The____________ produced by photosynthesis was toxic to many early organisms.
a.Carbon
b.Carbon Dioxide
c.Hydrogen
d.Oxygen

Answers

Answer 1

Answer:

I am pretty sure it was Oxygen.

Explanation:

2 billion years ago, when earth was supposedly formed, the atmosphere had slowly been altered by the gradual addition of oxygen, which proved to be fatal to the most common type of organism present on Earth at the time. {Sorry if it isn't correct.}

Answer 2

Answer:

D.Oxygen

Explanation:

Oxygen was proven to be fatal to the most common type of organisms present on the Earth at the time.


Related Questions


PLEASE HELP !! ILL GIVE BRAINLIEST *EXTRA POINTS*..
IM GIVING 40 POINTS !! DONT SKIP :((.

Answers

Answer:

I believe the answer is A.

Explanation:

It wouldn't be B or C and I don't think D really has anything to do with biotechnological research.

--------------------------------------------------------------------------------------------^^

have a good day :))

The gecko is a reptile that has the amazing ability to climb smooth surfaces - even glass. Recent discoveries indicate that geckos stick to smooth surfaces via van der Waals interactions between septae on their feet and the smooth surface. When not selling car insurance, geckos climb smooth surfaces.

a. How is this method of stickiness advantageous to the gecko over covalent interactions?
b. Given that van der Waals forces are among the weakest molecular interactions, how can the gecko's feet stick so effectively?

Answers

Answer:

a) This method of stickiness is advantageous over covalent interactions because it is weak and easily reversible.

b) The feet are equipped with millions of septae which collectively produce a synergistic effect that produces a powerful adhesive effect.

Explanation:

Geckos have their feet studded with tiny hair-like substances called septae, and these substances interact with the surfaces on which the Gecko climbs using weak van der Waals forces to produce stickiness.

a) The van der Waals interactions for the purpose of climbing is of more advantage over the covalent method of interaction because climbing involves a repetitive action of adhesion to the surface and destruction of such adhesion, and this involves the creation and the breaking of the bonds between the two surfaces easily. van der Waals forces being easily broken helps to achieve effective climbing. If the method of interaction is with a comparatively strong bond, the speed of creation and destruction of such bond is reduced, and the effectiveness of climbing is reduced.

b) Although van der Waals forces are weak forces, each foot of the wall Gecko has millions of septae that each create a van der Waals interaction, and the collective interactions produce a powerful adhesion causing the feet to stick effectively.

Why are enzymes described as being like a lock and key?

Answers

Answer:

enzymes are compared to a lock and key as they can activate a chemical process or put that same process into a stop

Explanation:

Which of the following is a trace fossil? *
a mark left by a dinosaur's tail
a mosquito trapped in amber
a mummified plant seed
O a frozen woolly mammoth
which

Answers

Answer:

A. A mark left by a dinosaur's tail.

Explanation:

A trace fossil is the mark or imprint of an animal's body or something it did or left behind, rather than the physical animal itself.

Hope this helps :)

Select the correct answer.
Ships accidentally spread a species of sea urchins to an area of the sea in which they previously didn’t live. The graph depicts the growth trend of native seaweed, a common food for sea urchins, after this invasion. What could ecologists do to curb the trend in the seaweed population?



A.
Eliminate the sea urchins’ competitor.
B.
Introduce more sea urchins.
C.
Introduce a competitor for seaweed.
D.
Introduce a predator for invasive sea urchins.

Answers

I would pick A hope it’s correct

Answer:

D!

Explanation:

Introducing a predator to kill the sea urchins will lower their population and/or make them move away from the area they invaded

Low-carbohydrate diets became popular in the late 1990s and were quickly proclaimed to be a fast and easy method of weight loss. The effectiveness and safety of these diets are dependent on the activity and overall health of the individual as well as the total nutritional content of the diet. However, it is true that in some cases, these diets have been effective. What metabolic effects caused by eating a low-carbohydrate diet can be linked directly to a decrease in fatty acid synthesis and an increase in fatty acid oxidation?

a. release of insulin from pancreatic's cells
b. dephosphorylation of AMPK
c. release of glucagon from pancreatic's cells
d. phosphorylation of AMPK

Answers

Answer:

c. release of glucagon from pancreatic's cells

d. phosphorylation of AMPK

Explanation:

Low-carbohydrate diets (LCDs) stimulate the secretion of glucagon by a decrease in the blood glucose concentration. Glucagon is a key hormone secreted by pancreatic cells in the same way as insulin but in an opposite way. This hormone (glucagon) prevents glucose accumulation as hepatic glycogen, while insulin helps to the accumulation of glucose in the liver as glycogen, thereby acting to reduce hepatic glucose output. Moreover, the AMP-activated protein kinase (AMPK) is a kinase protein that mediates the phosphorylation and inhibition of acetyl-CoA carboxylase (ACC) in order to reduce the synthesis of malonyl-CoA, a key molecule that regulates myocardial fatty acid oxidation.

Give two specific examples where asexual reproduction happens in nature.

Answers

Answer: Bacteria produce asexually, making copies of itself to spread. Plants also produce asexually,  this happens in several ways one way s binary fission. This is asexual reproduction by a separation of the body into two new bodies. Simply copies of the original.

Explanation:

How do we use the Earth’s heat by capturing geothermal energy?

Answers

Answer:People can capture geothermal energy through: Geothermal power plants, which use heat from deep inside the Earth to generate steam to make electricity. Geothermal heat pumps, which tap into heat close to the Earth's surface to heat water or provide heat for buildings. Dose this help?

Explanation:

For aerobic respiration, a variety of substances must be in a state of influx across the inner membrane. Assuming a brain cell in which glucose is the sole energy source, indicate for each of the following substances whether you would expect a net flux across the membrane and if so, how many molecules will move in which direction per molecule of glucose catabolized.

- electrons
-pyruvate
-oxygen
-ATP
-ADP
-Acetyl CoA
-Glyceral-3-phosphate
-NADH
-FADH2
-Oxaloacetate
-Water
-Protons

Answers

Answer:

electrons inflow

pyurvate inflow

oxygen inflow

ATP Outflow

ADP Inflow

Acetyl CoA no net change

Gluceral-3-phosphate no net flow

NADF inflow

FADH2 outflow

Oxaloacetate no net flow

water outflow

proton outflow

Explanation:

Aerobic respiration is the process in which cell get oxygen from within. There is no inflow of oxygen and the movement is minimum. The membrane covering the cell releases the excess oxygen if the initial storage is more than the requirement. This is in the form of outflow in ATP.

why is vachellia nilotica classified as family level

Answers

Answer:

Vachellia nilotica is a flowering plant tree in the family Fabaceae.

Explanation:

I NEED HELP ON THIS QUESTION ^^^^!

Answers

Answer:

The answer is refraction.

Explanation:

Absorption is when no light is reflected back, diffraction is where light bends around a corner, reflection is like taking and shining a flashlight against a mirror, and refraction is like when you put a straw in water and it looks like the straw is not straight.

Answer:

D reflection nga

wala na bang ibang tanong HAHAHHA

Do alligators have complete 360 vision?

Answers

Answer:

yes

Explanation:

compare and contrast nutrition in a guava plant and Rhizopus fungus

Answers

Contrast nutrition in a guava plant and rhizopus fungus:
Guava plant is an autotrophic, but fungi is saprophytic.
Guava is a "tropical fruit" which have nutrients like lycopene, vitamin A and that is also present in "tomatoes, beta-carotene, and cryptoxanthin".
When this fruit received infected with pathogens, there can be a transferred in its nutrient value.
For example: Guava affected by Rizophus arrhizus forced the contents of sugar, protein and ascorbic acid. It raises the phenol level in the fruit.

Question 2 of 10
Psychological perspectives exist:
O A. to address the physical properties of the brain.
B. to explain the science of behavior.
C. so that there can be different ways of looking at psychological
questions.
O D. to enforce one particular way of looking at problems.

Answers

Answer:The correct option is B.

to explain the science of behavior.

Explanation:

This is because psychology perspective is the study of the science of cognitive behavioral. It entails the behaviors of humans both conciously and unconsciously. This perspective deals with the properties of brain. It deals with human ways of thinking, mind and behavior. Therefore it is the science of human behaviors.

which of the following is not a condition that must be made for hardy-weinberg equilibrium 1.no mutation 2.no migration 3.domunant alleles nore frequent than recessive allels 4.large population 5. no natural selection guy please answer this one​

Answers

Answer:

3.dominant alleles more frequent than recessive alleles

Explanation:

To achieve hard-Weinberg equilibrium, certain conditions must be made.

These conditions are:

1. There is noo mutation,

2. Existence of random mating,

3. There should be no natural selection

4. There is the infinite population size

5. No migration

Hence, in this case, the correct answer is option 3, which is not a condition to be made for Hard-Weinberg equilibrium

How is energy stored when ADP is converted to ATP?

Answers

Answer:

Energy is stored in the bonds between the phosphate groups (PO4-) of the ATP molecule. When ATP is broken down into ADP (adenosine diphosphate) and inorganic phosphate, energy is released. When ADP and inorganic phosphate are joined to form ATP, energy is stored.

Explanation:

Hope this helped Mark BRAINLEST!!

why is the moon invisible from earth during a new moon science

Answers

Answer:

Explanation:

During the New Moon the far side of the Moon is illuminated by the Sun, while the side that faces the Earth lies in darkness so the Moon is invisible. As the Moon follows its path from the New Moon position more and more of the Earth-facing side becomes illuminated resulting in the “waxing” phases.

What is the correct order of the cell organization after cellular differentiation

Answers

Answer:

The cell organization hierarchy consists of (in order): cells ⇒ tissues ⇒ organs ⇒ organ systems ⇒ organisms.

Explanation:

I NEED HELP ASSAP


how can you tell whether two magnets will attract eachother, repel eachother, or both

plz explain in a few sentences​

Answers

Answer:

Explanation:

there is a positive side and a negitive side to magnets two of the same side of the magnet will repel oppisites will attract

positive+positive=repel

positive+negitive=atract

Answer:

attract: when two magnets will attract, S and N will be facing each other

repel: when two magnets will repel, S and S or N and N will face each other

both: when two magnets will attract and repel, the magnets won't be placed in the same way. N will be facing the middle of both S and N or S will be facing the middle of N and S

Explanation:

this is what i learned i hope it's right if not i didn't say nothing

2. All living things are made of cells.
True
False

Answers

Answer:

true

Explanation:

WE ARE MADE OF CELLSSSSSSS AND EVERYTHING THAT IS LIVING DOES TOO

Sickle-cell anemia is an inherited disease that affects red blood cells. In people who have this disease, one amino acid is substituted for another amino acid in a blood protein. What causes sickle-cell anemia?

A. Mutation
B. Replication
C. Translation
D. Transcription

Answers

Answer:

A - Mutation.

Mendel's primary contribution to our understanding of inheritance was
al The idea that genes are found on chromosomes
b) Explanation of the patterns of inheritance
c) The discovery of alleles
d) Determining that informations contained in DNA are for protein synthesis​

Answers

Answer:

D.) (Determining that informations contained in DNA are for protein synthesis)

What kind of mutation would occur if a sequence of DNA is changed from ATCGGCTTAACG to ATCGGCTAAACG?

Answers

Answer:

Base substitution mutation

Explanation:

Mutation is the alteration or change that occurs to the sequence of a gene caused by a mutagen (chemicals) or spontaneously-induced. Depending on how the mutation occurs, it is of different types. The mutation shown in this question is as follows:

ATCGGCTTAACG to ATCGGCTAAACG

This type of mutation is called SUBSTITUTION MUTATION. Substitution mutation is a type of mutation that involves the replacement of one or more nucleotide base by another. In this original sequence; ATCGGCTTAACG, the eight base T was replaced by base A in the sequence, hence, it is a substitution mutation.

Compared to small cells, large cells have more trouble doing what

Answers

Answer:

As the cell grows, it faces some issues such as:

• Running out of the nutrients and requirement of growth factors.

• Running out of the space.

• Require appropriate gas exchange.

As compared to the smaller cells, larger cells have more issues in moving the required materials inside and excretory products outside. This is because the ratio of the surface is to volume is turning more and more unbalanced and takes much longer time for the cellular processes to take place.

Explanation:

Simple organisms usually make exact copies of themselves when they reproduce. What do we call this type of reproduction?​

Answers

Answer:

asexual reproduction.

The article mentions the six rules for choosing effective supporting materials. Name the three you feel are the most important and explain why you feel this way. (Site 1)

Answers

Answer:

Don't have to many. I feel like this is one of the most important because if you go on to long about the same thing you will begin to lose your audience and the speech will not be as good anymore. Match the Material to the audience. This is another very important one because if the audience can relate to what you are saying they are going to be way more engaged in what you have to say. Make the purposeful. This is final and 3rd most important rule because what you are saying has to mean something or else what is the point in saying it at all.

Explanation:

Personally don't think this is that good of an essay but I got a 100% on it so it works.

The most important rules include the following;

Saying meaningful words.Matching the material with audience.Be short and concise to prevent ambiguity.

What is an Audience?

These are referred to as  a group of listeners or spectators. It is best to convey information to them in the best possible way.

This is why the important rules which are mentioned above must be followed to prevent confusion.

Read more about Audience here https://brainly.com/question/26120710

the structure labeled A in the figure below is called the

Answers

Answer:

Centromere

Explanation:

Connects sister chromatids

The structure labelled A in the figure is a centromere.

What is a centromere?

The centromere is a region of the chromosome that is constricted. The centromere plays an important role in the division of cells during both the processes of mitosis and meiosis.

The centromere is simply the region of the chromosome where the spindle fibres attach. Therefore, when the spindle fibres attach to the centromere, they pull the sister chromatics in the opposite directions of the cell during cell division.

Thus, at the end of the cell division, each of the daughter cells gets one-half of the chromosome containing identical DNA. The centromere is thought to be the middle region of the chromosome, even though it is often not in the middle. It is simply the region where the chromosomes are most constricted

The centromere separates the chromosome into the P arm and the Q arm. These are simply the names given to the short arm and the long arm of the human chromosome respectively.

Read more about centromere, here

https://brainly.com/question/19339239

#SPJ2

One of the first astronomers to use a telescope was Galileo. Using his telescope he discovered that Jupiter had four moons and each night, the four moons, seen as points of light, appeared to change positions slightly. This observation gave further evidence for what? All BUT ONE could apply.

Answers

Answer:

B. The planets vary in size and composition.

Explanation:

Galileo was an Italian scientist and he was the first person to use a telescope in the field of astronomy. Although, the first telescope was invented by Sir Isaac Newton.

A telescope can be defined as an optical instrument or device which comprises of a curved mirror and lenses used for viewing distant objects i.e objects that are very far away such as stars and other planetary bodies.

One of the first astronomers to use a telescope was Galileo. Using his telescope he discovered that Jupiter had four moons and each night, the four moons, seen as points of light, appeared to change positions slightly. Therefore, this observation gave further evidence that the planets vary in size and composition. The slight change in the position of the moon indicate that planetary bodies have a variation in size and matter (constituent elements) that make them up.

Answer:

b

Explanation:

Why bacteria generally dies in the presence of oxygen ?​

Answers

Bacteria that require oxygen to grow are called "obligate aerobic bacteria". Without oxygen they generally die since these bacteria require oxygen to grow.

Their methods of energy production and respiration depend on the transfer of electrons to oxygen.

Which of the following would NOT be considered an agricultural pest?

an insect chewing holes in leaves
a dog lying among the crops
a rabbit eating growing vegetables
a mole digging tunnels beneath the crops

Answers

Answer:

A dog lying among crop

Explanation:

A insect, and mole are considered pest. And a rabbit eating growing vegetables, well if the rabbit eats the growing vegetables then there not growing.

Answer:  The correct answer is a dog lying among the crops

Explanation:  This answer has been confirmed correct.

A dog is a pet and is not causing damage to the crops. The other three options are all harming the plants (chewing, eating, and digging tunnels).

Other Questions
Consider the following secure channel used by alice and bob to communicateA) if the message number is 64bits long. How many messages could be numbered.B) choose an authentication function for secure channel, the security factor required is 256bits. Explain two ways in which the epic hero of Beowulf has influenced modern storytelling. Be sure to give examples that illustrate your points. If we have a downward-sloping IS curve but a horizontal LM curvea) monetary policy is the most effective way to reduce unemploymentb) fiscal policy is not effective in reducing unemploymentc) neither fiscal nor monetary policy is effective in reducing unemploymentd) fiscal policy is the most effective way to reduce unemploymente) monetary policy can aid fiscal policy in reducing unemployment The maker of Monster energy drinks promotes its brand as a drink for young males who love extreme action and motor sports. If the company decided to promote its product at women's figure skating events, it would be failing to _______.Multiple choice question.a. capture feedbackb. create a consistent brand imagec. create a consistent public messaged. deliver a quality producte. advertise in more than one outlet FILL IN THE BLANK. email ____ involves an email that appears to be legitimate because it includes the name of someone you know, such as your bank, in the messages from line. if tan ( x ) = 5 9 (in quadrant-i), find cos ( 2 x ) = whats this ? i need the answer because i need some better understanding In Unit 1, we learned that one of the purposes of fertilization in animal embryonic development is to restore chromosome number. Which of the following BEST describes what this means? Meiosis produces genetically unique gametes. Fertilization reverses these genetic changes to produce identical zygotes. The chromosome number of a diploid organism is halved during gamete production. When the haploid sperm and egg fuse, diploidy is restored. The chromosome number of a diploid organism results from the fusion of two diploid eggs. Once these nuclei fuse, the chromosomes line up in homologous pairs and separate, resulting in two 2n cells. O Cell differentiation is reversed during gamete production, creating totipotent cells. Fertilization is the fusion of the nuclei of egg and sperm, restoring differentiation to cells. a 200 g ball and a 530 g ball are connected by a 49.0-cm-long massless, rigid rod. the structure rotates about its center of mass at 130 rpm. What is its rotational kinetic energy? As a general principle of gene regulation through operons, regulatory genes encode: ________ A certain second-order reaction (B -> Products) has a rate constant of 1.55 x 10-3 M-1s-1 at 27 oC and an initial half-life of 252 seconds. What is the concentration of the reaction B after one half-life?0.25 M 1.28 M 2.56 M 6.02 M in current .net framework, what assembly must be included in a project to use the soundplayer class? group of answer choices system corelib sound you use_____memory when you answer questions such as ""what is the capital of texas?"" Naomi plotted the graph below to show the relationship between the temperature of her city and the number of popsicles she sold daily: Part A: In your own words, describe the relationship between the temperature of the city and the number of popsicles sold. (2 points) Part B: Describe how you can make the line of best fit. Write the approximate slope and y-intercept of the line of best fit. Show your work, including the points that you use to calculate the slope and y-intercept. (3 points) The bases of the prism below are right triangles. If the prism's height measures 11units and its volume is 130.9 units3, solve for x. Suppose a firm has the following costs:Output (units)Total Cost $1050115212561362147015801692171061812219140(a) if the prevailing market price is $16 per unit, How much should the firm produce?(b) How much profit will it earn at that output rate?(c) if the market price dropped to $12, what should the firm do?(d) how much profit will it make at that lower price? the principle of limiting users access privileges to the specific information required to perform their assigned tasks is known as . A 200-g, 20-cm-diameter plastic disk is spun on an axle through its center by an electric motor. What torque must the motor supply to take the disk from 0 to 2000 rpm in 5.0 s? The system in the human body that deals with thebrain and the (4)_ is the (5)__. Sometimes,medical issues may arise with this system. One type ofexample would be (6)_. When this happens, itrequires a medical professional known as a (7). This type of doctor would need to run tests on theirpatients, like a (8) a union may negotiate limits on workload in order to increase the demand for labor and raise workers' salaries. this practice is known as: