After observing tadpoles swimming in the water, you could infer that all amphibians have gills.

True or false

Answers

Answer 1

Answer:

All amphibians are born in the water. When they are young, they have gills to take oxygen from the water. When they grow up, most develop lungs so they can breathe air and live on land.

Explanation:


Related Questions

What is the meaning of life and why do we live

Answers

In my mind the meaning of life is just to have fun and live it to the fullest, and for why do we live, well if your asking like what created us or how we came to be that I don't know but if your asking why to keep going then I'd say just for the shower thrill of not knowing what will happen tomorrow, could be a normal day, could be a bad one, and heck you could end up getting $1mil, you just never know

Over the last 540 million years, icecaps covered at least one of the Earth’s poles during three intervals. what are those 3?

Answers

The fluctuation in the time and intensity of Light is the primary cause of the Ice Age, or the prolonged period of harsh winter. Because the sun's light has such a strong impact on the atmosphere and general environment of the earth's surface.

After a short period of time, the Andean-Saharan cold age (460 to 430 million years ago) led to the widespread extinction of organisms. The majority of the earth's surface was covered by vegetation. As it was also stated that the subsequent ice age was brought on by this large amount of plants. As it round the earth's poles.

The Karoo Ice Age, which lasted from 360 to 260 million years ago, functioned quite similarly to the present.

We are currently experiencing this ice age, which started when Antarctica froze over 14 million years ago. because ice caps cover the earth's poles.

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Engineers who work for a museum would like to make a model of a blue
whale using a scale of 1:20. If a blue whale averages 20 m in length, how long
will the model be?
O A. 1 m
OB. 10 m
OC. 400 m
D. 20 m

Answers

C. I did it on e2020

Sahana used to use fertilizer frequently on her farm in the United States, but now she uses less fertilizer. What does this MOST likely indicate?

Question 10 options:

She has a harder time obtaining fertilizer now than in the past.


She has decreased the number of acres that receive fertilizer.


The fertilizer she uses now is more efficient than what she used in the past.


She is decreasing the number of acres that she is planting because it isn't profitable anymore.

Answers

Sahana used to use fertilizer frequently on her farm in the United States, but now she uses less fertilizer. This most likely indicate that She has a harder time obtaining fertilizer now than in the past.

Fertilizers that are used for agriculture purpose are significant source of nutrient for plants , but when it is used in higher quantity it can cause water pollution. fertilizers reduces quantity of oxygen in the water that can make survival of marine life very difficult .

Fertilizers used in agriculture are main source of nutrient pollution to water. Components like nitrogen and phosphorus escape from agricultural fields and collects in water bodies becomes the largest sources of pollution to coastal zones across the United States.

Hence, A is correct option

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What is soil pollution?
A. Pollutants of any kind that end up in the soil and
affect plants' ability to grow.
B. Pollutants that end up in the air from plants in
polluted soil.
C. Pollutants in the soil that evaporate into the air.
D. Pollutants that come out of soil into water.

Answers

Answer: A

Explanation: Soil pollution is defined as the presence of toxic chemicals (pollutants or contaminants) in soil, in high enough concentrations to pose a risk to human health and/or the ecosystem. In the case of contaminants which occur naturally in soil, even when their levels are not high enough to pose a risk, soil pollution is still said to occur if the levels of the contaminants in soil exceed the levels that should naturally be present. Soil pollution affects plants, animals and humans alike. While anyone is susceptible to soil pollution, soil pollution effects may vary based on age, general health status and other factors, such as the type of pollutant or contaminant inhaled or ingested. It mainly affect's the plants ability to grow.

The table below shows three enzymes found in the human body and the pH of their locations.
Enzyme Body part pH
Ptyalin Mouth 6.5 - 7
Pepsin Stomach 1.0 - 3.0
Trypsin Small intestine 7.5 - 9.0
How will the activity of pepsin change after it moves with the food from the stomach to the small intestine?
Choose 1 answer:
Choose 1 answer:

(Choice A)
A
It will increase as the pH increases.

(Choice B)
B
It will slow down because the environment is too basic.

(Choice C)
C
It will decrease because the pH of the small intestine is similar to that of the stomach.

(Choice D)
D
It will adapt to the new environment and continue to work at the same rate.

Answers

B. It will slow down because the environment is too basic.

As the food move from the stomach to the small intestine the activity of pepsin will slow down because the environment is too basic.

Pepsin- Pepsin is a stomach digestive enzyme used to break down proteins in food that has been consumed. Pepsin is produced by the main cells of the stomach as pepsinogen, an inactive zymogen. The stomach's lining's parietal cells release hydrochloric acid, which reduces the pH of a stomach.

Parietal cell- The biggest cells in such glands are called parietal cells, and they are found inside the fundus & body of the stomach. They develop from immature progenitor cells inside the gland isthmus, travel upward into the pit area, and finally migrate downward toward the gland base.

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What would happen if there was no mutation?​

Answers

Answer:

​ Only when DNA changes are carried in egg and sperm cells are they passed to the next generation. Believe it or not, a certain amount of sloppiness is built into the system. Without mutation there would be no variation, and without variation there would be no evolution.

Explanation:

Answer: The short answer is, you could look at it as a bad or a good thing. I’ll explain. If you look at the advances in medicine from, say, 1901 to 2021, you could probably answer your question. Medicine hasn’t stopped all mutations (yet), but the fact is, we are definitely changing the course of natural selection. Take a person diagnosed with benign congenital skin cancer. 100 years ago, that could have been a death sentence, because though surgeons may try to remove the mass, there was not a good enough understanding of microscopic organisms for the prognosis of surgery to be very desirable because of infections. With modern surgery, this person with skin cancer could have the cancerous cells excised in a sterile environment and live on. So even though we haven't removed the cancerous mutation, in a way we have done something equivalent: we've removed its negative effect on the person’s body. It could be argued that this is a bad thing; we are allowing that cancer gene to propagate into later generations if the person with the now-excised cancer was to have a child. There are also worries in the media about an aging population, which has been purported to have a potential doomsday outcome. But for obvious reasons, the ability to remove a tumor without infection is also a good thing. So, medicine could be considered either good or bad or both. Extending that, if you agree that removing a gene’s negative effect is similar to removing the gene itself, then having a mutation-free world would be either good or bad or both.

Following this, if there were no mutations at all, I actually don't think the changes would be any more drastic than the changes we have seen resulting from modern medicine. A lack of genetic disorders would not end death, remember, there would still be death from things like traumatic injury and heart disease. Also keep in mind that in a mutation-free world, biodiversity would be preserved because of meiosis.

So I suppose whether an absence of mutations is good or bad depends on how much weight you give to worries of an aging population because of modern medicine versus how much you appreciate the security of a longer and healthier life for you and your family.
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for my science experiment (IB program. Internal Assessment) i am testing which method leads to the most seed germination. i have 2 independent variables: hydroponic system and regular soil. what would a possible control group be?​

Answers

Answer:

regular soil because

from small classes we learn that germination is nice for plqnts


If a mutation occurs in a gene that codes for a protein, what might happen to that protein after the mutation has occurred?
a.
The gene and mRNA do not change, but the protein does.

b.
The mRNA changes but the amino acid sequence does not.

c.
The protein might have different amino acids because the mRNA had different codons.

d.
Nothing - mutations only cause changes in the DNA.

Answers

The gene and mRNA do not change, but the protein does. Option A.

When the mutated sequence is translated into protein the resulting protein is incomplete and shorter than normal. As a result, most nonsense mutations result in non-functional proteins. A genetic variant can prevent one or more proteins from functioning properly. By changing the instructions of genes to make proteins.

The variant may cause the protein to malfunction or not be produced at all. The mutation is the process that causes a permanent change in the DNA sequence. Changes in a gene's DNA sequence called mutations can change the amino acid sequence of the protein the gene encodes, but this is not always the case. Coding region mutations can have very different effects on an organism's phenotype. Some mutations in this region of DNA and RNA can result in beneficial changes.

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Which
process IS responsible for causing menstruation?
A.
breakdown of the corpus luteum
fertilization of the egg
implantation of the egg in the endometrium
D.
rupture of a follicle
in the ovary
® E.
repair of the endometrial lining

Answers

Answer:

e

Explanation:

Answer:

d. rupture of a follicle in the ovary

Explanation:

The atomic number of carbon is 6. How many electrons does an atom of carbon have if it is represented by the symbol
shown below?
12C²-
O 5 electrons
O 6 electrons
O 7 electrons
O 11 electrons

Answers

Answer:

It has an atomic number of 6. That means a carbon atom has 6 protons, 6 neutrons, and 6 electrons

The ability to roll your tongue is caused by a dominant gene (R). If you can't roll your
tongue, you are a non-roller and must be homozygous recessive (rr). If our trait of interest
is INABILITY to roll your tongue, in a Pedigree, A homozygous dominant female is
represented
by a(n):
A)Unfilled square
B)Unfilled circle
C)filled square
D)filled circle

Answers

The ability to roll the tongue is due to a dominant gene (R). If you cannot roll your tongue, you must not have curly hair and be homozygous recessive (RR). If the trait we're interested in is the inability to roll the tongue, then homozygous dominant females are represented by (n):D) filled circles on the pedigree.

Homozygous for a particular gene means that you inherited the same mutation. This is another heterozygous genotype in which the allele is specific. People with recessive tendencies, such as blue eyes or red hair, are consistently homozygous for this gene. If the two mutations are different, they are heterozygous for that gene.

For example, being heterozygous for hair color means having one red hair allele and one brown hair allele. The relationship between the two alleles affects the changes expressed. Homozygous and heterozygous are phrases that can be used to describe pairs of alleles. People who carry the same allele (RR or rr) are called homozygous. Just as a human organism with a unique allele (Rr) is said to be heterozygous.

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A 25kg child resting at the top of a 2 meter slide has how much potential energy?

Answers

980 Joules of potential energy

Which energy has potential?

The energy that a thing retains due to its position in relation to other objects, internal tensions, electric charge, or other elements is known as potential energy in physics.

Common types of potential energy include the gravitational potential energy of an item, the elastic potential energy of a stretched spring, and the electric potential energy of an electric charge in an electric field.

Potential energy was first used by Scottish engineer and scientist William Rankine in the 19th century, however it has roots to the idea of potentiality put out by the Greek philosopher Aristotle.

The child has 50 kg * 2 m * 9.8 m/s^2 = 980 Joules of potential energy.

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Which of the following is following mechanisms of evolution is associated with reproductive success?



Bottle neck effect


Natural selection


Mutation


Founder Effect

Answers

Natural selection is the most important mechanism of evolution associated with reproductive success (Option 2).

What is natural selection?

Natural selection is the main evolutionary mechanism by which species adapt to changes in environmental conditions. This process (natural selection) is based on the differential survival and reproduction rate of organisms that better fit environmental conditions.

Therefore, we can conclude that natural selection represents the main evolutionary process for which a species can survive and differentially reproduce in a given environment, thereby confirming an adaptive advantage to the certain individuals in a population in nature

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Need this answer quick as possible

Answers

a. Combination of alleles in BbEE = BE and bE

b. Combination of alelles in BBee = Be only

c. Offspring's genotype = BBEe and BbEe

d. Offspring's phenotype = brown and free earlobes

e. The probabilities are 100%, 0, 0, and 0 respectively

Dihybrid crossing

The man's genotype is BbEE while the woman's genotype is BBee.

Combination of alleles in BbEE = BE, BE, bE, and bE

Combination of alleles in BBee = Be, Be, Be, and Be

Crossing the man and the woman:

              BbEE   x   BBee (see the Punnet's square attached)

Offspring's Gentoytpes:

BBEe BbEe

Based on the assumption that brown and free earlobes are dominant, the phenotype of all of the offspring is brown and free earlobes.

Probability of brown and free earlobes = 100%Probability of brown and attached earlobes = 0Probability of blonde and free earlobes = 0Probability of blonde and attached earlobes = 0

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The following diagram shows a macromolecule produced by cells.

(Picture below)

During which process is this produced?

Question 5 options:

photosystem I


light independent reactions


light dependent reactions


photosystem II

Answers

The given diagram is produced during the light independent reactions.

The given molecule diagram is the Glucose molecule.

Light Independent Reaction- The photochemical process of photosynthesis involves a number of light-independent biochemical events that result in the formation of organic compounds from carbon dioxide. This metabolic pathway is propelled by the energy released from the ATP created during the light reactions.

Photosynthesis- All green plants use the biological process of photosynthesis to create their own nutrition. Photosynthesis requires carbon dioxide, water, and solar energy. Oxygen is a byproduct of this activity.

Light-dependent reactions & light-independent reactions are the two phases of photosynthesis. Daytime events involve light-dependent processes, often known as light reactions. The dark reaction or Calvin cycle are other names for the light-independent process.

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In the experiment shown below, if the temperature of the room rose, what would happen to the time taken for the litmus paper to turn blue?

Answers

The time taken will be more for the litmus paper to change its color from red to blue.

What is the use of litmus paper?

An inspector can measure the acidity or basicity of a solution by using litmus paper, which turns red at pH levels below 5 and blue at pH levels above 8. Using litmus paper, which compares minute color variations to a color chart to identify pH levels, allows for more accurate pH determinations.

The rise in temperatures favors the acidic pH of the litmus paper. A solution's molecular vibrations increase as its temperature rises, which causes the solution to ionize and produce H+ ions. Acidic behavior increases with the amount of H+ ions. The pH level of the solution alters as a result of temperature variations. As a result, the pH drops as the temperature rises.

Hence, the litmus paper takes more time to turn blue in color due to the temperature rise.

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The correct answer is it will take some more extra time for litmus paper to turn blue.

How pH affects with temperature?

pH decreases with increase in temperature.

• It means temperature and pH value both are inversely proportion.

• Neutral is 7. Less than 7 of pH value it is acidic and more than 7 then it implies it is basic.

•  To support our answer added one image for illustration below

From above table we can conclude as temperature grows pH value will decrease.

Hence, it will take some more time for litmus paper to turn blue.

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2) State three economic importance and mode of infection of cestode and trematode​

Answers

Both Cestode and trematode have mode of infection as consumption of contaminated food. Cestode is acquired by ingestion of meat from hosts and trematode is via contaminated food like raw fish, crustaceans, etc.

What are Cestode’s economic implications?

These tapeworms are the least helpful creatures. But these tapeworms also have a very limited economic impact. These tapeworms contribute to the harvesting of soil’s increased fertility through a natural process. These worms function as organic fertilizers.

What is the Cestode’s mode of infection?

Meat from intermediate hosts is frequently consumed in order to acquire adult cestodes. Eggs of origin can cause an extraintestinal infection with larvae. Identification of eggs and segments (proglottids) in feces is used to diagnose an adult cestode infection.

What method does a trematode use to spread infection?

Humans become infected by foodborne trematodes after eating tainted food (raw fish, crustaceans or vegetables. Infection can induce severe liver and lung illness, which together are thought to account for 2 million years of life lost to disability and death globally each year.

What distinguishes a trematode from a cestode?

Cestodes lack a digestive tract and have a tape-like, segmented body.  Trematodes have an imperfect digestive system and resemble leaves. Cestodes typically need two hosts, whereas trematodes typically need three, to complete their life cycles.

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HOW WOULD YOU ENSURE YOU HAVE VALID DATA? 6TH GRADE SCIENCE

Answers

How can scientific validity be ensured?

More variables under control, better measurement methods, more randomization to avoid sample bias, experiment blinding, and the addition of control or placebo groups can all help an experiment's validity.

What determines the reliability of scientific data?

How well a method measures what it is supposed to measure is known as its validity. When a study's findings are highly valid, it means that they accurately reflect the genuine features, traits, and variations in the physical or social reality. High dependability is one sign of a valid measurement.

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I need help with this please

Answers

The human body have an estimated amount of 600 to 650 muscles. There are three main types of muscles (skeletal, smooth and cardiac). Therefore, the correct alternative is the one with the number 650.


Specialized sweat glands associated with the production of earwarx are known as
_____ glands

Answers

Specialized sweat glands associated with the production of earwax are known as ceruminous glands.

What is ceruminous gland and how does it produce wax?Ceruminous glands are the glands responsible for the production of ear wax in the ear.Ceruminous glands are present in the external auditory meatus of the middle ear and is responsible for the production of wax.Ceruminous glands does the job along with sebaceous glands .Though the answer to the question could be simply sebaceous gland but it is ceruminous gland along with sebaceous gland .The area in the outer ear canal have these glands producing ear wax which is natural phenomena.Along with it the apocrine glands are also responsible for wax and sweat.

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Construct a basic pathway for blood flow in a human body using heart, arteries and veins.

Answers

Blood is forced into the pulmonary artery by the ventricle when it contracts, passing via the pulmonic valve. Blood is transported through the pulmonary artery to the lungs, where it "gathers" oxygen. It then exits the lungs and travels through the pulmonary vein back to the heart. Blood flows into the left atrium.

QUESTION 7
The process by which a species or ecosystem changes the environment in a way that leads to another species being able to
move in and become dominant.
O Mediation
O Niche building
O Facilitation
O Microclimate adjustment

Answers

Niche building is the process by which a species or ecosystem changes the environment in a way that leads to another species being able to move in and become dominant.

Niche- A niche is a position or location that is highly suitable for somebody or something, often because it is very particular and unique from others. A position and interest that enables something or someone to thrive in a specific context is frequently referred to as a niche.

Ecosystem- An ecosystem is a region where a bubble of life is created by plants, animals, as well as other organisms interacting with the weather, environment, and other factors. Abiotic variables, or nonliving components, coexist with biotic components in ecosystems. Plants, animals, as well as other species are biotic factors.

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Spiders, scorpions, and ticks belong to the class:
a. Isoptera.
c. Chordata.
b. Crustacea.
d. Arachnida.

Please select the best answer from the choices provided

A
B
C
D

Answers

Answer:

D. Arachnida

Explanation:

Each of these specimens have 8 joint-legs.

Which would best model the motion of P waves?

Answers

Answer:

pulling one end of a spring and releasing it

Pls help me all u have to do is tell me what is wrong in the cell that is causing this to happen

Answers

Plants would not able to grow nutrients, small molecules would able to move through plasma membranes

Why are my plants not developing quickly?

either too little or too much fertiliser is added:

The soil eventually becomes deficient in nutrients as a result of the plant absorbing the earth's nutrients over time. The rate of development may be slowed down if fertilisers (natural or organic) are not occasionally provided.

Proteins will not be transported through active trantransportsport , hypertonic condition when too much water in the cell and cause it burst, The dyeing of cells called necrosis , only glucose is converted into food source .

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Which of the following refers to the brightly colored parts of the plant located just inside the sepal?

stomata

seeds

carpel

petals

Answers

The bright-colored parts of the plant located just inside the sepal are petals. The correct option is d.

What are petals?

Petals are the bright and different-colored and designer parts of a plant. They are present in the flower. Petals are the attractive part of the plant and their beautiful color attracts insects and birds and helps in pollination.

Sepals are the green-colored part that is present outside the petals. They cover the petals inside it when they are small. Seeds are the small hard part of the plant.

Therefore, the correct option is d. petals.

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Answer:

petals

Explanation:

got it right on edge 2022

A company is creating a new mosquito repellent, and needs to figure out how much is
needed to stop mosquito bites. They find volunteers from the nearby college. Each
person is given either 1mL, 2mL, or 3mL of the repellent to rub on their arm. Some
volunteers are given no repellent. Each person is then put in a room with mosquitoes for
10 minutes. Numbers of bites are measured for each volunteer.


What is the independent variable

What is the dependent variable

And what is the control group

Answers

A company is creating a new mosquito repellent, and needs to figure out how much is
needed to stop mosquito bites. They find volunteers from the nearby college. Each
person is given either 1mL, 2mL, or 3mL of the repellent to rub on their arm. Some
volunteers are given no repellent. Each person is then put in a room with mosquitoes for
10 minutes. Numbers of bites are measured for each volunteer.

Review research and related literature on immigrant populations in the rural/ global environment

Answers

The impact of immigrant population in the rural and global environment is degradation in human ecology.

What is immigrant population and how the rural area and global environment are effected by it?The population that are migrated from the native place to the place where the population is either sent or migrated for some reason.There are lot of problems showed by the immigrant population as in the context of human ecology.Human ecology is getting disturbed by this migration as the population is getting more in rural regions of our country in compare to urban areas.Poor is getting poor and rich getting richer, to maintain the sustainable balance in the environment , it should be taken into concern.

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If a tractor has a mass of 234 what is the acceleration?

Answers

The acceleration of the tractor is a = F/234.

How to find acceleration?

Newton's second law of motion states that an object's acceleration is equal to its mass divided by the net force acting on it, or a = F m.

When an object's mass and the net force acting on it are known, its acceleration can be calculated using this equation for acceleration.

The SI units for acceleration are m/s2, meters per second squared, or meters per second per second, which expresses the change in velocity in meters per second over a period of time.

There is a different relationship between mass and acceleration. The relationship is inverse.

In an inverse connection, one variable rises as the other one falls.

An item will accelerate with a given force less slowly the more mass it has.

a = F/m

a = F/234

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