Answer:
65.4
Explanation:
To find the average, add all the values together and divide by the number of values (3)
[tex] \frac{65.4 + 65.3 + 65.5}{3} [/tex]
average = 65.4
Question 1
Which of the following can best explain why eukaryotic cells must use mechanisms other than diffusion to
transport materials around the cell?
In eukaryotic cells, materials can flow through microtubules
Enzymes cannot attach to eukaryotic membran
Random movement of molecules is not fast enough to disperse through the larger eukaryotic cell volume,
In eukaryotic cells, internal membranes get in the way and block diffusion
Answer:
Random movement of molecules is not fast enough to disperse through the larger eukaryotic cell volume,
Explanation:
Eukaryotic clels are much bigger than prokaryotic cells. The latter may be 0.5 um while the former may be 100 um (which is more than 10X in comparative size). Prokaryotic cells, therefore, have a larger surface area to volume ration that suits them to use diffusion to eliminate waste and take up nutrients. However eukaryotic cells cannot adopt this mechanism due to their smaller surface area-to-volume ratio which would cause them to accumulate waste to toxicity levels. Eukaryotic cells, therefore, use additional vesicle transport to take up nutrient and eliminate waste in bulk.
2. Factors that may affect variables are called
a. experiments.
b. hypotheses.
C. theories.
d. variables.
Experiments test hypotheses without explaining underlying causes. Hypotheses propose explanations, while theories, supported by evidence, provide comprehensive explanations, elucidating how factors interact. For instance, testing fertilizer effects on plant growth may support a hypothesis but a theory would explain why. Here option C is correct.
Experiments are controlled procedures conducted to test a hypothesis. They don't explain why variables might be affected, just if they are affected.
Hypotheses are proposed explanations for a phenomenon, but they don't explain the underlying factors that might be causing it.
Theories are well-established explanations for a phenomenon that are supported by evidence. They often explain how different factors can interact to influence variables.
For example, imagine you're studying the effect of fertilizer on plant growth. You might conduct an experiment to see if plants fertilized with different amounts of fertilizer grow taller. The results of the experiment might support a hypothesis that fertilizer increases plant growth, but it wouldn't explain why.
A theory of plant growth, on the other hand, might explain that fertilizer provides nutrients that plants need to grow taller. This theory could then be used to explain why the plants in your experiment grew taller when they were fertilized. Here option C is correct.
In an experiment, factors that might influence the dependent variable beyond the independent variable being tested are called control variables, and they are crucial for ensuring accurate experimental results.
Explanation:Factors that may affect variables in an experiment are called control variables. In scientific experiments, the variable that is being measured is known as the dependent variable, which is the outcome variable affected by the manipulation of another variable. The variable that the experimenter changes to observe its effects on the dependent variable is called the independent variable. When designing an experiment, it is crucial to also consider and control any additional factors or variables that could influence the dependent variable, beyond the independent variable being tested. These are often referred to as control variables, and they help ensure that the experiment measures the effect of the independent variable as accurately as possible without interference from other factors.
shientists are consistantly learning more and more about fossils because
Answer:
Scientists are constantly learning more about fossils to understand the evolution of earth and other living species.
Explanation:
It helps to study the structure of the organisms that are already extinct. Fossils are the conserved remains or traces of animals, plants, and other organisms that exist no more.
Fossils are the significant proof for evolution as it demonstrate that organism on earth was unique from the organism found on earth today. It is also used to study the tectonic history.
Cells can conduct many tasks, including which of the following?
duplicate themselves
convert energy
selectively exchange materials
all of the above
Answer:
all of the above
Explanation:
cells are multiple taskers
a blastocyst is a group of cells that forms after a human egg is fertilized. The blastocyst consist of two types of cells. Some of these cells develop into all of the cells of a growing fetus. What do the other cells develop into?
A. The Umbilical Cord
B. The Placenta
C. The Embryo
D. The Fetus
The blastocyst is split into two cell types: the inner cell mass, which becomes the fetus, and the trophoblast cells. The latter transforms into the placenta, supplying nourishment and removing waste for the developing fetus.
Explanation:A blastocyst is an early stage in human embryonic development that forms a few days post-fertilization. The blastocyst comprises two kinds of cells: the inner cell mass (ICM) and the trophoblast. While the ICM cells develop into the embryo (eventually becoming the fetus), the trophoblast cells are responsible for developing into another crucial part of the gestational system. These cells transform into the placenta, the organ that provides nourishment to the growing fetus and removes waste products.
So, to answer your question, the other cells - the trophoblast cells in the blastocyst - develop into the placenta (Option B).
Learn more about blastocyst here:https://brainly.com/question/36298318
#SPJ12
Stars on the upper left end of the main sequence differ from those on the lower right end in what way
Answer:
The answer is B.
Explanation:
Final answer:
Stars on the upper left end of the main sequence are high-mass, bright, and hot while those on the lower right end are low-mass, cooler, and less luminous. The most massive stars leave the main sequence early to become red supergiants, and over time, less massive stars follow, becoming red giants.
Explanation:
Stars on the upper left end of the main sequence are significantly different from those on the lower right end. The main sequence stars are characterized by a continuum of stellar masses and their corresponding luminosity and temperature. Stars on the upper left are high-mass stars with high temperatures and high luminosities, making them very bright and hot. Conversely, stars on the lower right are low-mass stars, which are much cooler and less luminous, placing them among the dimmest visible stars.
As time goes on, star clusters change and evolve. Within a cluster, you can notice that after approximately 4 billion years, many stars - even those just a few times more massive than the Sun - will leave the main sequence to become red giants or super giants. The most massive stars leave the main sequence relatively quickly and eventually make their way to becoming red supergiants, while less massive stars become red giants. This evolutionary path is seen on the H-R diagram where stars move from the main-sequence band to the upper right as they become simultaneously more luminous and cooler.
what are two ways scientists can describe the quality of measurements
Answer:
To describe a scientist as skeptical means that they question both existing ideas and new hypotheses. Skepticism is considered a valuably quality in a scientist because they must be able to evaluate the strengths and weaknesses of a hypothesis.
Precision and validity of the measurement are the two ways scientists can describe the quality of measurements.
Explanation:
The quality of the measurement from time innumerable is based on quantity and magnitude. The scientists describe the quality of the measurements by comparing the existing ideas and new hypotheses.
Quality of measurements can be done by precision and validity of the measurement. Measurements are derived by performing calculations, applications to derive accuracy and precision towards attaining the quality of measurement.
what would occur to an autotroph population if the number of herbivores dramatically increased
Answer:
The population of autotroph's would decrease.
Explanation:
Herbivores feed on plants and that is what an autotroph is, but if the amount of herbivores increased, there would be more animals to eat more of the plants.
Question 22
1 pts
After placing a slide on the microscope stage, what should
be manipulated first to make sure the field of view has
adequate light?
The eyepiece
The diaphragm
The high-powered objective
The fine adjustment knob
FERN
-
DELL
LET
LLLLL
POR
TE
-
-
TE
Answer:
THE DIAPHRAGM
Explanation:
The diaphragm is present beneath the stage and above the condenser in a microscope. It is that rotating disk that can be seen just underneath the stage. The function of the diaphragm is to control the amount of light once the specimen or slide is placed on the microscope.
The diaphragm consists of holes of different sizes. These holes majorly function in varying the amount and intensity of light on the slide or specimen.
how does surface-to-volume ratio relate to the size of a cell
A. small cells have a greater surface-to-volume ratio than larger cells
B. surface-to-volume ratio remains constant as cells increase in size
C. there is no relationship between surface-to-volume ratio and cell
D. small cells have a smaller surface-to-volume ratio than larger cells
Answer:a
Explanation:
The surface-to-volume ratio decreases as cells increase in size, affecting their ability to exchange materials efficiently. Small cells have a greater surface-to-volume ratio than larger cells, enabling more effective nutrient uptake and waste removal.
The relationship between the surface-to-volume ratio and the size of a cell is significant in understanding how cells function and survive. A cell's surface area-to-volume ratio is crucial for its ability to acquire nutrients, dispose of waste, and overall interact with its environment. As cells grow in size, their surface area-to-volume ratio decreases.
Small cells have a greater surface-to-volume ratio than larger cells. This higher ratio is advantageous because it allows for more efficient exchange of materials between the cell and its external environment. The surface of the cell is where nutrients are absorbed and waste is expunged, so a larger surface area relative to the cell's volume enables these processes to occur more effectively.
In contrast, as cells increase in size, the surface area does not keep up proportionally with the volume, which leads to a decreased surface-to-volume ratio. This condition can limit the cell's efficiency in exchanging materials, potentially inhibiting growth, function, and reproduction. Therefore, cells often divide when they reach a certain size to restore a more favorable surface-to-volume ratio. This principle explains why smaller cells are generally more effective at nutrient uptake, waste removal, and overall metabolic function compared to larger cells.
Harrison wanted to find out what soil works best for growing roses. He grew them in potting soil, clay, sand, and soil he found outside his yard. After one week, he measured their height and how many leaves they had. What are the independent variable, dependent variable, control, and constants?
Final answer:
The independent variable in Harrison's experiment is the type of soil, the dependent variables are the height and number of leaves of the roses, and the control is a separate group of roses grown in a standardized soil. The constants include factors like water, sunlight, temperature, and planting conditions.
Explanation:
The independent variable in Harrison's experiment is the type of soil (potting soil, clay, sand, and soil found outside his yard), as this is the factor that is being changed or manipulated. The dependent variables are the height and number of leaves of the roses, as these are the variables that are measured and are expected to be influenced by the type of soil. The control in this experiment would be a separate group of roses that are grown in a standardized soil that is known to be suitable for rose growth.
The constants in Harrison's experiment would be factors that are kept the same across all groups of roses, such as the amount of water, sunlight, temperature, and planting conditions. These constants ensure that any differences observed in the dependent variables can be attributed to the independent variable (type of soil) and not other factors.
Which material forms the organic portion of soil
TIME REMAINING
54:50
Jennifer attends school everyday, but when she goes home she decides not to do her homework or study for tests, so
she has poor grades. Which of the following statements about Jennifer is true?
A. Jennifer is not fulfilling her duties to become a productive citizen.
B. Because Jennifer is attending school, she is fulfilling all of her educational civic duties.
C. Jennifer could face consequences for not obeying the law.
D. Jennifer is focused on critical thinking and problem solving.
Please select the best answer from the choices provided
Please select
US
Answer:
the answer is A
Answer:
it's A
Explanation:
Lipids are important to living things for all of the following reasons, EXCEPT that they are
Select one:
a. used for insulation in Arctic animals.
b. used for long-term energy storage in hibernating animals.
c. needed to form cell membranes.
d. chained together to form proteins.
Answer:
D
Explanation:
Proteins are not made of lipids chained together but rather of amino acids chained together. Lipids are made of fatty acid chains joined to various molecules - like glycerol and phosphate that make phospholipids - Phospholipids make up the cell membrane of most cells. Fats are deposited under the dermis of the skin for insulation and this layer is thicker in animals that live in the cold regions. During starvation, these fats are taken from their reserves and broken down to provide energy for the body.
Two genes for the same trait are compared. Which one is not an example of a mutation?
In the first, the series is adenine followed by two thymine; in the second, adenine is followed by two thymine.
In the first, the series is cytosine - adenine - thymine; in the second, it is cytosine - adenine - adenine.
The first has thymine where the second has a guanine.
The first has a series of three nucleotide bases; the other has a series of four.
Answer:
The cytosine-adenine-adenine pair is not an example of mutation.
Explanation:
In the base pairing of DNA, adenine bonds only with thymine and guanine bonds with cytosine. As guanines and adenines are purines and thymine and cytosine are pyrimidine in DNA, and due to their structure, there is only small space in between them to fit a purine and pyrimidine and not more than that.
Therefore, these constructions of two adenines are not possible with cytosine. Thus, this cannot be an example of mutation.
Jason wanted to find out what fertilizer worked best for growing marigolds.he put miracle grow on one, scotts fertilizer on one , and no fertilizer on another what is the iv,dv,,contol
Answer: Independent variable is type of fertilizer
Dependent variable is growth of marigold
Control is a marigold with no fertilizer
Explanation:
Independent variable can be defined as the factors which the experimenter can control and the the dependent variable depends on the independent variable.
The dependent variable is growth of marigold. Type of fertilizer will determine growth of marigold that which of the following fertilizer is best for the growth of marigold.
Controlled can be defined as the factor which can minimize the effect of variable other than independent variable.
How does a law different from a theory
Answer:
a theory may be outdated or replaced. Law can't be replaced or outdated.
Explanation:
A hypothesis is a limited explanation of a phenomenon; a scientific theory is an in-depth explanation of the observed phenomenon. A law is a statement about an observed phenomenon or a unifying concept,
How many electrons does an atom of carbon have?
Answer:
2, 4
Explanation:
Answer:
six electrons
Explanation:
HELP PLEASE!!!!!!!!! What is the difference and similarities between convection, conduction and radiation?
Answer:
Well these are all ways to move heat from one thing to another. However, the ways the heat is moved is different in each way.Which factors are used to differentiate climate regions? Check all that apply. rainfall plant life animal life temperature wind
Answer:
rainfall
temperature
Explanation:
To differentiate climate regions, factors such as rainfall, temperature, wind, along with plant and animal life should be considered. Abiotic factors, including elevation, latitude, and wind systems, significantly influence the climate, which in turn affects the distribution of biomes. Variation in these elements results in diverse climates across different geographic areas.
Explanation:Factors used to differentiate climate regions include rainfall, temperature, wind, as well as plant life and animal life. These are crucial elements that define the weather patterns and overall climate of a region. Climate is the statistical summary of temperature, humidity, atmospheric pressure, wind, rainfall, and other meteorological measurements in a given region over long periods. Climate factors like rainfall, temperature, and wind are abiotic factors that significantly influence the distribution of biomes in various regions.
Different abiotic factors, especially temperature and precipitation, account for the variations in climate across various biomes. Factors such as elevation, latitude, wind systems, ocean currents, the position on a continent, and mountain barriers also play pivotal roles in influencing a region's climate. For example, high elevations typically have cooler temperatures and wind systems can bring about various weather patterns, leading to different climates in adjacent regions.
Sonu' s mother served a glass of hot milk before his going to school.As sonu was in a hurry he forgot to drink the milk. Unfortunately his mother has also gone out. When they came back home, sonu noticed the changes in the milk,which was no more a milk,but set into a thick substance called curd.
Based on this situation answer the following questions:
a. What is this process of setting milk into curd known as?Is this a physical/chemical change?
b. Is this change harmful ?
c. How does it happen?
Its your choice that whether you want to answer all the 3 questions or just 2 of them.
Answer:
A.) Chemical B.) Yes, it is very harmful. C.) It was out for around eight hours and was hot making the chemical change happen faster.
Explanation:
It is chemical because you cannot change it back to its original form
Please dont give me brainliest btw
Final answer:
The setting of milk into curd is a chemical change known as fermentation and is not typically harmful. It occurs when specific bacteria convert lactose into lactic acid, leading to the coagulation of milk proteins into curd.
Explanation:
The process of setting milk into curd is known as fermentation, which is a type of chemical change. The transformation of milk into curd involves the conversion of lactose into lactic acid by the action of bacteria, which alters the chemical composition of the milk, causing the milk proteins to coagulate and form curd.
Is this change harmful? The answer is generally no, as this process of fermentation is typically how dairy products like yogurt and cheese are made, and consuming these products is a part of many healthy diets. However, if the milk was curdled due to spoilage and not in a controlled fermentation process, it could be harmful to consume.
To explain how it happens; Adding a fermenting agent, often a bit of preformed curd containing microbes, to warm milk starts the process. These microbes consume lactose in the milk and produce lactic acid, which reduces the pH and causes the milk to coagulate, forming curd. The conditions surrounding this process, such as temperature and time, can affect the outcome and texture of the curd.
Find the mass of a book that has weight of 14.7 newtons.
To find the mass of a book that weighs 14.7 Newtons, we divide this weight by the acceleration due to gravity, 9.8 m/s², resulting in a mass of approximately 1.5 kilograms.
Explanation:In order to find the mass of an object from its weight, we use the formula: mass = weight / gravity. Gravity on Earth is about 9.8 m/s².
To find the mass of a book that weighs 14.7 Newtons, we have to divide the weight by the acceleration due to gravity. This results in: mass = 14.7 N / 9.8 m/s² = 1.5kg.
So, the mass of the book is approximately 1.5 kilograms.
Learn more about Calculation of Mass from Weight here:https://brainly.com/question/38316598
#SPJ3
Identify the process used to form the covalent peptide bonds that join amino acids into a polypeptide.
Answer:
Condensation reaction
Explanation:
Covalent peptide bond is formed between two amino acids. It is formed by condensation reaction which is also called as dehydration synthesis reaction. One molecule's carboxyl group reacts with other molecule's amino group releasing a water molecule. This CO-NH bond is called as peptide bond or amide bond and an amide molecule is formed as a result.
An amide bond shows resonance which allows its stabilization and versatility of molecule in different environment. The amino acids link together via condensation reaction to form larger polypeptide chains.
Which observation can BEST be explained by the scattering of light
Answer: Examples of scattering of light: light, sound, or moving particles
Explanation:
Answer:
A red rainbow
Explanation:
A red rainbow also know as a monochrome rainbow, appears rarely at sunrise or sunset. During this period of the day, sunlight travels through longer paths of the lower atmosphere and shorter wavelenghts such as blues and greens scatter through the journey leaving the remaining light richer in reds and yellows, which create a beautiful red rainbows.
Which rock has the highest metamorphic grade
Answer:
Gneiss
Explanation:
The Gneiss rock is the highest grade metamorphic rock, contains bands of easily visible quartz, feldspar, and/or mica.
Answer:
The correct answer is Gneiss.
Explanation:
Metamorphic rocks refer to the rocks that get modified due to pressure, heat, and chemical procedures, generally while buried deep underneath the surface of the Earth. Getting exposed to these extreme conditions change the texture, mineralogy, and chemical composition of the rocks.
There are two fundamental kinds of metamorphic rocks known, these are foliated metamorphic rocks like gneiss and non-foliated metamorphic rocks like quartzite. Of the metamorphic rocks, the highest grade metamorphic rock is gneiss. It exhibits a banded appearance and is formed of granular mineral grains. It usually comprises enough amount of feldspar or quartz minerals.
Which organism is most likely 10 centimeters in size?
A. tree
B. ant
C. bacteria
D. lizard
some bugs can walk on the surface of water because the atteraction between water molecules is strong enough to hold us the bug. What do we call the attraction?
Answer:
Surface Tension
Explanation:
It is the combination of the legs not being wetted and the surface tension. The legs of water striders are hydrophobic. Water molecules are strongly attracted to one another. This is due to "hydrogen bonding": a proton in water is shared between two oxygen atoms of two water molecules.
The attraction that allows bugs to walk on water is called surface tension, a result of cohesive forces among water molecules like hydrogen bonding.
Explanation:The attraction that allows certain bugs to walk on water is called surface tension. Surface tension is a phenomenon in physics, where the surface of liquids, in this case water, behave as if they are covered with a stretched elastic sheet. This is due to the cohesive forces, specifically hydrogen bonding, among the water molecules.
For bugs that walk on water, their weight is sufficiently low so that the surface of water is not broken. These bugs also distribute their weight evenly across multiple legs, allowing them to exploit this physical property of water effectively.
Learn more about Surface Tension here:https://brainly.com/question/33741057
#SPJ2
Need help with cactus BIG POINTS
Okay so my moon cactus was rotting so i did what google said and cut the head off.
i really love my moon cactus so please tell me what i should do next, tips recommendations or what i did wrong needs to be very precise and correct because i want my cactus to turn into another cactus please help
After cutting the rotting head off the moon cactus, let the cut dry and callous over before planting in fresh, well-draining soil. Water sparingly and provide bright, indirect light. With proper care, the cactus may grow new heads or pups from the original base.
If your moon cactus was rotting and you've already cut the head off, the next steps are crucial for its recovery or propagation. First, make sure that the cut area is clean and dry to prevent further rot. Allow the cutting to callous over for a few days before attempting to re-root it.
Once the cut has healed, you can place the cactus in a new pot with fresh, well-draining soil. Ensure the pot has good drainage holes. Water sparingly, only when the soil is completely dry, to prevent overwatering, which is a common cause of rot.
Keep the cactus in a warm, brightly lit area but out of direct sunlight until it establishes new roots. This process can take several weeks. If the original base of the rotting cactus is healthy, you can also let it callous and it may grow new heads or pups.
Tips for Successful Moon Cactus Growth:
Use a well-draining cactus mix to prevent water retention that can cause rot.Water sparingly to keep the soil moist but not wet.Provide bright, indirect light for your cactus.HELP !!
What are the three groups of atoms that make up amino acids called?
O
A. Phosphate, sugar ring, nucleotide base
O
B. Carbon, hydrogen, oxygen
O
O
C. Hemoglobin, oxygen, iron
D. Carboxyl group, amino group, side chain
Answer:
Carboxyl Group, Amino Group and Side chain
Explanation:
An amino acid consists of three parts which are- carboxyl group, amino group and a side chain.
What is amino acid and what is its structure?• Amino acids are the building blocks of proteins and proteins in turn are macromolecules that are important for living beings as they help in maintaining structure, function and regulation of body.
• The structure of amino acid consists of a central chiral carbon (-C*), a hydrogen atom (-H), amino group (-[tex]NH_{3}[/tex]), carboxyl group (-COOH) and a side chain (-R)
• The side chain (-R) is what makes up different kind of amino acids. There are 20 types of amino acids.
Therefore, option (d) Carboxyl group, amino group, side chain is correct.
To learn more about amino acids, refer:
https://brainly.com/question/7459905
#SPJ2
Which of the following summarizes the law of conservation of mass when dealing with a chemical change?
A. The total mass of the reactants is greater than the total mass of the products
B. The total mass of reactants is less than the total amount of the products.
C. The total mass of the reactants equals the total mass of the products.
D. Matter can’t change form.
Final answer:
The law of conservation of mass states that the mass of reactants equals the mass of products during a chemical reaction, meaning matter is conserved and not created or destroyed. Thus, option C is correct.
Explanation:
The correct answer to the question is: C. The total mass of the reactants equals the total mass of the products. This statement summarizes the law of conservation of mass, which holds that during any chemical reaction, matter is neither created nor destroyed, meaning that the mass of the substances before the reaction (the reactants) must be the same as the mass of the substances after the reaction (the products).
For example, when hydrogen gas reacts with oxygen to form water, the mass of hydrogen and oxygen before the reaction is equal to the mass of the water produced after the reaction. This demonstrates that the total mass is conserved throughout the process.
In summary, this fundamental principle ensures that during a chemical change, the total mass remains constant, illustrating that in closed systems, mass can change form but is conserved.