Answer:
Sodium ion
Explanation:
A sodium/potassium ion channel protein would help the muscle cells counteract this tendency by pumping potassium (K+) into the cell and sodium (Na+) out. This raises the concentration of K+ ions within the axoplasm relative to the outside causing the Na+ ions to diffuse out. This is the resting potential
A scientific variable is something that Select in an experiment.
Select
changes
moves
remains
Answer:
A scientific variable is one that make changes in the experiment.
Explanation:
The things that are changing in an scientific experiment is called variables. Variables are something can make changes or effect the result of study. Variables are needed for every study in order to understand the differences. A variable is a condition or a factor that exist in different types or amount. There are three types of variable in a scientific experiment. Independent variable, dependent variable, and control variable. Independent variable is one that changes may occur and it is observed. Dependent variable is one that scientist should focus on observation to know how it respond to the changes on the independent variable.Control variable are quantities that should remain constant.Which of the following describes how livestock can impact water quality?
Water withdrawals add stress in areas with low supply.
Waste can seep into groundwater supplies.
Pesticides, insecticides, and other chemicals can poison aquatic animals.
Soil particles or sediments can run off into water supplies and cloud water.
Answer: D
Explanation:
D is the answer
Answer:
The correct answer is the last statement.
Explanation:
Overgrazing by livestock results in soil erosion, which eventually causes sediments to run-off and get transported into an adjacent water body. This results in water turbidity. Overgrazing removes the grasses, thus, exposing the top cover soil to water erosion and wind.
The withdrawal of the ground cover can also enhance drying, thus damaging the organic matter, and hampering the soil composition, which makes soil erosion to occur easily. Thus, overgrazing can hamper the composition of the soil, diminishing infiltration, and enhancing run-off.
Look at this diagram of a plant.
Which label points to the feature of angiosperms that holds the developed seeds?
W
X
Y
Z
Answer:
W- developed seeds
X-angiosperm
Explanation:
Well for one, these two are the only things w/ a referrable image (I'm not sure if that's a word :-)) Another thing is angiosperm literally means flowering plant and a tomato is a ripe, or flowering, plant. W is an image of seeds that are at mid stage in there developing process, so it is clearly the answer. Correct me if im wrong :-D.
When the sun reaches the end of
released into space, forming a
life cycle, the expanded part will be
O
A. red giant
O
B. brown dwarf
c. white dwarf
O
O
D. planetary nebula
When the sun reaches the end of released into space, forming a life cycle, the expanded part will be Planetary nebula.
Explanation:
Planetary nebula formed after when the external layer is shredded due to running out of fuel so that it can burn. This external layer of gas expand into the space, the shape of nebula can often be ring shaped or even a bubble. At the centre of this nebula it has the shinning left over middle part of the star. This star can also be seen. The temperature of the nebula is 100000C. The planetary nebula last for about 10000 years between its formation and the recombination.
How are the number of chromosomes maintained during asexual reproduction?
Answer:
The number of chromosomes is maintained through the process of mitosis during asexual reproduction.
Mitosis can be described as a process in which a cell divides and produces two daughter cells which are exactly similar to the parent cell. The chromosome number of the daughter cells will be the same as the parent cells. No crossing over or recombination occurs during this type of cell division. Hence, mitosis is an effective way to maintain the chromosome number of organisms which reproduce asexually.
The no of chromosomes of a organism of each generation is maintained due to the meiosis.
Explanation:
The meosis is a kind of reductive division for the higher organisms and for the higher organism it is mitosis. The mitosis is the phase where the organism reproduce asexually, in this phase the two resulting daughter cells always contains the same no of chromosomes as the parent cell from which they derive.
The role of chromosomes is to maintain the each cell division is constant. It help us to enable us to grow and self maintenance of the body.
Which statement best describes the difference between the sympathetic and parasympathetic nervous systems?
A.
The sympathetic system sends signals within the brain and the parasympathetic system sends signals between the brain and the body.
B.
The sympathetic system contains the brain and spinal cord and the parasympathetic system contains the peripheral nerves.
C.
The sympathetic system controls voluntary body movements and the parasympathetic system controls involuntary functions.
D.
The sympathetic system prepares the body for stress and activity and the parasympathetic system prepares the body for rest.
Answer:
D. The sympathetic system prepares the body for stress and activity and the parasympathetic system prepares the body for rest.
Explanation:
Sympathetic and Parasympathetic nervous system are two divisions of autonomic nervous system.Acetylcholine is a common neurotransmitter released by preganglionic neurons of both systems.The post Ganglionic neurons of these two systems release different neurotransmitter.The sympathetic nervous system is concerned with 'fight and flight response'The parasympathetic nervous system is concerned with 'rest and digest ' response.18. If a cell needs to get waste out and nutrients in, this works best if
we reduce ______
and increase _____
Answer:
We reduce the size of the cell
and increase surface area to volume ratio.
Explanation:
All cells contain cell membranes. Which of the following describes the composition of cell membranes?
A. Cell membranes are composed of carbohydrate chains, which allow all materials to enter and leave the cell.
B. Cell membranes are composed of cellulose, which provides rigidity for the cell.
C. Cell membranes are composed of cytoplasm, which allows proteins to be excreted by the cell.
D. Cell membranes are composed of lipid molecules, which provide a flexible structure.
The cell membrane is selectively permeable, are composed of lipid molecules, which provide a flexible structure. Thus option D is correct.
What is cell membrane?The cell membrane is a thin selectively semi-permeable membrane present in all living organism including bacteria, plant and animals, it is an outer covering of a cell by surrounding cell cytoplasm.
The two major components are Proteins and lipids where as the ratio of protein to lipid may vary depending on types of cells, most common type of lipid in membrane are phospholipid, which form a semi-permeable lipid bilayer.
This lipid are amphipathic in nature means it has hydrophilic or water loving head and hydrophobic or water hating tail group, which help them to interact with both polar and nonpolar solvent respectively.
Some organelles like nucleus and mitochondria have double layered cell membrane, cell membrane provide protection to cell and maintain the integrity of the internal environment and act as a communication agent.
Thus option D is correct.
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Final answer:
Cell membranes are composed of lipid molecules, which provide a flexible structure. They also contain proteins and cholesterol.
Explanation:
The composition of cell membranes is primarily made up of lipid molecules, which provide a flexible structure. These lipids form a phospholipid bilayer with hydrophobic tails facing inward and hydrophilic heads facing outward. Additionally, cell membranes also contain various proteins and cholesterol that are embedded within the lipid bilayer.
help me with this plllllssss
Answer:
The correct option is D. The Linnaean System showed relationship between organisms based on observable characteristics.
Explanation:
Carolus Linnaeus is known as the father of taxonomy. Two main important contributions by Carlous Linnaeus were:
Classification based on hierarchyBinomial nomenclatureLinneaus Classification divided organisms into
KingdomClass.OrderGenusSpeciesThe method of binomial nomenclature uses the technique of naming organisms based on the genus and species name. This name is known as scientific name and it provides a unique name to each organism.
What kind of bonding occurs between carbon atoms, allowing carbon to form stable molecules?
Single, double, and triple covalent bonds
Single, double, and triple ionic bonds
Single, double, and triple hydrogen bonds
Single, double, and triple metallic bonds
Answer:
The correct answer is single,double and triple covalent bonds .
Explanation:
A carbon atom can form a single bond with another carbon atom example ethane.
A carbon atom can form a double bond with another carbon atom example ethylene
A carbon atom can form a triple bond with another carbon atom example acetylene.
But during the formation of Carbon carbon single bond or double bond or triple bond the valency of carbon atom that is 4 is always maintained.
review the setup for photosynthesis select all primary limiting factors that impact the rate of photosynthesis for this lab setup
Answer:
The limiting factors are oxygen concentration, carbon dioxide concentration and light intensity
Explanation:
All the factors have to be in efficient amounts for photosynthesis to take place. If one is inefficient, the process will be affected; just like a three legged stool, if you remove one leg, the chair won't be able to stand.
Answer:
Option A, B and C are correct
Explanation:
The major limiting factors for this experimental setup would be –
1) Light intensity – Photosynthesis can occur even at a low intensity light but to achieve the maximum efficiency and output the intensity of light must be high. This is the reason why plants photosynthesize the maximum during the brightest time of the day.
2) Concentration of carbon dioxide – Higher the concentration of carbon dioxide, higher is the rate of photosynthesis. Plants take carbon dioxide from the atmosphere.
3) Oxygen – The oxygen concentration must be favorable for photosynthesis up to its optimum level. Beyond the optimum oxygen level, the photosynthesis process inhibits.
Which of the following statements is true?
Electrons have a negative charge.
The n=1 shell can hold eight electrons.
The number of electrons in an atom is equal to the number of neutrons.
The second electron shell can hold 16 electrons.
Explanation:
"Electrons have a negative charge." This is true. Electrons are found on the outside of the nucleus of an atom possessing a negative charge. "The n=1 shell can hold eight electrons." This is false. The n=1 can hold 2 electrons. "The number of electrons in an atom is equal to the number of neutrons." This is false. The number of electrons in a (neutral) atom is equal to the number of protons, not neutrons. "The second electron shell can hold 16 electrons." This is false. the number of electrons the electron shell can hold is 8 electrons.example of omnivores
An omnivore eats both plants and animals!
Badgers, pandas, raccoons, and dogs are examples of omnivores I think!
Answer: human, raccoons, opossums, pigs, rats, badgers, and most bear species
Explanation:
The sequence of dna from your snork is found in which organelle?
Explanation:
The nucleus is a large membrane-bound organelle that houses the genetic information, DNA, in the cell.
Sequences of DNA make up genes which can have different forms called alleles. DNA is transcribed into mRNA and later translated into amino acids which are linked together by rRNA to form proteins.
Further Explanation:
All the genetic information within the eukaryotic cell is stored within the nucleus as helical DNA. This DNA is tightly wound around histones as chromosomes. Chromosomes within the nucleus is unwound, unzipped and read by enzymes in a complex series of steps known as transcription. The message on DNA, called genes is copied by RNA polymerase, to form mRNA complementary sequence to that of the DNA strand. These are then translated into proteins in ribosomes.
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10 ml of a 3% hydrogen peroxide solution is added to five test tubes. As the hydrogen peroxide decomposes to produce oxygen gas, the rate of oxygen production is rated on a scale of 0 - 5, 0 meaning "no oxygen" and 5 meaning "fast".
Potential Catalyst Effects On Reaction Rate
Reactant -----Oxygen produced
H2O2------ 2
+0.1M FeCl3------ 5
+0.1M NaCl------- 0
+0.1M Fe(NO3)2----- 4
+0.1M KNO3---- 0
To the other four test tubes of hydrogen peroxide, five drops of additional solutions are added. The solutions are indicated in the data table as well as the rate of oxygen production for each.
Based on the data, what is the MOST appropriate conclusion for this experiment?
A) Iron compounds are always used as catalysts.
B) Reaction rate is always increased by iron compounds.
C) Increasing the temperature increases the rate of decomposition.
D) Iron compounds are a catalyst for the decomposition of hydrogen peroxide.
Answer:
D) Iron compounds are a catalyst for the decomposition of hydrogen peroxide.
Explanation:
The reaction of descomposition of hydrogen peroxide (H₂O₂) to produce oxygen (O₂) is:
2H₂O₂ → 2H₂O + O₂
Based on the data of potential catalys effects on reaction rate:
A) Iron compounds are always used as catalysts. FALSE. It is possible to know that, for this reaction, iron compounds are acting as catalyst but there is no information about all reactions to know that iron compounds are always catalysy
B) Reaction rate is always increased by iron compounds. FALSE. Again, for this reaction iron compounds increases reaction rate but it is not possible to know that reaction rate is always increased by iron compounds.
C) Increasing the temperature increases the rate of decomposition. FALSE. There is no information about temperature of reaction.
D) Iron compounds are a catalyst for the decomposition of hydrogen peroxide. TRUE. As both iron compounds increases the rate of reaction, it is possible to say that iron compounds are a catalyst for the descomposition of hydrogen peroxide.
I hope it helps!
Answer:
D
Explanation:
According to the experimental data, iron compounds are a catalyst for the decomposition of hydrogen peroxide. Both test tubes with H2O2 plus Fe(III) compounds show an increase in oxygen production, which in turn indicates an increase in the rate of reaction. There is no temperature variable in this experiment.
Which of the following tags should be used to retrieve information from a
database about a DNA segment of a human gene that codes for a specific
protein?
A. Nucleotide sequence, human, hemoglobin
B. Sugar monomer, amino acid, fatty acid
O
C. Mouse, chromosome II, centrosome
O
D. Human, mouse, fruit fly
SUBMIT
Answer:
The correct option is A. Nucleotide sequence, human, hemoglobin
Explanation:
If the segment of the DNA for the human gene is known then it will be very easy to find the gene on a database. The tags which should be used will be the nucleotide sequence, where the known sequence shall be mentioned.
Then we will choose the tag for the organism which is humans in this case. Then we will select the tag for the protein which is made by the nucleotide sequence, which is protein in this case. Hence, option A is the correct answer.
Which biome is characterized by plants that drop their leaves in the winter? A. desert B. tropical rainforest C. taiga D. deciduous forest
Answer:
D. deciduous forest.
Explanation:
This biome is named for the dominant trees that drop their leaves during the winter months.
Can you please answer these 5 questions ? :)
1. Explain how changes in energy flow and chemical cycles can affect ecosystems
2.How can a disturbance is a key feature of a community?
3. Chthamalus example and overlapping niches
4. What are the similarities and differences between energy and chemicals
5.What is the relationship between latitude and species richness?
Pleaseee and thank you
Answer:
1. Changes in energy flow and chemical cycle can affect the productivity of the ecosystem.
2. Disturbance is a key feature of the community because it is the disturbance that produces diversity within the community.
3. A niche is the combination of an organism’s habitat, its adaptations and its role in the habitat. In the absence of competition from other species an organism can occupy its range and it is called fundamental niche. Due to competition its niche narrows and the narrowed down niche is called realized niche.
4. In its niche Chthamalus, a type of barnacle has to face competition from Balanus which is also a barnacle. Thus the realized niche of Chthamalus is the high tide zone. In the absence of competition from Balanus whole of the inter-tidal zone is the niche of Chthamalus which is its fundamental niche.
5. Species richness decreases on moving from lower latitudes to higher latitudes. Species richness is more near the equator and on moving towards the poles it decreases.
Glucokinase and hexokinase catalyze the first glycolysis reaction; glucokinase has a higher Km. Which is true? A. hexokinase is always functional and is not regulated by negative feedback B. they are not isozymes C. glucokinase is not a zymogen D. glucokinase becomes active from high levels of fructose
Answer:
The correct answer is C glucokinase is not a zymogen
Explanation:
zymogens are secreted as inactive enzyme which undergo activation by autocatalysis which deals with the removal of short peptide fragment from that zymogen resulting in the formation of active enzyme.
Foe example chymotrypsin enzyme is secreted as zymogens but not glucokinase.
15 points plez help. Explain why an area that goes through secondary succession will likely reach its climax community before an area that goes through primary succession.
Answer:
Primary succession can be described as the development of a community in an area where there was no form of life before. For example, an area where volcanic eruption might have occurred.
Secondary succession can be described as an ecological succession which occurs in areas where the previous community had been destroyed by some kind of environmental disaster or human activity like fire etc.
As secondary succession occurs in areas where there was life before that means that the soil of this area will still have essential minerals and nutrients which will support life better as compared to areas of primary succession. In primary succession, the area might not even have soil. The rocks will be converted to soil in these area which will take a lot of time. Hence, an area that goes through secondary succession will likely reach its climax community before an area that goes through primary succession.
Answer:
The answer that they gave was
"An area going through secondary succession reaches its climax community faster because the area begins with some soil and some plant and animal species. An area that goes through primary succession, on the other hand, begins with no soil and no organisms, so reaching the climax community takes longer."
Explanation:
explain and give an example of and organism that can have 2 symbiosis relationships
Answer:
lichens
mycorrhiza
Explanation:
Lichens are formed by two types of organisms- an alga and fungus. The mycelium of the fungus forms athin mat which offers anchorage and protection to some microscopic algae. The alga provides the fungus with sugars which it produces through photosynthesis.
Mycorrhiza is a type of symbiotic relationship between a saprophytic fungus and vascular plants such as coniferous trees. The fungus develops in the soil near the base of the tree. Some of the hyphae penetrate into the outer layers into the soil from which it obtains mineral ions. It also decomposes proteins to their amino acids. The fungus shares these nutrients with its tree host.
describe how the results of the hershey-chase experiment would have been different if proteins were the genetic material
 Imagine a change in the iguana's habitat from dry land to aquatic. Based on the Generation I allelic frequencies, we can assume only a small percentage of iguanas had webbed feet and were able to survive. Over many generations, if their habitat remains aquatic, iguanas without webbed feet will disappear from this population.
Predict what should happen to the allelic frequencies within the iguana population over time.
A)A new species of iguana will evolve.B)The dominant and recessive alleles will eventually balance out.C)The dominant allele will eventually disappear from the gene pool.D)The recessive allele will begin to mask the effects of the dominant allele.
Submit

Hint
Evolution
(SB6.d) Genetic Changes And Populations
Answer:
The correct option is C. The dominant allele will eventually disappear from the gene pool.
Explanation:
According to the theory of natural selection, only those organisms are able to survive and reproduce which are better adapted to survive the environmental changes. A trait that is not required by the organisms of a species will become extinct whether it be a dominant trait of a recessive trait. Hence, in the above scenario, the dominant trait will eventually disappear as it no longer has any function to the changed environmental conditions.
Final answer:
In a population of iguanas that undergoes a habitat change from dry land to aquatic, the allelic frequencies will change over time. Specifically, the alleles for webbed feet (which allow iguanas to survive in the new aquatic habitat) will increase in frequency, while the alleles for non-webbed feet will decrease and may eventually disappear. This is an example of natural selection.
Explanation:
In a population of iguanas that undergoes a habitat change from dry land to aquatic, the allelic frequencies will change over time. Specifically, the alleles for webbed feet (which allow iguanas to survive in the new aquatic habitat) will increase in frequency, while the alleles for non-webbed feet will decrease and may eventually disappear. This process is an example of natural selection, where individuals with advantageous traits have a greater chance of surviving and reproducing.
Therefore, the correct prediction for the allelic frequencies within the iguana population over time is option C) The dominant allele will eventually disappear from the gene pool.
can you please tell me the answer
5 hours
Explanation:
Because it will
In the organization of living things, a __ would include the largest number of individuals
Answer:
The correct option is B) ecosystem
Explanation:
Species can be described as a group or organisms that can interbreed and produce fertile offsprings.
A population can be described as the number of a particular type of species which are living in a given area at a particular time and they have the ability to breed and produce viable offsprings.
All the different populations living in an area at a particular time make up a community.
All the living communities with all the non-living factors (abiotic factors) of an area make up an ecosystem. Hence, ecosystem is the correct option.
The one-celled eukaryotic organisms above are often found in freshwater ponds. What is one
characteristic they all have in common?
A Nucleus
B Cilia
C Flagellum
D Pseudopodia
Answer:
The correct option is A. Nucleus
Explanation:
The diagram in the question shows a paramecium, euglena and amoeba.
Paramecium can be describe as a fresh water animal which has a body covered with cilia. Flagellum and Pseudopodia lack in paramecium
Amoeba can be described as single celled organisms which have Pseudopodia for movement and shape changing.
Euglena is a single- celled organism capable of living is salt water as well as fresh water. It contains flagellum for movement but lacks cilia and Pseudopodia.
The structure common in all these organisms is the nucleus. Nucleus is present in every eukaryotic organism.
10 examples of biting and 10 example of piercing and chewing pests and how they affect crops
Examples of biting and chewing pests are snails, slugs, caterpillar, Helicoverpa, diamond black moth, beetles , termites, leaf worms, grass hoppers etc.
Examples of piercing insects are lace bugs, aphids, white flies, glassy winged sharp shooter, false chinch bugs, Bargrada bug, mealy bug, Eugenia psyllid, Pittosporum psyllid, Tipu psyllid etc.
Explanation:
Pests that affect crops have different feeding habits. Some pests belong to the type biting and chewing pests. These pests bite into the plant parts and chew them. This will leave circular holes in the leaves and semicircular holes in the leaf edges.
Piercing and sucking insects pierce into the plant parts and suck the sap. Removal of sap turns the plants yellow, and wilted. The growth might get stunted and in severe cases the plant may die off.
Chewing insects cause physical damage to plants by eating leaves, stems, and roots, leading to reduced photosynthesis and growth. Piercing-sucking insects damage crops by extracting plant sap and often transmit diseases to the plants.
Biting and Piercing-Chewing Pests and Their Effects on Crops
Chewing Insects:
Caterpillars (e.g., cabbage worms): Defoliate plants by eating leaves.Beetles (e.g., Colorado potato beetle): Damage foliage, stems, and roots.Grasshoppers: Consume leaves and young plants.Armyworms: Cause chewing damage to leaves and stems.Fall Webworms: Create webs and skeletonize leaves.Leafminers: Create tunnels in leaves, reducing photosynthesis.Root Weevils: Chew on roots, affecting plant stability and nutrient uptake.Cutworms: Cut off plant stems at the base.Weevils (general): Feed on various parts of plants.Earwigs: Chew on plant leaves and flowers.Piercing-Sucking Insects:
Aphids: Suck sap, causing deformed growth and transmitting diseases.Leafhoppers: Cause leaf curling and transmit pathogens.Scale insects: Weaken plants by continuous sap extraction.Mealybugs: Cause yellowing and stunted growth by sucking plant juices.Whiteflies: Excrete honeydew leading to mold growth on leaves.Squash bugs: Wilting and death of squash and pumpkin plants.Spider mites: Cause stippling and bronzing of plant leaves.Thrips: Deform flowers and leaves by sucking sap.Stink bugs: Damage fruits and vegetables by feeding and injecting toxins.Psyllids: Cause leaf yellowing and stunted growth by feeding on plant fluids.Both types of pests can seriously affect crop health and yield by directly damaging plant tissues or indirectly by transmitting diseases.
Transcription and Translation .A graduate student determined that the sequence GAT exits in a section of DNA. This code represents the amino acid aspartic acid.Will aspartic acid definitely be found in the transcribed mRNA strand? Will it definitely be found in the synthesized protein chain? Explain your answer.
Explanation:
Sequences of DNA make up genes which can have different forms called alleles. DNA is transcribed into mRNA and later translated into amino acids which are linked together by rRNA to form proteins. The sequence GAT is on the sense strand 5' → 3' direction, thus it has the same sequence as mRNA
Codons encoding aspartic acid will be found on the mRNA strand as GAT. As each odon encodes one amino acid, it will be present on the synthesised chain; mRNA codons undergo transation- this will produce Asp, aspartic acid.
Further Explanation:
The nucleic acids are comprised of smaller units called nucleotides and function as storage for the body’s genetic information. These monomers include ribonucleic acid (RNA) or deoxyribonucleic acid (DNA). They differ from other macromolecules since they don’t provide the body with energy. They exist solely to encode and protein synthesis.
Basic makeup: C, H, O, P... life on Earth is Carbon based nucleotides contain 5-carbon sugars, and nitrogen; the bases may contain single to double bond rings
All the genetic information within the eukaryotic cell is stored within the nucleus as helical DNA. This DNA is tightly wound around histones as chromosomes. Codons are three nucleotide bases, with each codon encoding an amino acid or signalling the beginning or end of protein synthesis.
RNA codons determine certain amino acids so the order in which the bases occur within in the codon sequence designates which amino acid is to be made bus with the four RNA nucleotides (Adenine, Cysteine and Uracil) Up to 64 codons (with 3 as stop codons) determine amino acid synthesis. The stop codons ( UAG UGA UAA) terminate amino acid/ protein synthesis while the start codon AUG begins protein synthesis.
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(b) The pondweed was placed in a test tube of water at 10°C.
The number of bubbles of gas produced by the pondweed in three minutes was recorded.
This was repeated with water at different temperatures.
The light intensity was kept constant for each temperature.
(i) State why the light intensity absorbed by the pondweed is not the same as
the light intensity measured by the light meter.
Answer:
As no figure but optimum temperature is directly proportional to the rate of photosynthesis ie 10 to 20 Celsius depends on plant but it's enzyme is 35 to40
put the following in order from smallest to largest: cells, tissues, organ systems, organs
1. Cells
2. Tissues
3. Organs
4. Organ Systems
Hope I helped!
~Stay golden~ :)
Answer:
Explanation:
1. Cells
2. Tissues
3. Organs
4. Organ Systems