If a small drop of tiny particles such as pollen grains are dropped into a drop of water on a microscope slide, they will appear to vibrate and spread out. The primary reason for this is
Answer:
The primary reason is that the pollen grains are being struck by water molecules that move in different directions. These strikes fluctuate and sometimes are uneven.
Explanation:
This vibration and spread out of molecules in water is called Brownian Motion. It is the result of the collision of small particles of water with big particles of pollen. As the particles of water move randomly hitting different sides of the pollen particle, at times, there will not be a coordinated movement, but as the movement of water particles is random, there will be moments when one side of the pollen particle will collide with more water particles, when this happens there is an unbalanced force that makes the pollen particle moves in a direction.
A scientist is observing cells undergoing division and identifies a cell that contains 15 pairs of homologous chromosomes. However, a new technique allows the scientist to determine that several of the chromosomes have exchanged pieces of genetic material with their homolog. The scientist now knows that which of the following is true?
A. The cell is in mitosis and has just completed crossing over
B. The cell is in meiosis II and is ready to complete the second division over
C. The cell is in meiosis and has just undergone crossing
D. The cell is in late anaphase of mitosis
Answer:
B. The cell is in meiosis II and is ready to complete the second division over.
Explanation:
Hope it helps.
Which of these statements best sums up evolution?
rapid change in species’ habits and features
rapid development of vestigial structures in a species
change in a population through new species being made
change in a population through genetic variation over time
Answer:
change in a population through genetic variation over time
Explanation:
took the test
The following models show one large cell (A) and four small cells (B).
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O
olo
O
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ОО,
O
A
B.
Which of the following states why one of the models is better for moving
more nutrients in and out of the cell?
O A. A is better because it has more surface area.
The question is incomplete and the diagram is also not given. So the diagram is attached below and the complete question is as follows:
The following models show one large cell (A) and four small cells (B).
Which of the following states why one of the models is better for moving more nutrients in and out of the cell?
A. B is better because it has more surface area.
B. A is better because it has less surface area.
C. A is better because it has more volume.
D. B is better because it has more volume
Answer:
A. B is better because it has more surface area.
Explanation:
The movement of nutrients in a cell depends on the surface to volume ratio. More is the surface to volume ratio, better will be the movement of nutrients in and out of the cell.
In the given model, small cells (B) has more surface to volume ratio as surface area of B is larger, so, the model B is better for moving more nutrients in and out of the cell.
Hence, the correct option is "A".
Answer:
B has smaller cells but more surface area than A
Explanation:
B
which type of stem cells are most limited in differentiation
Answer:
Stem cells are the every organ and tissue that in your body.
Explanation:
The Stem cell are the many different types of the place in the body part they all are time in lives different .Stem cells are the fetal development during in the body.
Stem cells are very different and critical abilities, cells very widely that can not do certain things.
There are many types of cells in their:- Tissue specific cells ,
Embryonic cells, Induced stem cells.
Tissue specific cell:- This types of cell are more specialized the Embryonic cells.
Embryonic stem cell:- This types of cell are obtained the inner cell in the human forms, this cells retain in the special laboratory conditions.
Induced cell:- This types of cell are developing and testing drugs.
The diagram shows two charged objects, A and B.
Based on the field lines, what are the charges of the
objects?
3
A: positive
B: negative
O A: negative
B: positive
O A negative
B: negative
OA: positive
B: positive
A
B)
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Save and Fit
Answer:
A: positive
B: negative
Explanation:
Hope it helps.
Answer
A is positve and B is negitive
Explanation:
g The pH of the space between the inner and outer mitochondrial membrane is ______________ the pH of the mitochondrial matrix.
Answer:
lower than
Explanation:
The protons obtained from the spit of hydrogen atoms, to protons and electrons, (which was transported to the Matrix of the mitochondria by NADH and FADH2 ) are pumped by PMF into the intramembrane space.
The constant pumps by the PMF,due to the electron transport chains set up high concentration of Hydrogen ions in the intramembrane space.If pH is -log[H+] then the high the number of H+/protons,the stronger the acidity,and lower the pH of the medium.
This set up higher electrochemical gradient compare to the matrix.Thus H+ diffuses down the gradients into the matrix.
This generate energy needed for the synthesis of ATPs by ATPase synthase in the matrix
What would cause antibodies to attack the cells of the body?
Answer:
In autoimmune diseases, such as lupus, multiple sclerosis and rheumatoid arthritis, people produce antibodies that stick to their body's own proteins and attack healthy cells.
Explanation:
The muscle that originates on the sacrum and transverse process of each vertebra and inserts on the spinous process of the third or fourth more superior vertebra is the ________ muscle.
Answer:
The muscle that originates on the sacrum and transverse process of each vertebra and inserts on the spinous process of the third or fourth more superior vertebra is the Longissimus muscle
Explanation:
The Longissimus is a group made of three muscles: longissimus capitis, longissimus cervicis and longissimus thoracis. It has the length of the vertebral column.
It is placed in the back, and as the statement says, it originates on the sacrum and transverse of each vertebra. Each of them originates at the transverse elements and insert in the costal ones.
Place in correct order the following steps in the process of appositional growth of cartilage. a: New matrix is produced and secreted. b: Chondrocytes differentiate, each in its own lacuna. c: Stem cells undergo mitosis. d: Committed cells differentiate into chondroblasts.
Answer:
c: stem cells mitosis stem.
d: the compromised cells differentiate into chondroblasts.
a: New matrix is produced and secreted.
b: Chondrocytes differ, each in its own gap.
Explanation:
The appositional growth of cartilage occurs in an appositional order, thus generating these cartilage structures to give future bone structures or mature cartilages themselves.
In the cartilage of growth of long bones this process happens.
Chondroblasts are differentiated cells that can form the extracellular matrix, and chondrocytes would be the mature form of these that are submerged in their MEC once they reach the secretion limit.
The constant cartilage of cellular, mineral and organic structures, with organic compounds predominating (almost 80 percent are collagen fibers, proteoglycans and glycoproteins), that is why this tissue has a certain elasticity.
Which of the following actions involves voluntary muscle movement?
Answer:
what are the options?
Explanation:
Voluntary muscles require a lot more energy than involuntary muscles and remain relaxed when you're not moving, such as when you're asleep.
7. Where do most of your blood component cells derive from and what are they referred to in their undifferentiated state?
Answer:
All of the cells found in the blood come from bone marrow. They begin their life as stem cells, and they mature into three main types of cells— RBCs, WBCs, and platelets.
help asap giving branlist plsss helppp
Answer:
except option 2 all of them are applied
Explanation:
The Lannister’s family went to bed one frigid winter night and were found deceased the next day. A squirrel’s nest was found in their chimney. What happened to the Lannisters?
Answer:
They died due to suffocation.
Explanation:
The whole Lannister’s family died due to the shortage of oxygen in the room because of squirrel’s nest in the chimney. Chimney is the only way for the removal of toxic gases and smoke produced from the burning of wood. The squirrel’s nest block the passage and the smoke and toxic gases stay in the house which causes suffocation and the whole Lannister’s family died.
Loyeulis,
iv. All of these
b) What do seeds need to grow into new plants?
1. Air
ii. Water
iii. Right amount of warmth
c) Potatoes grow from
iv. leaves.
Answer: air , water , right amount of warmth
Explanation:
Which reason best explains why bacteria are good at causing infections in other organisms? It would not be able to divide. Bacteria are transmitted easily and reproduce quickly. Bacteria evolve slowly as they pass on genetic information. Bacteria are easily killed by a host’s immune system or antibiotics.
Answer:
Bacteria are transmitted easily and reproduce quickly
Explanation:
Bacteria are organisms that have a single cell. The process of reproduction of the bacteria is binary fission. The parent cell divides into the daughter cell. The DNA of the parent cell gets copied and gets divided by forming the identical daughter cells. Some bacteria have nutritional values in them while the others are infectious. They can divide at an alarming rate if they receive favorable conditions. Also, they are easily communicable and transmittable. It is because of this reason that the bacteria are good at causing infections in other organisms.
Label parts A and B in this picture of saprophytes (fungi)
Answer: A- Sporangium
B- Rhizoids
Explanation:
The spread of cancer cells from one site to others in the body is known as _____.
Answer:
metastasis
Explanation:
Metastasis is the process in which cancer cells break away from the place where they first formed and travel through the bloodstream to other parts of the body where they form a new tumor.
Hope that helps.
(4.06 MC)Which statement best compares coastal ecosystems to open ocean ecosystems? a. Coastal ecosystems include abyssopelagic depths, and open ocean ecosystems do not. b. Coastal ecosystems have less sunlight, fewer nutrients, and less diversity than open ocean ecosystems. c. Coastal ecosystems have a greater range of water pressures than open ocean ecosystems. d. Coastal ecosystems have more sunlight, more nutrients, and higher levels of productivity than open ocean ecosystems.
Answer:
D
Explanation:
Answer:
D.Coastal ecosystems have more sunlight, more nutrients, and higher levels of productivity than open ocean ecosystems.
Explanation:
Compare and contrast the contributions of Neel, Pauling, and Ingram to our understanding of the genetic and molecular basis of sickle cell disease (SCD).
He demonstrated that SCD and sickle cell trait were due to the presence of abnormal 8-globin polypeptides in red blood cells. He demonstrated that the electrophhoretic mobility of B-globin from patients with SCD was different from that of healthy individuals. He demonstrated that both parents of multiple patients with SCD had low levels of sickled red blood cells. He hypothesized that SCD was a recessive trait and that the parents of patients with SCD would be heterozygous carriers. He demonstrated that the difference between B-globin polypeptides in individuals who were healthy and those with SCD is an amino acid substitution. He performed a peptide fingerprint analysis on B-globin from individuals with 84 84 and 89 88, which identified the segment of B-globin that was changed by the BS mutation. James Neel Linus Pauling Vernon Ingram
hope it helps..
Coal and petroleum products (fossil fuels) are a powerful resource of ___________ and energy. Following _________ plants and animals are buried and "stored" underground for millions of years leading to the formation of these byproducts.
Answer:
Carbon AND
DEATH
Explanation:
Carbon containing organic molecules derived from the remains of dead plants and animals on the earth million of years ago, buried deep under the sediment and rock layers are called Fossil fuels. Coal,oil,and natural gas are examples.
These underground deposits were formed million of years ago,due to the chemical reactions between relatively underground water molecules on one hand,and the earliest mic organisms viz algae,bacteria which inhabited the earth other hand.These decomposition occurred around 540 to 65milion years ago.
However,some million of later chemical reactions in the soil leads to compression of these remains underground.The degradation leads to formation of the fossil fuel precursor called Kerogen. With time Geothermal heat transforms the kerogen precursor to fossil fuel. some other kerogens are transformed to other natural gas,coal etc.
What is the allele frequency?
Answer:
Explanation:
Allele frequency is the how often or what's the percentage of a particular allele in a population. Allele is referred to as version of a gene that is located on the chromosome.
For example, a gene causing death in rats might have alleles, W and w. Each would be a separate allele and the frequency would be how often or what's the percentage of W or w that is present in the population.
Suppose we are trying to find frequency of W or w allele in a population then the formula is
Allele Frequency = [# of copies of certain allele (either W or w)] / [Total number of W and w alleles]
Now suppose we have 4 WW and 2 ww in a population.
First we count up W allele then we have (4 * 2)= 8 W (we multiplied by 2 because each organism has WW, 4 WW is short of of writing WW , WW, WW, WW)Same concept for 2ww, we have total w = 2 * 2 = 4wTotal alleles = W + w = 8 +4 =12
Allele Frequency for W = 8 / 12 = 66.67%
Allle Frequency for w = 4 / 12 = 33.33%
Hope this helps!
Which statement best describes the relationship of photosynthesis and onorgy?
The process of photosynthesis is onergy storing bocause the process converts light onorgy into chemical energy,
which is stored in the bonds of glucoso,
The process of photosynthesis is onergy-releasing because the process convorts light onorgy into froo onorgy that
can be used for cell functions.
The process of photosynthesis is onergy conserving because no onergy is used throughout the process of forming
glucose and oxygen molecules,
The process of photosynthesis is onergy-wasting because photosynthesis is an inofficient process that doplotos
the cell of energy stored in the bonds of glucose.
The process of photosynthesis is onergy storing bocause the process converts light onorgy into chemical energy,
While sitting at your desk, you drop your pencil onto the floor. You bend over to pick up the pencil. In order to straighten up and continue your exam you must use which muscles?
Answer:
Deltoid muscle
Trapezius muscle
Carpel muscle
Quadriceps
Hamstrings
Glutes
Abdominal muscles
the meaning of photosynthesis
Answer: the process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water. Photosynthesis in plants generally involves the green pigment chlorophyll and generates oxygen as a byproduct
Explanation:
Answer:
it is when a green plant or another plant use sunlight to synthesize food from water and carbon dioxide
:
Ms. Jenson is a young woman who routinely uses a variety of herbal products to treat and prevent diseases. She knows there is a strong history of type 2 diabetes in her family and has read on the Internet about drinking black tea to prevent diabetes. She asks you whether you think that would work for her. What should you tell her?Do you think it is a good option for her?What has research shown out black as a preventive treatment for diabities?where could she find evidence based information about this?
Answer:
You should be advised to use it as a complementary natural treatment in addition to insulin or oral hypoglycemic, since it must be based on quality scientific evidence.
For this you can search in search sources such as PUBMED.
Explanation:
Some research maintains that black tea is responsible for stimulating the secretion of insulin by the beta cells of the pancreas
What are the five senses? Type your brainstorm
Answer:
Sense: Smell, Taste, Touch, Sight, Hearing
Explanation:
Answer:
touch, sight, hearing, smell, taste
Explanation:
Touch is thought to be the first sense that humans develop, according to the Stanford Encyclopedia of Philosophy. Touch consists of several distinct sensations communicated to the brain through specialized neurons in the skin. Pressure, temperature, light touch, vibration, pain and other sensations are all part of the touch sense and are all attributed to different receptors in the skin.
Sight, or perceiving things through the eyes, is a complex process. First, light reflects off an object to the eye. The transparent outer layer of the eye called the cornea bends the light that passes through the hole of the pupil. The iris (which is the colored part of the eye) works like the shutter of a camera, retracting to shut out light or opening wider to let in more light.
hearing sense works via the complex labyrinth that is the human ear. Sound is funneled through the external ear and piped into the external auditory canal. Then, sound waves reach the tympanic membrane, or eardrum. This is a thin sheet of connective tissue that vibrates when sound waves strike it.
Humans may be able to smell over 1 trillion scents, according to researchers. They do this with the olfactory cleft, which is found on the roof of the nasal cavity, next to the "smelling" part of the brain, the olfactory bulb and fossa.
The gustatory sense is usually broken down into the perception of four different tastes: salty, sweet, sour and bitter. There is also a fifth taste, defined as umami or savory. There may be many other flavors that have not yet been discovered. Also, spicy is not a taste.
Briefly explain what was done in the experiment where pigeons could choose which button to peck in the Skinner box. How does this relate to self-control?
In this experiment, Skinner placed a pigeon inside a box that contained a button that when pressed released water or food. This pigeon went through periods of deprivation of water and food, but over time, he realized that when he pecked the button he had access to these two elements. Skinner called this behavior operant behavior, which is the behavior that occurs controlled by its consequences.
Although Skinner did not specifically study self-control, with this experiment, we can make a connection between operant behavior and self-control, since both are behaviors shown as a way to change the environment in which they are inserted, but this change also affects them.
what is a type of emigration where offspring move
away from their parents.
Answer:Dispersal
Explanation: This refers to offspring moving away from their parents. This prevents the offspring from competing with the parents for resources such as light or water. For example, dandelion seeds have “parachutes.” They allow the wind to carry the seeds far from the parents
Some organisms are made of single cells and live in the hot acidic environment of deep ocean vents.
Some organisms are single cells and live one the surface of your skin.
And there are small multicellular organisms that make fuzzy circular growth on old bread.
And of course, roses with pretty flowers are organisms.
And whales.
That’s a lot of diversity. So let’s say I think those creatures are just so different that they just couldn’t ALL be related to each other. Using specific traits, convince me that all of these organisms can be traced back to a common ancestor. (At least 6 well-chosen traits required for full credit.)
Write your answer in the essay space.
Answer:
All organisms are composed of cells that share a structural organization and play roles in similar biological processes.
Explanation:
All living organisms can be grouped in terms of cellular organization, functioning, and structure. These features enable us to define them as “subjects” of life. Organisms share basic biological mechanisms such as, among others, growth, homeostasis, development, energy processing, reproduction, etc. Moreover, life is also defined by the presence of essential biomolecules such as DNA, RNA, proteins and lipids. Finally, the cell is considered to be the basic unit of every life form, and organisms may be formed by one (unicellular) or more cells (multicellular). The fundamental feature of the cell is the presence of a membrane that separates it from the external environment, thereby defining its internal environment.