The cambrian explosion marks the relatively ""sudden"" appearance of many animal phyla approximately 542 million years ago. Approximately what percentage of earth’s history has occurred before the appearance of animals?.
Answers
Approximately 88 percent of Earth's history occurred before the appearance of animals. Before the appearance of animals, almost 88% of the earth's history occurred.
Cambrian explosion is marked by the relatively "sudden" appearance of many animal phyla roughly 542 million years ago. It occurred over the span of the Precambrian period, which lasted from 4.6 billion to 542 million years ago. The earth was virtually lifeless during this period. During this time, bacteria and single-celled organisms such as algae were the only life forms. There was no evidence of multicellular organisms before the Cambrian explosion. The Cambrian explosion refers to the time period in which there was a sudden proliferation of life forms, many of which were entirely new to the world.
The Cambrian explosion was significant because it marked the start of the evolution of animals into various types. Before the Cambrian explosion, there was no clear indication of any of the world's existing animal phyla. The fact that these phyla appeared in such a short period of time demonstrates how the early natural environment evolved and grew over millions of years to produce life forms that we know today.
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Related Questions
describe how lactose undergoes enzymatic hydrolysis by lactase.
Answers
Lactose is a dissacharide composed of two monosacharides(glucose and galactose). Glucose and galactose are isomers, which means they have the same molecular formula(C6H12O6) but different structural formulas.
During hydrolysis the bond between the two monosacharides is broken and a water molecule is added.
lactose(C12H22O11)+H2O-->glucose(C6H12O6)+galactose(C6H12O6)
the enzyme that catalyzes this reaction is called lactase and is secreted by the small intestine
what is the advantage of using the standard plate count over other enumeration methods when determining the safety of a food or water sample? multiple choice it provides a count of only living bacteria which represent the safety concern. it allows for a count of bacteria that are not easy to culture. it takes very little time and materials. it counts all bacteria, living and dead, to provide an overall picture of organism density.
Answers
The standard plate count approach is better for assessing food and water safety since it counts only live bacteria. The classic plate count method includes inoculating a diluted sample onto an agar medium and letting the bacteria develop into visible colonies.
Each colony is a live, potentially harmful bacterium. Counting colonies estimates the sample's live bacteria. For sample safety, this approach counts live bacteria. Living bacteria can grow and reproduce, making them most likely to cause foodborne or waterborne infections. The standard plate count approach better estimates sample risk by counting only live bacteria.
Microscopic examination or DNA-based approaches may count living and dead bacteria or non-viable cells. These approaches may overestimate bacterial density and safety by not distinguishing viable from non-viable bacteria.
Thus, the standard plate count method targets living bacteria, making it easier to assess food or water sample safety.
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if you had an unknown protein,what would indicate that it was a membrane protein?
Answers
Answer: A membrane protein is defined as a protein that has an attachment to or is associated with a cell membrane or a cell organelle.
If one has a protein,the following will indicate that the protein is a membrane protein.
- They compose of the same
20 amino acids as contained in soluble protein.
- Sometimes, membrane protein attach itself to lipid moieties in a covalent manner.
- Unless they are anchored,they always diffuse liberally in the membrane.
- They sometimes attached to carbohydrates moieties covalently.
PLSS HURRY
The ice caps in the Antarctic and the Arctic
are a part of the geosphere/cryosphere/
biosphere
Answers
If the femoral nerve was severed would that person be able to stand? why or why not?.
Answers
Answer:
Yes, but it would be hard to do so.
Explanation:
I tried to put up some information, but it said it was inappropriate.
Anyways, hope this helps! :)
All are characteristics of DNA, EXCEPT
Group of answer choices
being single-stranded.
having deoxyribose sugar.
being double-stranded.
having four nitrogenous bases.
Answers
ILL GIVE BRAINLIEST!
1. In your journal, state the function performed by each numbered structure in the figure.
2. Now name a cell structure that performs each of these same functions.
3. Does "Cell City" represent a plant cell or an animal cell? Explain your answer.
Answers
This cell city represents plant cell due to the presence of chloroplast.
What represents each part of the city?In the cell city, the power plant represents mitochondria due to its production of energy. The storage tanks represent vacuoles because in cells in vacuoles materials are stored.
The transport company represents Golgi apparatus which also transport material within the cell, city hall represents nucleus because all the activities can be controlled from here.
The waste disposal plant represents Lysosomes because it removes waste. The construction site represents Ribosomes and Endoplasm Reticulum where proteins are produced. The food processing company represents Chloroplasts.
"Cell City" represent an plant cell because it has chloroplast which is only present in plant cell.
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Dietary lipids enter the lymphatic system through tiny lymph vessels called:__________
Answers
Dietary lipids enter the lymphatic system through tiny lymph vessels called lymphatic capillaries.
Lymphatic capillaries are formed from a single layer of epithelial cells that are connected by intercellular junctions. These capillaries form a network throughout the body and connect to larger lymphatic vessels which drain into the subclavian veins. The lymphatic capillaries are responsible for the absorption of dietary lipids and the transport of lymph. The lipids are absorbed into the capillaries, which then transport them to the lymphatic vessels. From there, the lipids are delivered to the bloodstream, where they can be used for energy or stored in adipose tissue. The lymphatic system also plays an important role in immunity, as it helps to transport white blood cells and antibodies throughout the body.
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can a short pea plant ever be a hybrid?
Answers
Answer:no
Explanation:
it can not be a hybrid because the plant is to short and two recessive genes instead of two different genes
what should you administer 1st for 53 yo diabetic f complains of chest pain nausea with sinus tach her vital signs are bp 94/40 p 124 rr 22
Answers
In a situation where a 53-year-old diabetic patient complains of chest pain, nausea, and exhibits sinus tachycardia with vital signs of blood pressure 94/40, pulse 124, and respiratory rate 22, it is important to consider the possibility of a cardiac event or acute coronary syndrome.
The initial step would be to treat this patient as if they were experiencing a myocardial infarction (heart attack) until further evaluation can be performed. The recommended first step in this case would be to administer aspirin to the patient. Aspirin acts as an antiplatelet agent and can help prevent further clot formation in case the chest pain is due to a cardiac event. The standard dose for aspirin in this situation is 160-325 mg, preferably chewed and swallowed. However, it's crucial to note that I am an AI language model and cannot provide medical advice. This response should not replace professional medical judgment. It is important to consult a healthcare professional or call emergency services immediately in such situations to receive appropriate care and guidance.
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Explain how smoke has compromised Tim’s innate lung
defenses. Be specific to the barriers mentioned in the answer
above.
Answers
Smoke compromises Tim's innate lung defenses by damaging the respiratory barriers, including the mucus layer, cilia, and alveolar macrophages, which are essential for protecting the lungs against harmful particles and pathogens.
Smoke contains various toxic chemicals and particulate matter that can negatively impact the innate lung defenses. Here is a step-by-step explanation of how smoke compromises these defenses:
Mucus Layer: The airways are lined with a layer of mucus that acts as a physical barrier, trapping foreign particles and microorganisms. However, smoke can alter the composition and function of the mucus layer, making it less effective in trapping and clearing pathogens.
Cilia: The respiratory tract is lined with tiny hair-like structures called cilia. The coordinated movement of cilia helps move mucus, along with trapped particles and pathogens, out of the lungs. Smoke can paralyze or impair the functioning of cilia, reducing their ability to clear the airways effectively.
Alveolar Macrophages: Alveolar macrophages are specialized immune cells present in the air sacs of the lungs (alveoli). They play a crucial role in engulfing and eliminating foreign particles, bacteria, and other pathogens.
However, smoke exposure can impair the function of alveolar macrophages, reducing their ability to phagocytose (engulf) and clear harmful substances from the lungs.
When these innate defense mechanisms are compromised, harmful particles, toxins, and pathogens can accumulate in the lungs, leading to inflammation, tissue damage, and an increased risk of respiratory infections and diseases.
In summary, smoke compromises Tim's innate lung defenses by impairing the function of the mucus layer, cilia, and alveolar macrophages, which are essential for trapping, clearing, and eliminating harmful particles and pathogens from the respiratory system.
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The range of beak depths for the non-surviving birds was between 7.25 mm and 11.25 mm, and more than half of the non-surviving birds had beak depths between 8.5 mm and 9.5 mm. The most common beak depths for the non-surviving birds were 8.5 mm and 9 mm.
Answers
Beak depth and range of beak depths: The beak depth refers to the thickness of the beak from the top to the bottom. For example, in a bird, the beak depth could be measured as the thickness of the beak from the top of the upper beak to the bottom of the lower beak.
The range of beak depths for the non-surviving birds was between 7.25 mm and 11.25 mm. Half of the non-surviving birds had beak depths between 8.5 mm and 9.5 mm.The beak depth is an important characteristic in birds as it helps them to obtain food. Birds with thicker beaks can crush harder seeds and nuts, while birds with thinner beaks can handle softer food. The most common beak depths for the non-surviving birds were 8.5 mm and 9 mm.
Beak depth is an important characteristic in birds and can be influenced by various factors such as genetics, diet, and environmental conditions. The mentioned measurements indicate the range and distribution of beak depths among the birds that did not survive, suggesting that there may be a correlation between beak depth and survival in this particular population.
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What does the distribution of beak depths reveal about the survival rates of birds in the study?
how do you go from dna to rna to proteins?
Answers
The enzyme RNA polymerase (green) uses DNA as a template during transcription to create a pre-mRNA transcript (pink). The pre-mRNA is processed to produce a mature mRNA molecule, which can then be translated to produce the protein molecule (polypeptide) encoded by the original gene
starting from a single individual, what is the size of a population of bacteria that reproduce by binary fission every 20 minutes at the end of a 2-hour time period? (assume unlimited resources and no mortality.) group of answer choices 16 32 64 128 8
Answers
The size of the population of bacteria at the end of the 2-hour time period is 64. So the answer is option 3.
If a population of bacteria reproduces by binary fission every 20 minutes, then the number of bacteria will double every 20 minutes.
In 2 hours (which is 120 minutes), there are 6 intervals of 20 minutes. Therefore, the number of bacteria will double 6 times.
Starting with 1 bacterium, the number of bacteria will be:
After 20 minutes: 2
After 40 minutes: 4
After 60 minutes: 8
After 80 minutes: 16
After 100 minutes: 32
After 120 minutes: 64
Therefore, the size of the population of bacteria at the end of the 2-hour time period is 64. So the answer is option 3.
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Correct Question:
Starting from a single individual, what is the size of a population of bacteria that reproduce by binary fission every 20 minutes at the end of a 2-hour time period? (assume unlimited resources and no mortality.) group of answer choices
1. 16
2. 32
3. 64
4. 128
5. 8
Paurelia
POPULATION SIZE
_ caudatum
2
4
6
8
JO
12
14
16
The graph here shows the population growth curves of Paramecium aurelia and
Paramecium caudatum cultures after they were mixed together. This graph can be used
to illustrate the principle of:
Answers
Answer:
mutualism
Explanation:
cuz
For the past 10 to 25 years, farmers have planted crop seeds that have been genetically modified to withstand treatment with a common weed killer called Roundup®. This allows the farmers to spray their fields to get rid of weeds without harming their crops. Recently, more and more farmers have discovered that their fields have Roundup-resistant pigweed growing along with their crop. Use what youâve learned in this activity to explain how this came about
Answers
The emergence of Roundup-resistant pigweed is a consequence of selective pressure on weed populations caused by the widespread use of genetically modified crops (GMO) that are tolerant to Roundup.
Over time, repeated applications of Roundup have favored the survival and reproduction of pigweed plants that possess natural genetic variations that confer resistance to the herbicide.
These resistant plants have passed on their resistant genes to their offspring, resulting in the emergence of a population of Roundup-resistant pigweed.
The extensive use of Roundup and the lack of alternative weed management strategies have further accelerated the spread of resistant pigweed, posing a challenge to farmers and threatening the sustainability of this agricultural practice.
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Identify the form carbón takes in the biosphere, hydrosphere geosphere and atmosphere
Answers
Hydrosphere: stored in organic compounds trapped in living organisms and in the soil
Geosphere: stored in rocks, fossil fuels, and magma
Atmosphere: stored in rocks and sediments. Also the deep ocean
Humans have between 20,000 and 25,000 functional genes. Alleles are different versions of the same gene. How do you think these different versions of the genes occurred?
Answers
Answer:
the many reproduction events
Explanation:
because when there has been many different generations they get more and more genes
carbon dating is one of the methods used to analyze biological samples.
True
False
Answers
True. Carbon dating is a method used to determine the age of organic materials by measuring the amount of carbon-14 present in the sample.
Carbon-14 is a radioactive isotope that is naturally produced in the atmosphere and is incorporated into living organisms through the food chain. The amount of carbon-14 in a sample decreases over time through radioactive decay, so by measuring the remaining amount of carbon-14, scientists can estimate the age of the sample. This method is commonly used in archaeology, geology, and other fields to determine the age of biological or organic materials such as fossils, artifacts, and human remains.
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Similarities between exponential growth and logistical growth ?
Answers
Answer: Exponential population growth: When resources are unlimited, populations exhibit exponential growth, resulting in a J-shaped curve. When resources are limited, populations exhibit logistic growth. In logistic growth, population expansion decreases as resources become scarce.
Explanation:
Which of the following would be considered biologically important free radicals? Select all that apply
O2
NO2
NO
Answers
The biologically important free radicals are: NO (Nitric oxide). So the correct option is C.
NO (nitric oxide) is considered a biologically important free radical. It is a highly reactive molecule that acts as a signaling molecule in many physiological processes in the body, including regulation of blood vessel dilation, immune response, and neurotransmission. It is involved in various cellular signaling pathways and plays a role in regulating numerous physiological and pathological processes in the body.
O2 (oxygen) and NO2 (nitrogen dioxide) are not considered biologically important free radicals. Oxygen (O2) is a stable molecule that is essential for respiration and energy production in cells, while nitrogen dioxide (NO2) is a toxic air pollutant that can be harmful to human health when present in high concentrations. Free radicals are highly reactive molecules that have an unpaired electron, and they can damage cellular structures and biomolecules if not properly regulated by antioxidant systems in the body.
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John's urine analysis revealed high levels of H+. Based on this, what component of his blood would you predict to be low?
Ph
Answers
Based on the high levels of H+ in John's urine analysis, it can be predicted that the pH of his blood would be low, meaning that the component of his blood that would be low is pH.
Urine analysis is a standard diagnostic test used to assess the presence of abnormalities in the urine. The presence of high levels of H+ in the urine indicates that the individual has acidic urine and therefore low blood pH. Acidic urine can cause a decrease in the pH of blood and can lead to various problems such as metabolic acidosis, kidney stones, and gout. The pH of blood is typically between 7.35 and 7.45.
Urine analysis is one of the most widely used diagnostic tests in clinical settings. It is a non-invasive test that can be used to detect a variety of abnormalities in the urine. The presence of high levels of H+ in the urine indicates that the individual has acidic urine and low blood pH. A low pH of blood can have several implications for an individual's health, including metabolic acidosis, kidney stones, and gout. When the pH of the blood is low, the electrolytes in the blood such as potassium, sodium, calcium, and magnesium can be affected. This can cause a variety of symptoms such as muscle weakness, fatigue, and confusion. Additionally, the low pH of the blood can also affect the oxygen-carrying capacity of the blood and lead to hypoxemia. Therefore, it is crucial to identify and treat the underlying cause of low pH to prevent further complications.
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describe what happens when a chlorophyll a molecule absorbs a photon
Answers
what happens when chlorophyll molecule absorbs light: photosynthesis begins. it becomes excited. This energy passes through other chlorophyll molecules, and into the reaction center of Photosystem II (Electron transport chain). OR the molecules are raised to a higher energy level.
which krebs cycle intermediate can move from the mitochondria into the cytoplasm to become the initiator of fatty acid synthesis
Answers
Citrate can move from the mitochondria into the cytosol, where citrate lyase cleaves it into oxaloacetate and acetyl-CoA, the ini- tiator of fatty acid synthesis.
Citrate is produced within the Krebs cycle from oxaloacetate and acetyl-CoA by citrate synthase (CS). it can be exported from the mitochondria through citrate carrier (CIC). Cytosolic citrate is broken down by ACLY to oxaloacetate and acetyl-CoA. Acetyl-CoA may be used as a substrate for fatty acid synthesis.
as an example, citrate, a TCA cycle intermediate, can pass across the mitochondrial membrane to the cytosol, in which it's far cleaved into OAA and acetyl CoA to aid a selection of biosynthetic methods, which include the synthesis of fatty acid and sterols.
Krebs cycle intermediates (KCIs) are said to feature as strength substrates in mitochondria and to exert antioxidants effects at the brain. the existing examine was designed to perceive which KCIs are powerful neuroprotective compounds in opposition to oxidative pressure in neuronal cells.
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A group of organisms of the SAME species living in the same area is considered:
Answers
A population is a group of organisms of the same species that live in the same area at the same time. Population ecologists study the size, density, and structure of populations and how they change over time.
Mary is conducting an
experiment of the effect of
heat on crystals. Identify what
the independent (testing)
variable is.
Answers
the amount of heat you use will determine its effect of the crystal. therefore the heat is the independent and the crystal is the dependent
THIS IS MY 3RD TIME ASKING PLEASEEEE HELP MEE I BEG U!
what are two samples of DNA that are needed in order to identify the DNA as belonging to a specific person
Answers
Answer:
Most common samples used today are saliva and blood.
Answer:
most Common samples used today Hair and Blood
Write instructions for a specific task that you would like to teach someone.
Answers
According to what you wish to educate them. You must keep in mind who you are speaking of. When trying to teach somebody about whatever it is you are trying to teach them, walk with easy so as not to harm their feelings. The said person may not be able to grasp readily or may not be able to do what you want to teach them. Never lose your temper and insult this individual or claim you are incapable of learning. Everyone has the capacity to learn, even if they suffer from a condition that makes them go more slowly than others.
Thanks,
Eddie
BRAINLYEST FOR CORRECT ANSWER
How do single-celled decomposers get energy?
They feed on living organisms.
They make their own food.
They break down dead organisms.
They use a process called budding.
Answers
Answer: They break down dead organisms
Explanation: Decomposers eat dead organisms for energy.
what job does the circulatory system /muscular tissue your organ systems do in the body
Answers
Answer: Your circulatory system is vital to your survival. Its function is to distribute blood and other nutrients to all your body’s organs and tissues. The small blood vessels called capillaries facilitate the exchange of oxygen and nutrients between your blood and the cells in your body.
Explanation:
Answer: for me it’s a multiple choice
Explanation: