Answer:
Advanced forms of life existed on earth at least 3.55 billion years ago. In rocks of that age, fossilized imprints have been found of bacteria that look uncannily like cyanobacteria, the most highly evolved photosynthetic organisms present in the world today. Carbon deposits enriched in the lighter carbon-12 isotope over the heavier carbon-13 isotope-a sign of biological carbon assimilation-attest to an even older age. On the other hand, it is believed that our young planet, still in the throes of volcanic eruptions and battered by falling comets and asteroids, remained inhospitable to life for about half a billion years after its birth, together with the rest of the solar system, some 4.55 billion years ago. This leaves a window of perhaps 200-300 million years for the appearance of life on earth.
divine interventionThis duration was once considered too short for the emergence of something as complex as a living cell. Hence suggestions were made that germs of life may have come to earth from outer space with cometary dust or even, as proposed by Francis Crick of DNA double-helix fame, on a spaceship sent out by some distant civilization. No evidence in support of these proposals has yet been obtained. Meanwhile the reason for making them has largely disappeared. It is now generally agreed that if life arose spontaneously by natural processes-a necessary assumption if we wish to remain within the realm of science-it must have arisen fairly quickly, more in a matter of millennia or centuries, perhaps even less, than in millions of years. Even if life came from elsewhere, we would still have to account for its first development. Thus we might as well assume that life started on earth.
How this momentous event happened is still highly conjectural, though no longer purely speculative. The clues come from the earth, from outer space, from laboratory experiments, and, especially, from life itself. The history of life on earth is written in the cells and molecules of existing organisms. Thanks to the advances of cell biology, biochemistry and molecular biology, scientists are becoming increasingly adept at reading the text.
An important rule in this exercise is to reconstruct the earliest events in life's history without assuming they proceeded with the benefit of foresight. Every step must be accounted for in terms of antecedent and concomitant events. Each must stand on its own and cannot be viewed as a preparation for things to come. Any hint of teleology must be avoided.
Anyone know the answer?
Answer:
the answer c. is correct
Explanation:
During DNA replication, the two parental DNA strands must be separated so that both strands can be copied. The resulting structure known as 'replication fork' is generated by helicase enzymes that break hydrogen bonds that hold DNA strands together, thereby the two strands of the DNA double helix uncoil at a specific location called the origin. DNA replication always proceeds in 5' to 3' direction. In consequence, a new DNA strand referred to as 'leading strand' is continuously synthesized because this strand grows in the same direction (5' to 3' direction) of the replication fork's movement, while other new DNA strand referred to as 'lagging strand' is synthesized discontinuously in short pieces called Okazaki fragments.
• For which disease of the following a student of High school can be disabled in locomotion?
a) Ectodermal displasia
c) Myopia
b) Muscular Dystrophy
d) Haemophilia
Answer:
B
Explanation:
a group of diseases that cause progressive weakness and loss of muscle. Abnormal genes interfere with the production of proteins needed to form healthy muscles. There are many forms of Muscular Dystrophy.
Which process requires the absorption of sunlight?
Answer:
photosynthesis requires the absorption of sunlight
state 5 processes involved in water cycle
Answer:
There are five processes at work in the hydrologic cycle: condensation, precipitation, infiltration, runoff, and evapotranspiration. ... Together, these five processes - condensation, precipitation, infiltration, runoff, and evapotranspiration- make up the Hydrologic Cycle.
Answer:
5 processes involved in water cycle are .
condensation precipitationinfiltrationrunoffevapotranspirationhope it is helpful to you ☺️
There is an estimated 10-100 trillion bacteria and other microorganisms living in the human digestive system, forming a mutualistic relationship in which all species benefit. Recently, much research has been done on the role of these microorganisms in the development of disease, the brain, and behavior.
Drag the terms on the left to the appropriate blanks on the right to complete the sentences. Not all terms will be used.
The________ is a layer of cells lining the blood vessels within the brain, acting as a filter that controls the molecules that pass between the blood and the brain.
An organism's ________ is the collection of all the microorganisms (e.g. bacteria, phages, fungi) that live inside the digestive system of that individual.
A_______is a type of intercellular protein connection between animal cells that prevents leakage of materials through the space between the cells.
The transmembrane protein ________ is one of the component proteins of a tight junction.
________lack all microorganisms in their digestive systems, a state achieved by delivering them through cesarean section and raising them in sterile incubators.
_______ are raised under sterile conditions to limit their exposure disease-causing microorganisms.
tight junction
gut microbiota gap junction
germ-free mice pathogen-free mice
blood brain barrier adhesion plaque
occludin
Answer:
- The blood brain barrier is a layer of cells lining the blood vessels within the brain, acting as a filter that controls the molecules that pass between the blood and the brain.
- An organism's gut microbiota is the collection of all the microorganisms (e.g. bacteria, phages, fungi) that live inside the digestive system of that individual.
- A gap junction is a type of intercellular protein connection between animal cells that prevents leakage of materials through the space between the cells.
- The transmembrane protein occludin is one of the component proteins of a tight junction.
- Germ-free mice lack all microorganisms in their digestive systems, a state achieved by delivering them through cesarean section and raising them in sterile incubators.
- Pathogen-free mice are raised under sterile conditions to limit their exposure disease-causing microorganisms.
Explanation:
The blood-brain barrier is a layer of cells made up of endothelial cells that act to limit the passage of substances from the bloodstream in a more selective manner than endothelial cells of capillaries located in other parts of the body. Gut microbiota can be defined as all the microorganisms (i.e., bacteria) inhabiting the mammalian gastrointestinal tract, which helps to ferment non-digestible substrates (e.g., dietary fibers). A gap junction is a class of cell junction that is formed between cells contacting each other which allows small molecules (e.g., water, ions, metabolites, microRNA sequences, etc) to pass through this intercellular communication. In vertebrate animals, cell junctions can be divided into 1-gap junctions (communication between cells), 2-tight junctions (occludin junctions), and 3-adherens junctions, hemidesmosomes and desmosomes (anchor junctions). Tight Junctions are composed of multiple proteins including transmembrane proteins such as occludin, tricellulin, junctional adhesion molecule (JAM), and one member of the claudin protein family. Germfree animals are research animals that have no microorganisms living in or on them, which are housed in controlled/isolated conditions to prevent any type of contamination. Finally, pathogen-free animals are research animals that are guaranteed to be free of particular pathogenic (harmful) microorganisms.
In the food web above, if new species of insect were introduced that fed primarily on plantains, how would the following populations be affected? Indicate your answer by increase , decrease or no change and include a brief explanation of your reasoning.
A) greenfly
B) rabbit
C) fox
Answer:
This is a 50/50 answer. I believe it would be fox, sorry if this is incorrect.
Answer:
Greenfly- no change
The greenfly would remain unaffected because it doesn’t rely on plantains.
Rabbit- decrease
The rabbit relies on plantains as food so more competition would result in a decrease in the rabbit population
Fox- decrease
Lesser food means lesser foxes. The foxes prey like the rabbit and mouse eat plantains. If the mouse and fat population goes down so would the fox population.
What are altitudes? help pls
Answer:
Altitude is how high vertically something is by definition
1 : height above a certain level and especially above sea level. 2 : the perpendicular distance from the base of a geometric figure to the vertex or to the side parallel to the base.
What are the forms of potential energy that can be used by a cell
Answer:
Adenosine triphosphate
Does the number of cell layers or the cell shape play a role in the function of the epithelial tissue
Which statement about scientific notation is true?
O A. It provides a way of measurement without units.
B. It allows scientists to make calculations more easily.
C. It allows scientists to invent new units of measurement.
D. It is a system of mathematical symbols used to describe energy
and matter.
Why do v sneeze
plz explain it step by step
Clear-cutting and logging of tropical rain forests causes issues with excess carbon dioxide in the atmosphere and low rainfall. The land that is cleared and used for farming become depleted of nutrients and thus are useless. Do we have any right to tell other countries how to manage their lands, such as rain forests? If we explain the consequences of clear-cutting the rain forests but that government decides to continue with the process, should we interfere?
Answer:
yes cause those tropical rain forests are important
Explanation:
How does increased biodiversity increase the stability of a community?
A. High biodiversity increases the chances that a community will
encounter an extreme disturbance.
B. High biodiversity decreases the chances that a community will be
able to survive a disturbance.
C. High biodiversity increases the chances that a community will be
able to survive a disturbance.
D. High biodiversity decreases the chances that a community will
encounter an extreme disturbance.
Answer:
B
Explanation:
High biodiversity decreases the chances that a community will be
able to survive a disturbance.
High biodiversity decreases the chances that a community will be able to survive a disturbance. Therefore option " B" is correct.
What is biodiversity?Biodiversity is a word used when all the different varieties of life forms, therefore, animals, microorganisms, and plants all come together and work. both biotic and abiotic factors are included in biodiversity. There can be a variety of species that co-exist altogether.
There are three levels of biodiversity species diversity, ecosystem diversity, and genetic diversity. Examples are pine trees, sunflowers, blue whales, tigers, and all types of microorganisms. The threats to biodiversity are an invasion of alien species and an increase in the number of predators.
Therefore, biodiversity is all species coexisting altogether.
Learn more about biodiversity, here:
https://brainly.com/question/23101752
#SPJ7
functions of the female reproductive organs
define the following terms
Nutrition
Autotrophic
What is biotechnology, and what are some examples from the ocean?
Answer:
Marine biotechnology may include techniques such as bioprocessing, bioharvesting, bioprospecting, bioremediation, using bioreactors etc (so called process biotechnology techniques); aquaculture/fisheries; gene, protein, or other molecule based techniques; while applications may include: health, food, cosmetics
Part C: Take Notes In a separate location, take notes from the sources you have identified. The notes will provide details for your presentation. While taking notes from texts and websites, use these reading strategies. In the space provided, write four pieces of information that you intend to use in your presentation. im to lazy to write the notes
Answer:
I do that sometimes I take notes in a separate location so is this like for your math homework cuz I am good enough but I don't like it that much but I'm good at it and sources identify things that will the source is like a key a key like you can open and close the door with and you're opening the key with the source so it really really really really and wouldn't be a good thing to take notes wherever you go like if you were writing a book you would want the source and the emotion and everything you wanted to buy
Use the drop-down menu to complete the
sentence.
are capable of differentiation to
form specialized cells.
DONE
Answer:
The correct answer is - stem cells.
Explanation:
Stem cells can give rise to all tissues and organs in the body. These cells can differentiate into any form of cells, which allows them to repair tissues that have been damaged by various physiological or natural ways
There are two types of stem cells: Adult Stem Cells and Embryonic stem cells.
Cells that are present in the bone marrow or umbilical cord of a newborn baby and can be divided as Hematopoietic, a cell that can form blood cells and the immune system, and mesenchymal that form the body's cartilage, bones, muscles and other.
Embryonic stem cells are found on at blastocyst stage of embryo. These cells can transform into any type of tissue in the human body, which increases their treatment potential.
Answer:
stem cells
Explanation:
Because I'm smart...
ECOSYSTEM
Organelle x
Gas A + H2O
Organic molecule Gas B
Organelle Y
Mantenerey
Answer:
i dont know what work this is it looks hard
Explanation:
but sorry icant help
Increasing __________ is one of the most effective treatments for bowel and bladder problems.
What did you remember to include in your paragraph?
As a general rule, should sample turbidity corresponds to sample fluorescence in liquid E.coli cultures?
Answer:
Throughout the explanation segment, the description of the query is presented below.
Explanation:
The turbidity spectrometer depending on the intensity isn't a trustworthy indication of microbial cell numbers. However, these should still be utilized as parameter estimates instead of the exact numbers.Benefits at all from the measurement of the radiation reflected by both acutely and chronically organisms, since adsorption capacities change as a result of the current microbiological composition.Primary sensory afferent axons have widely varying diameters, and their size correlates with the type of receptor to which they are attached. Write down the axons that are the smallest and the slowest?
Answer:
Smaller and slower axons are those related to temperature, itching and pain.
Explanation:
As you may already know, the axon is an extension of the neuron that has the ability to transmit signals to cells, indicating the nerve impulse that must be felt by the body. In other words, the axons receive a synapse, which is the nerve impulse, and pass this message on to a nerve cell to turn it into a sensation. These axons have varying diameters and the speed at which they transmit messages also varies. According to researches, the smaller and slower axons are those related to the sensation of temperature, itching and pain.
species specific category
Answer:
cool cool cool cool cool cool
What family does rat belong to
Answer:
Rat. The laboratory rat, Rattus norvegicus, belongs to the order Rodentia and family Muridae. Rats were first used for experimental purposes in the mid 1800s. Strains were developed to study neuroanatomy, nutrition, endocrinology, genetics and behavior.
Explanation:
hope this helps you
give 4 examples of metabolic reactions
What are some of the benefits of roundworms? Check all that apply.
They help purify sources of fresh water.
They feed on pests like termites, fleas, and ants.
They can be used to treat patients with blood clots.
They break down organic matter in the soil.
They aid in nutrient cycling.
Answer:
B) They feed on pests like termites, fleas, and ants.
D) They break down organic matter in the soil.
E) They aid in nutrient cycling.
Explanation:
It's on Edge 2020
Answer:
✔️They feed on pests like termites, fleas, and ants.
✔️ They break down organic matter in the soil.
✔️ They aid in nutrient cycling.
Explanation:
Time4Learning
How many kingdoms are there in the domain Bacteria?
O A2
OB. 1
O c. 3
O D. 4
Answer:
There is 1 kingdom in the domain Bacteria
Explanation:
Answer:
B. 1
Explanation:
one Kingdom
Domain Bacteria has one Kingdom: Kingdom Eubacteria.
How many kingdoms are there in the domain bacteria? | Study ...https://study.com › academy › answer › how-many-kingd...
First 20 elements which are isotopes?
Answer:
Isotopes (Stable) of the elements
Text lists sorted by:Value | Atomic Number | Alphabetical
Plots:Shaded | Ball | Crossed Line | Scatter | Sorted ScatterLog scale plots:Shaded | Ball | Crossed Line | Scatter | Sorted ScatterGood for this property:Atomic Number
Hydrogen1H, 2HHelium3He, 4HeLithium6Li, 7LiBeryllium9BeBoron10B, 11BCarbon12C, 13CNitrogen14N, 15NOxygen16O, 17O, 18OFluorine19FNeon20Ne, 21Ne, 22NeSodium23NaMagnesium24Mg, 25Mg, 26MgAluminum27AlSilicon28Si, 29Si, 30SiPhosphorus31PSulfur32S, 33S, 34S, 36SChlorine35Cl, 37ClArgon36Ar, 38Ar, 40ArPotassium39K, 41KCalcium40Ca, 42Ca, 43Ca, 44Ca, 46CaScandium45ScTitanium46Ti, 47Ti, 48Ti, 49Ti, 50TiVanadium51VChromium50Cr, 52Cr, 53Cr, 54CrManganese55MnIron54Fe, 56Fe, 57Fe, 58FeCobalt59CoNickel58Ni, 60Ni, 61Ni, 62Ni, 64NiCopper63Cu, 65CuZinc64Zn, 66Zn, 67Zn, 68Zn, 70ZnGallium69Ga, 71GaGermanium70Ge, 72Ge, 73Ge, 74GeArsenic75AsSelenium74Se, 76Se, 77Se, 78Se, 80SeBromine79Br, 81BrKrypton78Kr, 80Kr, 82Kr, 83Kr, 84Kr, 86KrRubidium85RbStrontium84Sr, 86Sr, 87Sr, 88SrYttrium89YZirconium90Zr, 91Zr, 92Zr, 94ZrNiobium93NbMolybdenum92Mo, 94Mo, 95Mo, 96Mo, 97Mo, 98MoTechnetiumNoneRuthenium100Ru, 101Ru, 102Ru, 104Ru, 96Ru, 98Ru, 99RuRhodium103RhPalladium102Pd, 104Pd, 105Pd, 106Pd, 108Pd, 110PdSilver107Ag, 109AgCadmium106Cd, 108Cd, 110Cd, 111Cd, 112Cd, 114CdIndium113InTin112Sn, 114Sn, 115Sn, 116Sn, 117Sn, 118Sn, 119Sn, 120Sn, 122Sn, 124SnAntimony121Sb, 123SbTellurium120Te, 122Te, 124Te, 125Te, 126TeIodine127IXenon124Xe, 126Xe, 128Xe, 129Xe, 130Xe, 131Xe, 132Xe, 134Xe, 136XeCesium133CsBarium130Ba, 132Ba, 134Ba, 135Ba, 136Ba, 137Ba, 138BaLanthanum139LaCerium136Ce, 138Ce, 140Ce, 142CePraseodymium141PrNeodymium142Nd, 143Nd, 145Nd, 146Nd, 148NdPromethiumNoneSamarium144Sm, 149Sm, 150Sm, 152Sm, 154SmEuropium151Eu, 153EuGadolinium154Gd, 155Gd, 156Gd, 157Gd, 158Gd, 160GdTerbium159TbDysprosium156Dy, 158Dy, 160Dy, 161Dy, 162Dy, 163Dy, 164DyHolmium165HoErbium162Er, 164Er, 166Er, 167Er, 168Er, 170ErThulium169TmYtterbium168Yb, 170Yb, 171Yb, 172Yb, 173Yb, 174Yb, 176YbLutetium175LuHafnium176Hf, 177Hf, 178Hf, 179Hf, 180HfTantalum181TaTungsten180W, 182W, 183W, 184W, 186WRhenium185ReOsmium184Os, 187Os, 188Os, 189Os, 190Os, 192OsIridium191Ir, 193IrPlatinum192Pt, 194Pt, 195Pt, 196Pt, 198PtGold197AuMercury196Hg, 198Hg, 199Hg, 200Hg, 201Hg, 202Hg, 204HgThallium203Tl, 205TlLead204Pb, 206Pb, 207Pb, 208PbBismuthNonePoloniumNoneAstatineNoneRadonNoneFranciumNoneRadiumNoneActiniumNoneThorium232ThProtactiniumNoneUraniumNoneNeptuniumNonePlutoniumNoneAmericiumNoneCuriumNoneBerkeliumNoneCaliforniumNoneEinsteiniumNoneFermiumNoneMendeleviumNoneNobeliumNoneLawrenciumNoneRutherfordiumNoneDubniumNoneSeaborgiumNoneBohriumNoneHassiumNoneMeitneriumNoneDarmstadtiumNoneRoentgeniumNoneCoperniciumNoneNihoniumNoneFleroviumNoneMoscoviumNoneLivermoriumNoneTennessineNoneOganessonNone
Answer:
I know 5 though
Oxygen 16O,17O,18O
fluorine 19F
hydrogen 1H,2H
neon 20Ne,21Ne,22Ne
sodium 23Na
I hope I have helped you babes ❤️
40 points! Help pls im super confused and need to get this right to pass
Answer:
Layer A deposited, Layer B deposited, Layer C deposited, Layer faulting
Explanation:
All layers would match up if not for the fault. This means that each layer was laid down at the same time and the faulting occurred afterwards.