Answer: They don’t have microvili because they don’t need it.
Explanation:
Animal cells have this because it increase surface area and helps absorb food and water molecules.
Plant cells do not have microvilli because they do not require the same type of surface area enlargement as animal cells.
Microvilli are small, finger-like projections that extend from the surface of animal cells. They help to increase the surface area of the cell, which is important for functions such as absorption and secretion.
Whereas plant cells have a rigid cell wall that provides structural support and protection. They have evolved unique structures to meet their specific needs, such as chloroplasts for photosynthesis and a cell wall for support and protection.
So, the absence of microvilli in plant cells is not a disadvantage since they do not require the same surface area enlargement as animal cells.
Therefore, the absence of microvilli in plant cells is due to their unique structural and functional needs.
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Modern plant-breeding techniques (artificial selection in action) have reduced genetic variability in many of our most commercially valuable plants. To most people, that would generate a shrug. However, a biology student that has studied evolution understands the problem with this. Briefly explain why there is an issue with this.
Answer:
There is an issue with the artificial selection.
Explanation:
There is an issue with this artificial selection because the genetic variability is reduced when we do again and again the artificial selection. In the artificial selection, the selected genes are combined with the one another and does not allow natural fusion or combination of genes that is responsible for the genetic variability in the organisms so that's why we can say that this artificial selection is an issue that reduce genetic variability.
In cell culture experiments, purified B cells expressing IgM can be induced to switch to producing IgE by stimulating them with an antibody to CD40 (a stimulatory antibody) plus the cytokine IL-4. In an individual undergoing an immune response, these signals would normally be provided by:
Answer:
TFH cells in the germinal center
Explanation:
The Tfh cells, present in the germinal center, are responsible for maturing and stimulating the class change of immunoglobulins (such as the change from IgM to IgE). This change could stimulate the new classes of immunoglobulins to act with stimulating antibodies to produce an immune response.
It is important to point out that the germinal center is the activated point of a lymphoid follicle that contains B and T lymphocytes, which act in the memory of the cells of the immune system.
Questions 1 and 2 refer to the following statements:
I. Shortening of the chromosomes
II. Synthesis of DNA
III. Crossing over of non-sister chromatids
IV. Separation of sister chromatids
1. Which events occur during mitosis?
A) I and II only
B) I and III only
C) I and IV only
D) I, II, and IV only
2. Which events occur during meiosis I?
A) I and II only
B) I and III only
C) I and IV only
D) I, III, and IV only
A chromosome is a long DNA molecule with part or all of the genetic material of an organism. Most eukaryotic chromosomes include packaging proteins called histones which, aided by chaperone proteins, bind to and condense the DNA molecule to maintain its integrity. These chromosomes display a complex three-dimensional structure, which plays a significant role in transcriptional regulation.
Chromosomes are normally visible under a light microscope only during the metaphase of cell division (where all chromosomes are aligned in the center of the cell in their condensed form). Before this happens, each chromosome is duplicated (S phase), and both copies are joined by a centromere, resulting either in an X-shaped structure (pictured above), if the centromere is located equatorially, or a two-arm structure, if the centromere is located distally. The joined copies are now called sister chromatids. During metaphase, the X-shaped structure is called a metaphase chromosome, which is highly condensed and thus easiest to distinguish and study. In animal cells, chromosomes reach their highest compaction level in anaphase during chromosome segregation.
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Please helpppppppppp ASAP
100 extra points
Answer
answer with the help of this
Explanation:
The prevalence of CRE infections in health care settings has increased significantly in recent years, in part because these organisms are able to share plasmid-encoded resistance genes. Which method of horizontal gene transfer is most likely responsible for transfer of the plasmid between bacteria
Answer:
Bacterial conjugation
Explanation:
Carbapenem-resistant Enterobacterales (CRE) are different types of bacteria that lead to infections in healthcare settings. Moreover, a plasmid is a small piece of DNA that can replicate independently from the bacterial chromosome. Bacterial conjugation is a type of horizontal gene transfer by which plasmids are transferred from one bacterium referred to as 'donor' into another called 'recipient' by sex pili. Plasmid transfer is unidirectional and depends on physical contact between bacterial cells. In this case, it is expected that this type of DNA transport mechanism occurs among patients occupying the same rooms in healthcare settings.
how many types does the larva of silkworm moult?
Answer:
there are 6 lava of silkworm moult.
Answer:
Silkworms will undergo molting up to four times since they grow so much before becoming an adult.
Explanation:
C What is the important of making prority
Answer:
Priorities will guide you in life's decisions and keep you on track. Most importantly, priorities will give you the confidence to say "no." They help you identify what's truly needed in your life, versus what someone else feels is important.
Answer:
The importance of it are Establishing priorities is necessary in order to complete everything that needs to be done. Prioritization is important because it with allow you to give your attention to tasks that are important and urgent so that you can later focus on lower priority tasks.
In meiosis, sister kinetochores are attached to the same pole of the cell during meiosis I, and sister chromatid cohesion is released during anaphase II. What would be the likely result if sister kinetochores were attached to different poles of the cell during meiosis I and sister chromatid cohesion was released during anaphase I
Answer:
sister chromatids would migrate to opposite poles in anaphase I
Explanation:
Kinetochores are multiprotein structures that establish the attachment of spindle microtubules to the chromatids during cell division (either mitosis or meiosis). Sister chromatid cohesion at the centromeres refers to the mechanism by which sister chromatids are paired and held together during meiosis I. This process (sister chromatid cohesion) is fundamental to ensure the correct orientation of chromatids on the spindle microtubules and their subsequent segregation in meiosis II. The fusion of sister kinetochores in meiosis I underlies sister chromatid cohesion during this stage of the cell division, thereby their disruption or destruction of sister chromatid cohesion would lead to separation and segregation of sister chromatids to opposite poles of the cell in anaphase I.
Determine if the following statement is true or false and why: All organisms make their own food, but plants are the only kind to do so using sunlight. A. False, not all organisms can make their own food, only plants and some bacteria. B. False, all organisms can use sunlight to make food. C. False, plants cannot make their own food. D. True
Answer:
A. False, not all organisms can make their own food, only plants and some bacteria.
Explanation:
It's right
The description of the statement whether it is true or false is described below:
All organisms make their own food, but plants are the only kind to do so using sunlight. (False).Not all organisms can make their own food, only plants, and some bacteria. (True). All organisms can use sunlight to make food. (False). Plants cannot make their own food. (False). How do plants prepare their own food?Plants prepare their own food with the process of photosynthesis which utilizes carbon dioxide and water and synthesizes glucose in the presence of sunlight.
Plants, some photosynthetic algae, and some bacteria prepare their own food with the help of sunlight. They have a photosystem that captures the energy of sunlight in the food production mechanism.
Therefore, it is well described above.
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In the early days of life on Earth, plants were exposed to extremely high doses of ultraviolet radiation. Constant UV exposure resulted in some land plants developing narrow leaves with thick, waxy cuticles. Over many, many generations, these narrow leaves evolved into needles.
Answer:
so, what is the question?
Explanation:
hola, ecesito para ahora,
cual es la diferencia entre la alergia a la leche y le intolerancia a la lactosa?
gracias
Answer:
Una alergia verdadera a la leche difiere de la intolerancia a las proteínas de la leche o de la intolerancia a la lactosa. A diferencia de una alergia a la leche, en la intolerancia no interviene el sistema inmunológico.
Explanation:
Vaccines contains
1 point
the antigen of a pathogen
the antibody of a pathogen
the DNA of a pathogen
the DNA of human cells
Answer:
the antigen of a pathogen
The ovals above represent mangrove islands of various sizes and distances from shore. According to the MacArthur/Wilson Island Biogeography Model, which island is expected to have the LOWEST number of insect species at equilibrium
There are few island on earth which are insect free due to atmosphere and sea breeze which do not complements the insects breed.
These islands attract tourists more because of no or very few insects, tourist have no fear of getting sick during their stay on these islands.
Antarctica is mosquito free continent. The island in Antarctic ocean are mosquito and have very few insects due to lack of stagnant water available for their breeding.
Iceland, Seychelles and few other island are insect free or have very low amount of insects there. The coral island is all surrounded by water and there is no connection of this island with the land.
There is very less stagnant water and ponds which can cause the insects to survive.
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say - Aquatic animals posses air sacs.in their bodyies . Give reasons.
Explanation:
1. provides more efficient supply level of oxgen.
In an experiment that tests how
different fertilizers effect the growth of
plants, what would the DEPENDENT
variable be?
A. the growth of the plants
B. the fertilizers
C. multiple groups with the same plant and fertilizer
D. a plant without fertilizers
In this case, the correct DEPENDENT variable would be the growth of the plants (Option A).
What is the dependent variable?The dependent variable is a kind of variable that is modified along with an experimental procedure.
Conversely, the independent variable isn't changed in the experiment (in this case, the fertilizers).
In conclusion, in this case, the DEPENDENT variable would be the growth of the plants (Option A).
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explain crop modifications in your own words.
According to the theory of natural selection, why are some individuals more likely than others to survive and reproduce?
1Points
A
Some individuals pass on to their offspring new characteristics they have acquired during their lifetimes.
B
Some individuals are better adapted to exist in their environment than others are.
C
Some individuals do not pass on to their offspring new characteristics they have acquired during their lifetimes.
D
Some individuals tend to produce fewer offspring than others in the same environment.
draw a flow chart showing the spread of disease.
Answer:
hello
Explanation:
can you please tell me which disease
What does seafloor spreading mean
Answer:
The formation of fresh areas of oceanic crust which occurs through the upwelling of magma at mid-ocean ridges and its subsequent outward movement on either side.
What type of evolutionary adaptations did plants acquire to allow them to grow in areas that were not directly on a water source? A. Angiosperms evolved flowers, which could catch rainwater, reducing the dependence on ground water sources. B. Vascular seedless plants evolved specific structures to transport and hold fluids, reducing dependence on water sources. C. Gymnosperms evolved seeds, which they could alter to need less water. D. Non vascular plants evolved chloroplasts to allow them to get energy from the sun, instead of relying on water for energy.
Answer:
B
Explanation:
In the given scenario, vascular seedless plants evolved specific structures to transport and hold fluids, reducing dependence on water sources. The correct option is B.
What is vascular plants?A plant that basically have a specialized conducting system which entails xylem and phloem, the tracheophyte is referred to as vascular plants.
Vascular plants are widely recognized as tracheophytes. Vascular tissues are xylem and phloem for conduction of water and food respectively.
They allow plants to grow in height in the air without even drying out. Vascular plants also have roots, stems, and leaves.
Seedless vascular plants are the ones which have vascular tissue but though do not produce seeds as well as flowers.
In such vascular plants, for instance, ferns and horsetails, the plants multiplies using haploid and unicellular spores on the place of seeds.
Thus, the correct option is B.
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A pure substance containing only one kind of blank hurry
Answer:
elements
Explanation:
Question 7
All living things are made of cells.
Lion
True
False
Answer:---
True. Cell theory makes three major assertions: 1. All living things are made of cells. 2. Cells are the smallest unit of life. 3. Cells can only...
The new Hazard Communication Standards provide teachers and students the right to __________ chemical hazards.
The new Hazard Communication Standards provide teachers and students the right to manipulate chemical hazards.
Chemical hazards are non-biological substances that can cause damage to health. These are used in different enterprises, companies, school, universities and laboratories for different purposes such as cleaning, disinfection, scientific experiments, among others. When handling them, employees are exposed to them and are vulnerable to harm from these chemicals.
There are many types of hazardous chemicals to be wary of, such as:
Carcinogens NeurotoxinsAcids Systemic toxins Asmogens Silica dust LeadIn the workplace, exposure to these substances represents a real occupational hazard and there must be regulations to ensure that they are safe to handle.
The Occupational Safety and Health Administration (OSHA) is the agency of the U.S. Department of Labor which determined the Hazard Communication Standards. This is a document with the necessary information to study the hazards of the chemical substances used by different employees in the companies, so that they are aware of the dangers of these substances. These employees have the right to know exactly what compounds they handle and the risks involved in their use as well as the precautions and care to be taken.
Therefore, by having these safety standards in place in schools and universities, teachers and students have the possibility and the right to handle chemical hazards safely to be able to conduct the class normally and learn what is necessary.
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25 puntos ayudame biologia gracias
Answer:
no puedo entender tu idioma
reaccionar unos con otros navegar por Internet y buscarlo
Please help me with this on the picture
cual es el productor del que más consumidores primarios se alimentan
Answer:
please let us know what you mean in English
Answer:
Plantas o Algas son unos productos que consumen.
Explanation:
blood flows through many small tubes if the dialyser. what is the significance of this
Answer:
Blood flows through smaller tubes to mimic the actual rate of blood flow in the body. This makes the dialysis machne safe for the body. Th dialysis machine can also adjust pressure in accordance of a persons blood pressure
Explanation:
9. The organs which are incompletely developed (rudimentary) and generally non-functional or without any use are called vestigial organs. Which of the following is a vestigial organ? a. Intestinal villi b. Papillae c. Vermiform appendix d. None of the above
Answer:
Vermiform appendix is answer maybe
Which tools would I use to heat 400 mL of water
Answer:
ruler, graduated cylinder
Explanation:
the results of an experiment can be validated through replication true or false
Answer:
True through replication
Answer:
this is true
Explanation:
