Answer:
=IF(i9 ≥ 40, "YES" , "NO" )
Explanation:
Here, IF is the condition
we know that,
IF ( logical_test , [value_if_true] , [value_if_false] )
Here we are using greater than formula :
=IF(i9 ≥ 40, "YES" , "NO" )
It means that,
If the package is more than or equal to 40 then it will show "yes", or otherwise "no"
Here we are using yes instead of true and no instead of false
Which of the following applies to a viral infection?Viral infections Viruses can be treated with antibiotics.Viruses can only replicate with in a cell or living tissue.Viruses are larger than bacteria.Viruses are made of cells.
Viruses can only replicate within a living cell or tissue and cannot be treated with antibiotics. Vaccines are a preventive measure against viral infections. Antiviral drugs are limited and disease-specific.
Among the options provided about a viral infection, the correct statement is that viruses can only replicate within a cell or living tissue. Viruses are obligate intracellular parasites, meaning they require the machinery of living cells to produce more viruses. Antibiotics are ineffective against viruses, as they are designed to target the structures and processes of bacteria, which are different from virions. While some antiviral medications exist, they are limited in number and are disease-specific.
Vaccines, on the other hand, are a proactive measure to prevent viral infections by triggering the immune system to recognize and combat the virus upon exposure. Understanding these details about viral replication and treatment is essential, as viruses cause numerous diseases such as the common cold, influenza, and AIDS, among others.
The boxer crab, Lybia tesselata, carries a small pair of anemones in its claws. When approached by a predator, it waves the anemones around, presenting the stinging tentacles and chasing away the predator. The anemones benefit by eating food particles from prey that the crab catches. What type of relationship is this?
Explanation:
Mutualism is most normally characterized such that mirrors the positive signs describing the result of their cooperations, that is, as connections between people of various species that advantage them two. However, mutualism can be all the more unequivocally characterized as a cooperation between people of various species that outcomes in constructive (useful) consequences for per capita proliferation or potentially endurance of the interfacing populaces. As in other interspecific cooperations, the level of reliance of every mutualist upon different reaches from commit to facultative; henceforth, they can be commit, commit facultative, or facultative–facultative communications.Answer:
Mutualism.
Explanation:
Edmentum.
The phosphorus cycle differs from the carbon cycle in that: A. there is little or no human impact on the phosphorus cycle. B. phosphorus is not a critical component of living organisms. C. plants play a role in the carbon cycle, but have no role in the phosphorus cycle. D. the atmosphere does not contribute to the phosphorus cycle. E. the hydrosphere plays a role in the phosphorus cycle.
Answer: D. the atmosphere does not contribute to the phosphorus cycle.
Explanation:
The phosphorus cycle is different as compared to the carbon, water and nitrogen cycle as the phosphorus element cannot be found in the gaseous state as a result of this the phosphorus cannot be found in the earth atmosphere. The phosphorus can be found in the sedimentary mineral rocks. The weathering process of the sedimentary mineral rocks provides the inorganic phosphorus to the plants. This way the phosphorus cycle begins with the food chain.
Carbon in the form of carbon dioxide, carbon monoxide and other gases can be found in the atmosphere.
The phosphorus cycle differs from the carbon cycle in that the atmosphere does not contribute to the phosphorus cycle, which is not the case with the carbon cycle.
Explanation:The phosphorus cycle differs from the carbon cycle mainly in that the phosphorus cycle does not include a significant atmospheric component. While plants and human activities impact both cycles, the key distinction for the phosphorus cycle is that the atmosphere does not contribute to it, unlike the carbon cycle where the atmosphere plays a major role through processes like photosynthesis and respiration.
Phosphorus is an essential nutrient in living processes, being a crucial part of nucleic acids and phospholipids, and as calcium phosphate, it is a component of our bones. Phosphorus is often the limiting nutrient for growth in aquatic ecosystems, highlighting its importance.
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The relative location of four genes on a chromosome can be mapped from the following data on crossover frequencies Genes B and D Frequency of Crossover 5% Cand A 15% A and B 30% C and B 45% Cand D 50% Which of the following represents the relative positions of these four genes on the chromosome? 1. ABCD 2. ADCB 3. CABD 4. CBAD
Answer:
The relative position of the genes on the chromosome is CABD
Explanation:
According to the observed recombination events, C and D are the furthest from each other, while C is closest to A, being therefore CABD the correct gene order in the chromosome
A plant absorbs 200 J/g of energy from the sun. A cow eats the plant and absorbs 20 J/g of energy. The cow is fed to a group of humans who absorb 2 J/g from the meat. What is the main reason the energy consumption decreases from one consumption to the next? A) Some energy is wasted as heat. B) The humans use some energy chewing. C) The plant uses the energy to make sugar. D) The cow uses some energy to make proteins.
Explanation:
Energy is moved between life forms through the food in a nourishment jaw. Evolved way of life starts with makers. They make food utilizing sun oriented energy. They are eaten by essential customers which are thus eaten by optional buyers, etc. A lot of energy are lost from the biological system when vitality is moved starting with one living beings then onto the next. 90% of the energy available at each step in the food chain is lost as heatHence, the right answer is option "A" Some energy is wasted as heat"Answer:
A. Some energy is wasted as heat.
Explanation:
Because transferring energy requires heat.
Which of the following is the earliest step in transcription? A. RNA polymerase encounters a termination signal, and the DNA molecule is released. B. Complementary RNA nucleotides are synthesized and added to the mRNA molecule. C. Introns are excised from the pre-mRNA strand. D. RNA polymerase binds to the promoter on the template strand of DNA.
Answer:
D. RNA polymerase binds to the promoter on the template strand of DNA.
Explanation:
Transcription is the process in which mRNA is formed from the DNA molecules. DNA is a double-stranded molecule but only one strand is used to code the RNA molecule and the strand which is used to code RNA is called the template strand.
RNA polymerase binds on the promoter regions which is present on the template strand and starts transcribing the strand. The complementary sequence is added to make the RNA strand. Therefore the correct answer is D.
Which of the following is true regarding LDL: Select one: a. Diets lower in simple carbohydrate and saturated fats, along with regular physical activity, can reduce LDL-cholesterol. b. LDL can adhere to the walls of the blood vessels, contributing to the development of atherosclerosis c. The more LDL-cholesterol circulating in the blood the greater the risk of cardiovascular disease d. All of the above
Answer: D. All of the above
Explanation: Low-density lipoprotein is one of the five major groups of lipoprotein which transport all fat molecules around the body, it can be called bad cholesterol. High level of Low density lipoprotein can lead to diverse health issues such as it increases the risk of cardiovascular diseases, it accumulates in the walls of blood vessels causing the blood vessel to be hard and thick leading to a disease called Atherosclerosis. However, physical exercise and a food with low or no cholesterol will help reduce the intake of Low density lipoproteins.
If you were called away during the electrophoresis procedure and were not able to monitor your electrophoresis run, what do you think would happen if the electricity were to remain running in your absence
Answer:
During the process of gel electrophoresis, the DNA separates on the basis of charge to mass ration and forms bands as it moves towards the positive end of the gel.
If the electricity is kept running for too long, then the DNA will continue to run in the positive direction and might exit the far end of the gel. As a result, there will be no band formation due to which the experiment will become incorrect.
Leaving an electrophoresis run unattended could result in an overheated gel, damaged DNA fragments, evaporated buffer solution, and potential risk of fire or equipment damage due to prolonged unsupervised operation.
Explanation:If an electrophoresis procedure was left running unattended with the electricity on, several outcomes could occur. The most immediate risk is that the gel could overheat and possibly melt or distort, depending on the duration and intensity of the current. This overheating could damage the DNA fragments in the gel, making them difficult or impossible to analyze. Furthermore, if left running for too long, the buffer solution within the electrophoresis chamber could evaporate, leading to an increased risk of fire as well as compromised results due to the altered conductivity of the buffer. Eventually, the power source or electrophoresis apparatus could be damaged due to continuous operation without supervision.
When sperm and egg cells undergo meiosis, the number of chromosomes goes from ______ to _______. When an egg is fertilized by a sperm cell that number goes from ______ to ______.
Answer:
2n to n, n to 2n
Explanation:
Meiosis is known as reductional division because in meiosis the chromosome number gets reduced to half in daughter cells so when sperm and egg cells undergo meiosis than the chromosome numbers get reduced from 2n to n. In humans, the chromosome number is 46 and it gets reduced to 23 after meiosis.
When egg is fertilized by the sperm than the two chromosomes comes in the same cell and the number goes from n to 2n that mean in human it goes from 23 to 46.
In the case when the sperm and egg cells undergo meiosis, so here the chromosomes should be 2 to 1. And, when the egg should be fertilized so the number should be 1 to 2.
What is Meiosis?
It refers to the reduction in the division that leads in the creation of the 4 haploid daughter cells via the diploid parent. It should be restricted for the s-ex cells in se-xually reproducing organism. So at the time when the sperm and eggs cells so the number should be 2 to 1. And, at the time when haploid egg should be fertilized by a haploid sperm so it create zygote i.e. diploid.
Therefore, it should be 2 to 1 and 1 to 2.
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What major changes to farming made it difficult for average farmers to compete with large agricultural corporations during the 1920s? Group of answer choices Chemical fertilizers increased yield. Hybrid seeds increased yield. Mechanization increased efficiency. All of the above.
Answer:
The answer includes all of the options.
Explanation:
Some of the major changes that happened in agriculture during the 1920s include the use of electrical tools and vehicles and chemical fertilizers. These changes along with their low availability to the average farmers made it harder for them to compete with agricultural corporations who could use these advanced methods easily. Hybrid seeds were also used by corporations to get increase the yield of the fields. The answer includes all of the options.
I hope this answer helps.
Drag each tile to the correct box. Nina studies an artificial heart model. The model has tubes that supply an electric current to the model. Nina switches on the current that provides an impulse to the heart. She observes that the heart contracts and relaxes. Compare this model with that of a human heart, and place the steps describing how blood flows through the human heart in order.
Answer:
The correct order is:
Electrical signal travels toward the heart .Signal received by the nodes in the atrium .The atria contract .Signal received by the atrioventricular node.Signal transferred to the ventricles .The ventricles contract .Explanation:
The steps are:
Signal transferred to the ventricles .The atria contract .Electrical signal travels toward the heart .The ventricles contract .Signal received by the nodes in the atrium .Signal received by the atrioventricular node.The question refers to the heart's physiological electrical conduction mechanism, which goes from the atrial node to the atrioventricular node, passes to the bundle of His and its branches, and then extends through the Purkinje fiber system, all so that coordinated events occur that allow blood flow within this organ.
The correct order of steps, linked to the activity of the heart and blood flow are:
Electrical signal travels towards the heart: the autonomic nervous system conducts the nerve impulse to the heart. Signal received by the nodes in the atrium: the atrial node, a structure that is located on the right atrium, receives the nerve impulse and is responsible for transmitting it to the ventricular atrial node. The atria contract: the contraction of this structure drives the blood to the ventricles, promoting the simultaneous opening of the atrioventricular valves. Signal received by the atrioventricular node: a node located in the interventricular septum is responsible for the distribution of the impulse to the His-Purkinje system. Signal transferred to the ventricles: the nerve signal passes to the His bundle, its branches and then the Purkinje fibers found in both ventricles. The ventricles contract: ventricular contraction promotes the emptying of your cavities, passing blood from the right ventricle to the lungs, and from the left ventricle to the general circulation. At this time the atrioventricular valves are closed and the sigmoid valves are opened, to allow anterograde blood flow.Learn more:
Movement of oxygenated blood leaving the heart https://brainly.com/question/2375870
Answer:
1. electrical signal travels toward the heart
2. signal by the nodes in the atrium
3. the atria contract
4. signal received by the atrioventricular node
5. signal transferred to the ventricles
6. the ventricles contract
Explanation:
Inexhaustible resources are renewable energy sources that are found in unlimited amounts in nature. Water is an example of an inexhaustible resource. Humans can impact the amount and quality of the water. Which description is not how developing countries are affecting water as an inexhaustible resource?
Explanation:
Many developing countries are implementing renewable energy sourcesSolid air, sunny skies, plentiful plant matter, heat from the earth, and quick-moving water can each give a tremendous and continually renewed stockpile of vitality. A moderately little division of US power right now originates from these sources, however, that could change: examines have over and again indicated that sustainable power source can give a noteworthy portion of future power needs, much in the wake of representing potential imperativesRenewable sources of energy are those which can be used again and again and they do not get extinct after usageFor example – solar energy, wind energy, geothermal energy, etc. The use of renewable energy sources depicts that the country is well aware of the harms caused by the usage of non-renewable energy resources. Therefore instead of using water (considering it as an inexhaustible resource), the developing countries are exploring other renewable sources of energyAnswer:
d
Explanation:
Suppose you dissolve 1 gram of solid glucose crystals in 1 kg of water to make a solution. Which calculation would be best to describe the concentration of glucose?
Answer:
"mass/mass percent" calculation to express the concentration of glucose.
Explanation:
Concentration of the solution is generally a ratio between the amount of solute and the amount of solvent (or solution). In this case, the amount of solute is measured in grams, and the amount of solvent (water) is measured in kilograms. Both units are units of mass. It would be most likely to use by mass/mass percent.
Answer: The calculation that would make the most sense to use in this scenario is mass/mass percent.
Explanation: For anyone who's taking the quiz
In a neuron, an action potential travels from the soma to the last structure of the neuron called the ________. The signal is received from the next neuron through its ________.
An action potential travels from the soma to the axon terminal of a neuron. The signal is then received by the next neuron through its dendrites.
Explanation:In a neuron, an action potential travels from the soma (or cell body) to the last structure of the neuron called the axon terminal. This is where the electrical signal that travels down the neuron is converted into a chemical signal. The signal is received from the subsequent neuron through its dendrites. This is a process called synaptic transmission and is fundamental to the communication between neurons in the nervous system.
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In a neuron, an action potential travels from the soma to the axon terminal. The signal is then received by the next neuron through its dendrites.
Explanation:In a neuron, an action potential travels from the soma, or the cell body, towards the last structure of the neuron, known as the axon terminal. The signal is then received by the next neuron through its dendrites. Dendrites serve as input sites where signals are received from other neurons. The signal then passes through the soma and is taken up by the axon. The axon is a tube-like structure which carries this signal or action potential down to the axon terminals. The axon terminals consist of synaptic vesicles that contain neurotransmitters. These neurotransmitters are the chemical messengers of the nervous system that allow signals to be communicated to other neurons, muscle cells, or target organs. Thus, the process of signal transfer in the nervous system continues.
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Scar tissue is the result of ________.A) an abnormally large number of collagen fibers and relatively few blood vessels at the repair site.B) increased numbers of epidermal layers in the area of the injury.C) a thickened stratum germinativum in the area of the injury.D) increased numbers of fibroblasts and mast cells in the injured area.E) a lack of hair follicles and sebaceous glands in the injured area.
Answer: A) an abnormally large number of collagen fibers and relatively few blood vessels at the repair site
Explanation:
The scar tissues are the thick fibrous tissues typically the collagen fiber that have the role of replacement of healthy tissues after the injury has taken place to initiate the recovery process.
The scars are produced as a biological process at the site of wound repair on the skin. The scar develops on the superficial surface of the skin due to external injury. It is a natural healing process.
There are few blood vessels that can be found at the site of repair along with the collagen fibers.
You are designing an artificial drug-delivery cell that can penetrate animal cells. Which protist structures should provide the most likely avenue for research along these lines?
Explanation:
A group of cytoskeletal structures and related layer limited organelles found at the foremost finish of grown-up commit intracellular protozoan parasites in the phylum Apicomplexa. The apical complex is engaged with connection to and infiltration of the host cell and in parasite multiplication. Apicomplexans : Ciliates are pretty cool, but they're not the only group of alveolates out there. Next, we've got the apicomplexans. This group is characterized by an asymmetrical collection of alveoli at one end of the cell, which is called the apical complex. the apical complex has shaped the way it is because it helps the cell latch onto and infects other cells.That's right, apicomplexans are parasitic. There are 4,000 known species of apicomplexans, all of them parasitic, and some of them pretty nasty.Which of the following would not be a basis for misrepresentation? a. These shrubs will survive in direct sunlight. b. This lawnmower has a safety turn-off switch. c. This soft water system will add five years to the life of your washing machine. d. All of the above are a basis for misrepresentation.
Answer:
i believe your answer is d.
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FSH, LH, and TSH all have a similar structure and are found in vertebrates and invertebrates alike. Therefore, they can be defined as _____
a. synonymous
b. adverse
c. identical
d. analogous
e. homologous
Answer:
FSH, LH, and TSH all have a similar structure and are found in vertebrates and invertebrates alike. Therefore, they can be defined as HOMOLOGOUS
Explanation:
FSH, LH, and TSH are homologous because of similarities in their structure which are found across both vertebrate and invertebrate
Two members of the excavate clade that can cause disease are:______. a. euglenids and kinetoplastids. b. dinoflagellates and apicomplexans. c. loboseans and plasmodial slime molds. d. cercozoans and foraminiferans. e. diplomonads and parabasalids.
Answer:
E. diplomonads and parabasalids.
One example of a cellular response to a signal is the triggering of cell division. If a mutation occurred in the gene for the signal receptor in this pathway that caused the receptor to reject binding of the signal, what response can be predicted?
Answer:
Automatically, the cell does not divide.
__________ is your ability to integrate eye, hand, and foot movements into cohesive action. When it comes time to execute a maneuver, this makes it happen smoothly.
Answer:
The answer is Coordination
In examining a protist, you notice that it lacks a cell wall, and has movement with cytoplasmic streaming. These data allow you to infer that the species belongs to which of the following protist groups? In examining a protist, you notice that it lacks a cell wall, and has movement with cytoplasmic streaming. These data allow you to infer that the species belongs to which of the following protist groups? A) Rhizaria B) Stramenopila C) Alveolata D) Excavata E) Amoebozoa
Answer:
E. Amoebozoa
Explanation:
Amoebozoa is ranked as a phylum within either the kingdom Protista or the kingdom Protozoa. They lack cell wall with cytoplasmic streaming and possesses false projections used for locomotion.
The protist in question, characterized by the lack of a cell wall and movement through cytoplasmic streaming, is most likely a member of the Amoebozoa group.
Explanation:In examining a protist that lacks a cell wall and shows movement through cytoplasmic streaming, you can determine that the species likely belongs to the Amoebozoa group. The defining characteristics of pseudopodia exhibiting cytoplasmic streaming for movement and nutrient distribution, as seen in Amoebozoans, match the observations described. While Rhizaria also utilizes pseudopodia, the absence of cell walls is more characteristic of Amoebozoa, which includes many free-living and parasitic species known for this feature.
Which phylum has members that secrete a hard, calcium carbonate shell?
- Arthropoda
- Nematoda
- Cnidaria
- Mollusca
Answer:
i believe your answer would be Mollusca.
Explanation:
(i looked it up on britannica if you have any questions.) Mollusk, also spelled mollusc, any soft-bodied invertebrate of the phylum Mollusca, usually wholly or partly enclosed in a calcium carbonate shell secreted by a soft mantle covering the body.
Fill in the blanks.1. The specific location within an enzyme molecule where the substrate binds is called the:_______ . 2. During an enzymatic reaction, a molecule of binds to the enzyme and is broken down into one or more molecules of , __________which are released. 3. A_____________ is a molecule that can bind to an enzyme and prevent the enzyme from working. 4. Lactose takes years to break down on its own. But if exposed to the protein lactase, the reaction proceeds very quickly, while lactase itself remains unchanged. Lactase is an example of a_____________ . 5. The___________ between an active site and its substrate often strains bonds and helps the reaction proceed.
Answer:
Active siteProductsInhibitor Enzyme Enzyme-susbtrtae complexExplanation:
1. Active site: The active site is the region of an enzyme where the substrate gets attached undergo a chemical reaction.
2. Products: Products are the molecules which formed at the end of enzymatic reaction.
3. Inhibitor: A chemical molecule other than enzyme that binds to the active site and prevents enzymatic reaction.
4. Enzyme: It is a biocatalyst which speed up chemical reaction.
5. Enzyme-substrate complex: A short-lived complex formed when substrate binds to the active site of enzyme.
This response explains key terms related to enzyme reactions, including the active site, substrates, products, competitive inhibitors, catalysts, and the interaction between an active site and substrate.
Explanation:1. The specific location within an enzyme molecule where the substrate binds is called the active site.
2. During an enzymatic reaction, a molecule of substrate binds to the enzyme and is broken down into one or more molecules of product, which are released.
3. A competitive inhibitor is a molecule that can bind to an enzyme and prevent the enzyme from working.
4. Lactase is an example of a catalyst.
5. The interaction between an active site and its substrate often strains bonds and helps the reaction proceed.
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Which of the following is a protein produced by cells when exposed to a virus. This
protein binds to the cell membranes of neighboring cells and "interferes" with the
ability of a virus to enter the cell.
A. interferon
B. prion
C. vaccine
D. bacteriophage
Answer: Interferon - a protein produced by cells when exposed to a virus. This protein binds to the cell membranes of neighboring cells and "interferes" with the ability of a virus to enter the cell.
Explanation: Hope this helps have a great day! please mark brainliest!
Interferon is the protein produced by virus-exposed cells, signaling neighboring cells to defend against viral infection by inhibiting virus entry and promoting the destruction of the virus. It plays a crucial role in the immune system's fight against viral infections.
The protein produced by cells when exposed to a virus, which binds to the cell membranes of neighboring cells and "interferes" with the ability of a virus to enter the cell, is interferon. Interferons are types of cytokines released by a cell that has been infected with a virus. They play a critical role in the immune response by signaling uninfected neighboring cells to inhibit mRNA synthesis, destroy RNA, and reduce protein synthesis, as well as promoting apoptosis in cells infected with the virus. This action helps in preventing the spread of the virus, protecting uninfected cells from becoming infected.
Interferons stimulate antiviral responses in nearby cells as well as in the cells secreting them, although they do not cure the cells releasing them. The significant antiviral effects of interferons include inhibition of viral mRNA synthesis, destruction of viral RNA, reduction of protein synthesis, and promoting the apoptosis (programmed cell death) of infected cells. This collective action effectively stems the infection from further spreading.
The gene for the MyoD transcription factor is introduced into cultured fat cells. When the gene is expressed, the fat cells are transformed into muscle cells. What does this result imply about the fat cells and their commitment to the fat-cell fate?
Answer:
The result implies that fat cells are committed to this fate, but not irreversibly determined.
Explanation:
The expression of Myod is capable of converting a fibroblast to a skeletal muscle cell. Due to the fact that it can do this, it is therefore a model system in developmental biology for studying how a single initiating event can orchestrate a highly complex and predictable response. Recent findings indicate that Myod functions in an instructive chromatin context and it regulates muscle cell differentiation by inducing cell cycle arrest, a prerequisite for myogenic initiation. The protein is also involved in muscle regeneration. It activates its own transcription which may stabilize commitment to myogenesis.
Acid-fast organisms such as Mycobacterium tuberculosis resist decolorization by an acid-alcohol wash because of the high concentration of __________ in their cell walls.
Answer:
Acid -fast organisms resist decolonization by an acid alcohol wash because of high concentration of lipid in their cell wall.
Explanation:
Acid fast organisms contain a wax like impermeable cell wall which contain mycolic acid and large amount of fatty acid,waxes and complex lipid.Acid fast organisms are highly resistant to disinfectants and dry condition Mycobacteria possess thick waxy cell wall rich in mycolic acid. This makes it difficult to be stained using Gram's techniques. But with the use of carbon fuschen,the cell wall can be stained using acid-fast technique.
Acid-fast organisms resist decolorization by an acid-alcohol wash due to the high concentration of mycolic acids in their cell walls. These long chain, branched fatty acids contribute to the complexity and waxy nature of the cell wall.
Explanation:Acid-fast organisms like Mycobacterium tuberculosis resist the effects of acid-alcohol wash due to their high concentration of mycolic acid in their cell walls. These mycolic acids are long chain, branched fatty acids which contribute to the cell wall's complexity and waxy nature. As a result, acid-fast organisms are resistant to decolorization and even some sterilization and disinfection procedures, making them more challenging to treat.
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Natural selection cannot make an elephant run as fast as a cheetah and fly like a bird. This is an example of: Group of answer choices 1. disequilibrium. 2. genetic drift. 3. physical constraints on natural selection. 4. a correlated response to selection.
Final answer:
Natural selection is limited by existing genetic variation and cannot create new traits from scratch.
Explanation:
Natural selection is a driving force in evolution, but it is limited by the existing genetic variation in a population. It can only act on the variation that already exists and cannot create new traits from scratch. So, natural selection cannot make an elephant run as fast as a cheetah or fly like a bird due to the physical constraints on natural selection.
Additionally, the source of new genetic variation primarily arises from processes like mutation and recombination, which occur randomly.
Why are sponges considered to be an evolutionary dead end
Answer:Sponges are often considered an evolutionary dead end because they are so specialized in pumping water through their bodies that it is considered impossible to be modified into anything else. Although sessile, sponges can change their shape and grow towards water rich food.
Explanation: please give brainliest!
Sponges are considered an evolutionary dead end due to their lack of specialized cell types for more complex bodies and reliance on diffusion and osmosis, leading to a simple cellular structure that has remained largely unchanged over time.
Why Sponges Are Considered an Evolutionary Dead End:
Sponges, belonging to the phylum Porifera, are often considered an evolutionary dead end because they lack the specialized cell types necessary for developing more complex body plans. Sponges rely on diffusion and osmosis for physiological processes such as gas exchange, circulation, and excretion, which necessitates a design that increases their surface area to volume ratio. This is one reason why sponges have maintained a relatively simple body structure over hundreds of millions of years without evolving into more complex organisms.
Moreover, sponges embody a cell-level organization, as opposed to the tissue-level organization found in most other animals. Each sponge cell performs specific jobs, which limits their collective ability to form more complex systems and organs that could conduct sophisticated functions. Therefore, while sponges are successful organisms adapted to their niches, their simple cellular architecture has prevented them from evolving into more advanced forms, making them appear as an evolutionary dead end in the lineage of multicellular animals.
It is worth noting, however, that sponges still exhibit a variety of feeding strategies. Most are filter-feeders, but some host photosynthesizing micro-organisms as endosymbionts, and there are even species of carnivorous sponges that prey on small crustaceans.
The anadromous stickleback fish that made their was from the ocean to the lake had what type of protection from predators in the ocean?
A. Lots of spikes
B. They had full armored plates along their sides
C. Only A
D. Both A and B
Explanation:
D. Both A and B
The anandromous stickleback fish has a protective armour in the form of lots of spikes and full armoured side plates. Whenever chased by a predator it spreads its plates and spine . As a result , the predator could not swallow it or tears its jaw injuring itself.