In an experiment to determine the acceleration due to gravity, one student holds a pencil at arm’s length and drops it. Another student starts a timer when the first student lets go and stops the timer when the pencil hits the ground. They repeat this several times and take an average. Is this a valid experiment, why or why not?

Answer:

The correct answer is - No, it is not valid because the short distance means there will be a lot of error due to the student's reaction time.

Explanation:

In this experiment to determine the acceleration due to gravity, there may be errors because of the student’s reaction time. The reaction can be late or early than prior reactions.

The other error can be caused by the distance was only at arm’s length throughout the experiment, which means that there was no independent variable that is the difference or change in the distance. This also makes the experiment invalid.

A stem cell is
A. A specialized cell that can divide limitlessly but cant differentiate
B. A specialized cell that can divide limitlessly.
C. An unspecialized cell that cant divide limitlessly nor differentiate into specialized cell.

The toxins responsible for botulism are proteins that inhibit the release of acetylcholine, which in turn can cause muscle paralysis. In extreme cases the paralysis can involve the respiratory muscles, and people can die of respiratory failure. This mechanisms of action indicates that the toxins are

Transfusion of type AB blood would introduce both A and B ______________ which would be ______________ monosaccharides type

You learned in the previous lesson that T cells require two independent signals to become activated. When T cells are activated, they acquire effector functions and begin to proliferate. This two-signal mechanism prevents the expansion of self-reactive effector T cells. Similarly, B cell receptor signaling alone is not sufficient to activate B cells. B cells require assistance from helper T cells to become activated by monovalent protein antigens and gain certain immune functions. What changes do you suspect will occur to B cells when they are activated by protein antigen and receive T cell help? (select all that apply)
a) They will generate memory cells that can respond to a subsequent exposure to antigen.
b) Their immunoglobulin genes will be mutated in a way that alters antigen affinity.
c) The isotype of their immunoglobulin (Ig) genes will change.
d) They will proliferate and expand.
e) They will secrete antibodies.

biology chapter 33 assessment 972

Linda received the flu vaccine this year.

Which of the following statements is true?


Linda's T-cells will produce memory cells against the virus.


Linda's body will produce antigens against the flu virus.


Linda's immune system will produce lifelong immunity against any form of the flu.


Linda's immune system will produce antibodies against the flu virus.

in some plants pink flowers are dominant over yellow flowers if Mario crosses two hybrids what happens

g The greater tubercle of the humerus is analog to the _______________. Group of answer choices lesser tubercle of the humerus lesser trochanter of the humerus greater trochanter of the femur lesser trochanter of the femur

Hello.
All of the DNA in the nucleus of a cell can potentially be mutated?

True or false?

I will give brainly

all dicots are annuals true or false​

For those women who are not progressing at all or the baby is showing early signs of distress, the decision is
often made to induce labor. This uses a synthetic form of oxytocin, called Pitocin, which is given intravenously
(IV) to the woman to get the contractions going. It is often stopped after a few hours. Why might that be?

Match the following description with the appropriate type of respiration:

a. occurs in the mitochondria
b. resting muscles depend on this type of respiration
c. lactic acid builds up in muscle fibers
d. rapidly produces ATP for short time periods
e. produces large quantities of ATP but takes longer to synthesize

1. anaerobic respiration
2. aerobic respiration

What determines the temperature of a layer of the atmosphere?
A. The way thlmayer interacts with the layer below it
B. The average wind speed in the layer
c. The way the layer interacts with solar radiation
D. The altitude of the solar radiation

why is meiosis called reduction division?​

What is a community?
1 all the animals that live in a habitat
2 a single species that lives in a habitat
3 all the species that live in a habitat
4 a population that lives in a single habitat

What is photosynthesis???? ​

From a chemical view, how is an amino acid is being recognized by its specific aminoacyl tRNA synthetase?

Using the field of view calculated in Exercise 1 for the high power lens, what is the approximate diameter of each of the cells in the Bacteria Coccus Form slide in Photo 10? Show your calculations.
400x Magnification
0.4 mm field view

6. Compare the different measurements of the thermometer which are used.​

A population of lab rats recently escaped into the sewer system of Washington, D.C. A brave researcher sampled this population and estimated the following phenotypic frequencies (which were caused by a single gene with two alleles: E and e).
61% normal eyes (EE)
26% cross-eyed (Ee)
13% blind (ee)
If this population were to reach a Hardy-Weinberg Equilibrium (HWE) in one generation, what would the phenotypic frequencies be in that new HWE generation? Let freq (e)=p and freq (e)=q. (Tip first calculate p and q from the observed, and provided, phenotypic frequencies)
freq EE =
freq Ee =
freq ee =

How does energy acquisition in the deep sea differ from energy acquisition near the ocean’s surface?
a.
Organisms in the deep sea acquire energy directly from the sun.
b.
Organisms near the ocean’s surface rely on chemosynthesis rather than photosynthesis.
c.
Organisms in the deep sea do not have direct access to sunlight.
d.
Organisms in the deep sea have no means to obtain energy unless they travel to the ocean’s surface.

Once the neural plate edges have fused to become a neural tube, the tissues that were at the edges of the plate now form the __________ region the neural tube. Fill in the blank.

function of graffian follicle
​

Scenario 1:

Genetic engineering can be used to create more productive strains of farm animals used for milk and meat production. By adding genes to an animal’s DNA, the animal can be made to be more resistant to common infections. This can reduce the need to administer large doses of antibiotics to the animals.

Do you think that this type of genetic engineering should be pursued? Explain your answer. (5 points)

What are some possible impacts (positive and negative) of this type of genetic engineering on individuals, society, and the environment? (5 points)


Scenario 2:

Mike was adopted, and his biological family history is unknown. Although he is healthy, he would like some understanding of his genetic makeup, including potential health risks and genes that he could pass on to his children. Mike has heard about commercial laboratories that can compare segments of your DNA to those of people with common hereditary diseases in order to give you some idea of how susceptible you are to the diseases. The results of these types of tests are highly inconclusive. If Mike’s DNA showed that he shares similarities in a segment of DNA with people who have a given disease, his chances of developing that disease or passing it on to his children may be slightly elevated, but they are not 100 percent. These tests can cost more than $2,500 and are not covered by many insurance companies.

Do you think that Mike should undergo the genetic tests? Explain your answer. (2 points)

What are potential pros and cons of having such tests done? (5 points)

Describe how the availability of these genetic tests might affect the frequency of genetic diseases in individuals and populations. (3 points)

what is cyclic and noncyclic photo-phosphorylation​

Match the following Rose Water hyacinth Hydrilla Lotus Pine trees Mango trees A non-flowering plant A flowering plant A floating plant A underwater plant Hot and plain place Cold places Name the following​

The history of life has been punctuated by several mass extinctions. For example, the impact of a meteorite may have wiped out most of the dinosaurs and many forms of marine life at the end of the Cretaceous period. Fossils indicate that plants were less severely affected by this mass extinction. What adaptations may have enabled plants to withstand this disaster better than animals

Explain in detail what caused the population of peppered moths to change from mostly light-colored variations to mostly dark-colored variations in the 1800s. Explain how the peppered moth mutation is an example of natural selection. Explain what would happen to the populations of both variations of peppered moth once the pollution disappeared. Determine which variation of the peppered moth would be more successful in your neighborhood, and explain in detail your reasoning supporting your conclusion. Predict what may happen to the population of peppered moths if they were relocated to a lush, green rainforest ecosystem. How would this impact natural selection and their struggle to survive?

Acidic amino acids have two -COOH and one -NH2 group per molecule. Select the pair that consists of acidic amino acid
a) Aspartic Acid , Glutamic Acid
b) Lysine , arginine
c) Glycine and alanine
d) Both a and b​

Which of the following is the best definition of climate?

1 . The day to day changes in the atmosphere

2. The average weather over a long period of time and over large areas

3. The state of the atmosphere across the world