacteria, fungi, protozoa, and worms.
Explanation:
The diagram represents a taxonomic tree showing the possible evolution of six species of finches.
The most likely explanation for the branching pattern seen in the circled region labeled X is that:
A.
environmental changes resulted in extinction
B.
speciation occurred as a result of inbreeding
C.
no speciation occurred during this time
D.
environmental changes influenced speciation
Answer:
Option B
Explanation:
As we can see in the figure, three species of the finches in circle lie on the same main branch as three sub branches. This is an example of speciation caused by interbreeding of species which led to removal of deleterious genes and then caused emergence of three species adaptable to the existing environmental conditions.
Hence, option B is correct
girl j0in
fuy-nezb-ujd
Answer:
Hello
Explanation:
1. A food chain is one part of a food web. Which list is part of the food web shown above?
A diatoms-fish-leopard-seal-orca
B diatomskrill--fish-great white
shark-orca
C copepodsdiatomskrill--fish-
leopard-seal-orca
Dorca--leopard-seal--squid-copepods- diatoms
Help pls will get brainliest
NO LINKS Roundworms use the_____ route to move between two dogs.
Answer:
Feces is your answer. AKA poop.
Explanation:
When water evaporates,
the particles
A stop moving
B. move faster
C. move slower.
D. explode.
The directions in our genes allow us to make _____________________________ that carry out specific tasks. helpppp
Answer:
Features
Explanation:
Discribe the activities that lead to the birth of a child
what is the main point of the villi
Answer:
The villi of the small intestine project into the intestinal cavity, greatly increasing the surface area for food absorption and adding digestive secretions. The villi number about 10 to 40 per square millimetre (6,000 to 25,000 per square inch) of tissue.
The ligand binding domain of a protein must be inserted in
Which is NOT part of the excretory system
A.Bladder
B.Kidneys
C.Urethra
D.Large intestine
Answer:
Large intestine
Explanation:
This is the urinary system, therefore the intestines have nothing to do with it.
In order to perceive forms and patterns from incoming stimuli, individuals utilize____.
A. feature analysis
Group of answer choices.
A. feature analysis
B. change blindness
C. selective attention
D. inattentional blindness
Answer:
A. feature analysis
Explanation:
Stimulus can be defined as an obvious change in either the chemical or physical structure of an organism' environment (either external or internal). Thus, all living organisms (both animals and plants) respond to changes in their environment and consequently, an appropriate response or reaction is made. Also, stimulus arising from within the organism is known as internal stimulus while those from its environment are known as the external stimulus.
In organisms, the specialized cells that detect stimulus are generally known as sensory receptors while a group of these receptors is referred to as sense organ. Therefore, the senses are necessary for behavior because stimuli must be sensed in order to respond.
Stimulus control can be defined as a phenomenon that arises when a living organism responds or behaves in the presence of a stimulus and in another way in the absence of a stimulus.
For example, opening the door of a microwave oven as soon as its timer beeps.
Example II; When your body touches a hot object, you quickly move away and feel some pain subsequently.
In order to perceive forms and patterns from incoming stimuli, individuals utilize feature analysis of the signals from the environment.
Answer: A
Explanation: on edge 2021
Brainliest please
And thanks
Molly wanted to test out new NikeSpeed running shoes that claim to make her run faster than her regular Nike shoes. If she wanted to test these shoes, what would be her:
Independent variable:
Dependent Variable:
TWO controlled variables:
Control Group:
Experimental Group
Answer:
Independent variable: type of shoe
Dependent Variable: running speed
TWO controlled variables: same running distance, same runner
Control Group: running with the regular Nike shoes
Experimental Group: running with the new Nikespeed shoes.
Explanation:
According to this question, Molly wants to test her new NikeSpeed running shoes that claim to make her run faster than her regular Nike shoes.
- Independent variable is the variable of an experiment that is subjected to change or manipulation by the experimenter. In this experiment, the independent variable is the SHOES that Molly wants to test.
- Dependent variable is the measured variable that responds to the change made to the independent variable. In this case, the dependent variable is the RUNNING SPEED.
- Control variable is the variable that must be kept unchanged throughout the experiment in order not to change the experiment outcome. The control variables include; SAME RUNNING DISTANCE, SAME RUNNER (MOLLY) etc.
- Control group is the group of an experiment that does not receive the experimental treatment. In this case, it is RUNNING WITH THE REGULAR NIKE SHOES.
- Experimental group is the group that receives the experimental treatment. In this case, it is RUNNING WITH THE NEW NIKE-SPEED SHOES.
Lunar Eclipse. Choose ALL that apply
Lesson 3.07
Question 18 options:
Earth is directly between the moon and sun
Light from the sun is blocked
Earth casts its shadow on the moon
The moon turns dark
Answer:
All options are correct
Explanation:
In Lunar eclipse, Earth comes in between the sun and moon. Due to this, the sun light falls on the earth and its shadow is created that prevent the moon from shining.
In other way earth block the sun light reaching moon by coming in between the sun and moon.
Hence, All the options are correct
Please help I really need it pleaseeee
Answer:
Lizards and birds produce amniotic eggs.
Sharks were the first animals to have jaws.
Ray-finned fish and sharks are similar in that they both have paired appendages and jaws.
Birds are more closely related to crocodiles than they are mammals.
Explanation:
When a novel trait is labeled on a cladogram only the animals depicted after the label exhibit the trait.
Organisms that are located on the same clade (branch) are closely related.
Storz (2007) describes an adaptive response to low partial pressure of oxygen in an environment at high elevation. Describe three other environmental conditions besides high elevation that might result in adaptation to hypoxia. List an organism found in each of the described environmental conditions that would be predicted to exhibit adaptive responses to low partial pressure of oxygen.
Answer:
Enhanced ventilatory abilities, enhanced percentage removal of O2 from the ventilatory stream and large gill surface areas.
Explanation:
Enhanced ventilatory abilities, enhanced percentage removal of O2 from the ventilatory stream and large gill surface areas are the three other environmental conditions besides high elevation that might result in adaptation to hypoxia. These abilities will increase the resistance to lower oxygen levels in the surrounding environment. Fish is the organism which used these types of adaptation for their survival in the surrounding of low oxygen levels.
how contractile vacuole function in osmoregulation
Answer: A contractile vacuole (CV) is an organelle, or sub-cellular structure, that is involved in osmoregulation and waste removal. ... In freshwater environments, the concentration of solutes inside the cell is higher than outside the cell. Under these conditions, water flows from the environment into the cell by osmosis. The contractile vacuole (CV) complex is an osmoregulatory organelle of free-living amoebae and protozoa, which controls the intracellular water balance by accumulating and expelling excess water out of the cell, allowing cells to survive under hypotonic stress as in pond water.
Explanation:
what process do plants release water into the air
Answer:
transportationnnnnnnnnnnnnnnnnnn
Viroids’ largest impact is on ________.
Answer:
the agriculture indus
Correct answer: the agriculture indus
Scientists can create transgenic organisms by inserting foreign DNA randomly into the chromosomes of a host. A scientist might do this in order to express genes carried in the foreign DNA and in this case the foreign DNA is often engineered to include insulator sequences at the ends of the foreign sequence. Why insulators would be useful in this context
Answer:
Insulator sequences serve as a boundary between two genes. In this case, the insulator sequence is a boundary between the organism's normal DNA and the inserted foreign DNA. The insulator will protect the inserted DNA from any regulatory effects that may come from the neighboring gene.
to answer the following questions 1. How many tons of coal, oil, and gas are estimated to exist in the earth? a. 2200 b. 4 million c. 3300 billion d. 270 million
1.06 trillion tonnes of coal left- :>
A crop-dusting plane has to fly low and slow. It needs wings with a surface area ____________________the surface area of a jet wing.
a.
less than
c.
greater than
b.
equal to
Please select the best answer from the choices provided
A
B
C
Name the major nitrogenous waste product in nile perch
Answer:
Any metabolic waste product that contains nitrogen. Urea and uric acid are the most common nitrogenous waste products in terrestrial animals; freshwater fish excrete ammonia and marine fish excrete both urea and trimethylamine oxide.
Assume that gene A controls the conversion of a white pigment, P0 into another white pigment, P1 the dominant allele A specifies an enzyme necessary for this conversion, and the recessive allele a specifies a defective enzyme without biochemical function. Gene B controls the conversion of the white pigment, P1 into a pink pigment, P2 the dominant allele, B, produces the enzyme necessary for this conversion, and the recessive allele, b, produces a defective enzyme. The dominant allele, C, of the third gene specifies an enzyme that converts the pink pigment, P2 into a red pigment, P3 its recessive allele, c, produces an altered enzyme that cannot carry out this conversion. The dominant allele, D, of a fourth gene produces a polypeptide that completely inhibits the function of enzyme C; that is, it blocks the reaction P2-P3 Its recessive allele, d, produces a defective polypeptide that does not block this reaction. Assume that flower color is determined solely by these four genes and that they assort independently. In the F2 of a cross between plants of the genotype AA bb CC DD and plants of the genotype aa BB cc dd, what proportion of the plants will have (a) red flowers? (b) pink flowers? (c) white flowers?
Answer:
Red = 27/256Pink = 117/256White = 112/256Explanation:
Available data:
Four diallelic genes: A, B, C, DAA and Aa allows the conversion of P0 tp P1, while aa does notBB and Bb allows the conversion of P1 tp P2, while bb does notCC and Cc allows the conversion of P2 tp P3, while cc does notDD and Dd inhibit the action of allele C (P2 to P3), while dd does notThis is:
In the presence of the dominant alleles A, B, and C, the three might occur:
Po (white 0) ----> P1 (White 1) ----> P2 (Pink)----> P3 (Red)
A B C
In the presence of the recessive alleles a, b or c, the three reactions or some of them might not occur ( the X represents the inhibition of the reaction):
Po (white 0) --X--> P1 (White 1) --X--> P2 (Pink)--X--> P3 (Red)
a b c
In the presence of allele D, the last reaction is not possible, because D inhibits the action of C
P2 (Pink) --X-->P3 (Red)
C + D
So, in order to get Red flowers we must have the next genotype: A-B-C-dd (The three reactions can occur, and D must be absent)To get Pink flowers we must have the next genotypes: A-B-C-D- (D Inhibits C, hence it inhibits the third reaction) or A-B-ccD- or A-B-ccdd (cc does not allow the third reaction to happen, independently of the D gene presenceTo get White flowers we must have the next genotypes: aaB-C-D-,aabbC-D-, aaB-ccD-, aabbccD-, aabbccdd, aaB-C-dd, aaB-ccdd, aabbC-dd, A-bbC-D-, A-bbccD-, A-bbC-dd, A-bbccdd (aa must be present to get a white0 flower, or bb must be present to get a white1 flower)In the proposed problem, we have that the parental are AAbbCCDD and aaBBccdd, so we can tell that the whole F1 progeny will be heterozygous for the four genes, this is AaBbCcDd.
Knowing that these four genes assort independently, then we can infer that the F2 will have the next genotypic proportions for each gene:
AA + Aa=3/4aa= 1/4BB + bb= 3/4bb = 1/4CC + Cc = 3/4cc= 1/4DD + Dd =3/4dd= 1/4So, to get each of the mentioned genotypes for each trait, we must multiply their respective genotypic proportions, like this:
Red: A- x B- x C- x dd: 3/4 x 3/4 x 3/4 x 1/4 = 27/256Pink: A- x B- x C- x D-: 3/4 x 3/4 x 3/4 x 3/4 = 81/256A- x B- x cc x D-: 3/4 x 3/ x 1/4 x 3/4 = 27/256
A- x B- x cc x dd: 3/4 x 3/4 x 1/4 x 1/4= 9/256
By summing these proportions, we can get the proportion of all the pink flowers: 27/256 + 81/256 + 27/256 + 9/256= 117/256
White: To get the proportion of white flowers, you can repeat the same multiplications as before for each possible white genotype and then sum the results, as we did for pink flowers. Or you can extract from the total number of flowers (256), the amounts of red and pink flowers (27 and 117). This is: 256 - (27 + 117) = 112.Then 112/256 is the proportion of white flowers.
Which of the following countries currently contributes the most lumber to the international market?
China
Canada
Costa Rica
The United States
Answer:
Canada
Explanation: