Answer:
Due to presence at early days of the planet.
Explanation:
We only find the remains of single celled organisms in the oldest fossils because the single celled organisms are the organisms that were present in the early days of this planet. These single celled microbes were present about 3.7 billion years ago while on the other hand, the oldest rocks are only a little older i. e. 3.8 billion years so these single celled organisms are considered as oldest fossils on this planet.
Which of the major tectonic plates is composed mainly of oceanic lithosphere?
Answer:
A tectonic plate (also called lithospheric plate) is a massive, irregularly shaped slab of solid rock, generally composed of both continental and oceanic lithosphere. Plate size can vary greatly, from a few hundred to thousands of kilometers across; the Pacific and Antarctic Plates are among the largest.
A student examines a periodic table.
Which inferences about sodium (Na) are true?
Answer:
true c this is the answer
hello help please i’ll mark brainliest!!!
Answer:
the secone option
Explanation:
i just need one more brainliest thanks<3
Answer: The third one
Explanation: It is the third one because scientist have been talking about how there are billions of galaxy's in our universe.
Question 6
Thermal is to heat as _____
is to water.
A. Absorb
B. Dilute
C. Waste
D. Drain
Answer:
drain
Explanation:
thermal is to hear as drain is to water
Answer:
thermal is to heat as dilute is to water
how many codons specify 5 amino acids?
Answer:
20, Im not completely sure tho
Explanation:
If 22% of a DNA sample is made up of cytosine, C, what percentage of the sample is made up of adenine,
A?
Answer:
28% of Adenine
Explanation:
Chargaff's Rule states that A = T and C = G
Because of that, the sample must have the equation:
A + C = T + G
G must have the same amount as C so,
A + .22 = T + .22
Both sides of the equation must equal each other by .50, so .50 - .22 = .28
.28 x 100 = 28%
If 22% of a DNA sample is made up of cytosine, C, the percentage of the sample is made up of adenine, A is 28%
What is DNA?The DNA sequence is the sequence or pairing of DNA bases. RNA and DNA both are genetic materials and both are made up of nucleic acids made up of deoxyribose acid and iron is made up of ribonucleic acid.
DNA and RNA both contain four bases that are joined with hydrogen bond RNA contain uracil in the place of thymine and DNA contain timing all other bases are the same.
Chargaff's Rule states that A = T and C = G
Because of that, the sample must have the equation:
A + C = T + G
G must have the same amount as C so,
A + .22 = T + .22
Both sides of the equation must equal each other by .50, so .50 - .22 = .28
.28 x 100 = 28%
Therefore, the percentage of the sample is made up of adenine, A is 28%
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A student crested a model to show the flow of energy in a terrestrial ecosystem.
Which of the following correctly describes the way energy enters and leaves the ecosystem?
A Energy enters the ecosystem as sunlight, which is used by plants to produce sugars Energy leaves the ecosystem as heat from plants, herbivores, carnivores, and decomposers
B Energy enters the ecosystem from decomposers and is used by plants to produce sugars Energy leaves the ecosystem during cellular respiration
C Energy enters the ecosystem when it is transferred from the herbivores to the plants. Energy leaves the ecosystem as heat from plants, herbivores, carnivores and decomposers
D Energy enters the ecosystem as sunlight, which is used by plants to produce sugars. Energy leaves the ecosystem as mineral nutrients
The flow of energy in the terrestrial ecosystem is initiated by the sun and its flows to plants and then animal life and finally reaches the decomposers. Thus the option A is correct.
What is an ecosystem?An ecosystem is an ecological unit and its function is to balance the flow of energy in the environment. The flow of energy is unidirectional and as energy flow in one direction, it cannot be destroyed completely as it changes its form.
The energy that is received from the sun is transferred to the green plants, they include this energy to animals that are producers to consumers that include primary consumers and secondary consumers to decomposers, and then this energy leaves the system.
Find out more information about the ecosystem.
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The three domain system resulted in dividing all life into three ____, called ___, ___, and ____.
Answer:
systems
Archaea
Bacteria
Eukarya
Explanation:
The three domain system resulted in dividing all life into three systems, called Archaea, Bacteria, and Eukarya.
Hope this helps! :)
Explain what other steps need to be taken to demonstrate that each of these factors is needed for photosynthesis.
light
Why does sodium and potassium ions need a protein pump to pass through the cell membrane?
A. The ions have a charge and cannot pass directly through the cell membrane.
B. The ions are moving against the concentration gradient.
C. Energy is needed to move the ions.
D. All of the above.
Cell membrane have been the selective membrane that allows transportation. Sodium and potassium ions need a protein pump as they are charged particles that move against the gradient and need energy. Thus, option D is correct.
What is active transport?Active transport has been the way to move ions and molecules inside and outside the cell membrane. This system of transportation requires energy as the ions move from low concentration regions to the region of the higher electrochemical area.
The sodium and potassium pump needs proteins and energy to move the ions as the inside of the cell is rich in potassium and the exterior is rich in sodium ions. The charged ions moving against the concentration cannot enter the cell without energy and protein pumps.
Therefore, option D. all of the above statements are correct.
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HELP ONLY IF YOU KNOW PLEASE!!
A species of beetle can be either black or brown in color. The beetle's color is determined by a single gene, and black is recessive to brown. The soil in the area has become darker and closer in color to the black beetles. Which of the following will most likely occur?
Selective pressures will decrease the number of brown beetles.
Selective pressures will increase the number of brown beetles.
Selective pressures will decrease the number of black beetles.
The overall size of the beetle population will continue to decrease over time.
Answer:
the first option
Explanation:
As the soil gets darker, brown beetles become easily recognised by predators (like birds) and will be eaten. Black beetles however, are better camouflaged and will less likely be spotted by the birds. Black beetles will survive and interbreed, allowing the recessive allele to be passed on to upcoming generations.
Selective pressure is what makes the genetic pool shift toward a particular genotype with a particular phenotype (recessive black in this case) that gives the new generations a selective advantage. They're more likely to survive and reproduce. Survival of the fittest.
Genotype- the genetic makeup of an organism (eg: the recessive gene for black; bb)
Phenotype- physical feature of an organism as determined by the genotype (the colour black)
Selective pressures will increase the number of brown beetles. The correct option is 2.
What is Selective pressure?Any factor that reduces or increases reproductive success in a subset of a population may exert evolutionary pressure, selective pressure, or selection pressure, thereby driving natural selection.
Selection pressure can be defined as a force that causes an organism to evolve in a specific direction.
It is not a physical force, but rather an interaction between natural variation in a species and environmental factors that causes certain forms to have an advantage over others.
A beetle species can be either black or brown in color. A single gene determines the color of the beetle, and black is recessive to brown.
The soil in the area has darkened and taken on the color of black beetles. Brown beetle populations will increase as a result of selective pressures.
Thus, the correct option is 2.
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What do plants use to form
glucose?
Answer: Plants, unlike animals, can make their own food. They do this using a process called photosynthesis . During photosynthesis, plants produce glucose from simple inorganic molecules - carbon dioxide and water - using light energy.
how barometer helps in agriculture
______ contains many wavelengths and is similar to sunlight at noon on a bright day.
A. Ultraviolet
B. White light
C. infrared
D. Visible light
Answer:
It should be D.
Explanation:
I hope this helps
A football player kicks a ball 6.5 meters how much time is needed for a ball to travel this distance if it's speed is 22 m/s
Answer:
.3 m/sec
Explanation:
Diffusion is the movement _____.
of molecules to an area of lower concentration
of molecules through the cytoplasm of a cell
of water through a selectively permeable membrane
of molecules to an area of higher concentration
Answer:
of molecules to an area of lower concentration
Why do nervous system
responses tend to be more rapid
than endocrine system responses
Select ALL of the following that are directly involved with making a protein
Ribosome
Cell Membrane
DNA
Cytoplasm
Cell Membranes,Ribosome, Cytoplasm are used to make protein
Explanation:
Proteins are formed in a condensation reaction when amino acid molecules join together and a water molecule is removed. The new bond formed in protein molecules where amino acids have joined (-CONH) is called an amide link or a peptide link.
hope it will help you
What does it mean when we say that DNA replication is semiconservative ?
Answer:
Basically, when people say that DNA replication is semi-conservative they are saying that two identical copies are being made from the original DNA strand.
Explanation:
The two new strands contain one side of the original DNA and another side of synthesized pair.
What occurs during glycolysis?
Answer:
Glycolysis is the process in which one glucose molecule is broken down to form two molecules of pyruvic acid science my fav class btw thats how i know it
Explanation:
Groundhogs sometimes eat garden vegetables such as these peppers. Once the pepper has been eaten and digested, the seeds exit the animal through its waste. In what way does this help the pepper plants?
A large industrial company manufactures paper products such as paper towels and napkins using wood pulp. Which of these BEST describes why wood is considered to be a 'renewable' resource?
Answer: The question is incomplete because the options were not given but the options has been gotten from another website.
Here are the options.
a. Wood is routinely recycled to make new wood-based products.
b. Wood products can be manufactured from different tree species.
Eliminate
c. Wood may be replenished by planting new trees to replace those being used.
d. Wood products can be manufactured using various other materials such as plastics.
The correct option is c.
Wood may be replenished by planting new trees to replace those being used.
Explanation:
This is because wood is a Renewable resource because Renewable resources are resources that can be replenish or reproduce again after usage either by naturally producing another one. Theses resources are not exhausted because they can naturally be reproduce again. Wood is a Renewable resources because new ones are planted to replaced the used ones.
please help! i dont really get this at all
Answer:
The slope between the red points is 2/4 (simplified it is 1/2). The slope between the green points is 4/8 (simplified it is 1/2). This shows that by taking ANY two points on the line, you will find the same slope.
what are the two main types of chemical bonds?
Answer:
Chemical bonds include covalent, polar covalent, and ionic bonds. Atoms with relatively similar electronegativities share electrons between them and are connected by covalent bonds. Atoms with large differences in electronegativity transfer electrons to form ions. The ions then are attracted to each other.
Two of the strongest forms of chemical bond are the ionic and the covalent bonds. Chemical bonds form between two atoms, each with its own electron environment.
Hope it helps!!!
Answer:
the two main types of chemical bonds are:
ionic bonds and covalent bonds.
What percentage of Americans use solar power ?
Answer:
66.7 percent.
Explanation:
what % of the brain is made up of water?
Answer:
about 73%
Explanation:
Answer:
About 75% of the brain is made of water.
The diagram shows the life cycle of a fern,
What does stage 2 show?A. A gamete-producing fern plant is flat and shaped like a heart.
B. A zygote forms when a sperm fertilizes an egg cell.
C. A mature spore-producing fern plant has fronds and produces
spores
D. A spore grows into a mature gamete-producing plant,
Answer:
the correct answer is D!
A spore grows into a mature gamete-producing plant.
Explanation:
hope this helps :)
A spore grows into a mature gamete producing plant is best describe the life cycle of fern.
What is the life cycle of fern?The life cycle of the fern has two different stages such as sporophyte and gametophyte. The sporophyte stage which releases spores whereas gametophyte stage which releases gametes. Gametophyte plants are haploid whereas sporophyte plants diploid. This type of life cycle is known as alternation of generations.
So we can conclude that a spore grows into a mature gamete producing plant is best describe the life cycle of fern.
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When the environment acts for or against one extreme characteristic, this is an
example of which category of natural selection?
Answer:
Directional selection
Explanation:
occurs when natural selection favors one extreme of continuous variation. Over time, the favored extreme will become more common and the other extreme will be less common or lost.
Deforestation leads to environmental imbalance. Give reason.
Answer: Well, deforestation is cutting down trees, and many arboreal animals live in those trees. So if they have no proper shelter, they would have no place for personal activities such as breeding, feeding etc. And without those important activities that they have to do everyday, the population of arboreal animals will keep on decreasing until they go extinct. Though that's not the only problem. The herbivores won't get anything to eat, hence not letting the omnivores or carnivores get their food. As you can see, deforestation can create a huge environmental imbalance.
suppose you find a paper clip stuck to a magnet you pull off the paper clip and move it to a short distance away from the magnet what happened to the magnetic Force between the magnet and the paper clip A. it disappears B. it gets stronger C. it gets weaker D.it stays the same
Answer: C
Explanation: it gets weaker because there not as close together