Considering the lab procedure to determine the permeability of molecules based on size:
molecule size is a variable the material used as the membrane is constantWhat are variables and constants in an experiment?
A quantity whose value can vary is said to be a variable.
An unchanging number is called a constant.
Any experiment must involve methodically changing one quantity's value in order to observe its impact on another. The independent variable is the amount that the experimenter decides to alter.
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Need this for biology homework
Answer: A. All components work together
How many lymphatic trunks are normally found in the body?A. 11B. 12C. 13D, 14
The right lymphatic artery and the bronchus are the ducts in the body. Jugular lymph trunks, descending aorta lymph trunks, Broncho mediastinal capillary trunks, and lumbar lymph trunks are the four pairs of lymph trunks.
In the human body, however many lymphatic tubes are typically present?There are six total. Right lymphatic conduit and thoracic duct are formed when the lymphatic trunks intersect. What is larger and longer on the left (collection duct). It starts at the level of second lumbar vertebra, just anterior to the spinal column below the diaphragm.
What do the body's lymphatic trunks look like?Collecting vessels come together to form lymphatic trunks. The nine trunks, which drain lymph from the specified locations, Each of which is found as a single gastrointestinal trunk and in twins left and right, respectively, with each aspect of the body.
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true or false. In the ocean surrounding Antarctica, there are fish that
survive the cold water by using a molecule made of glycoproteins that circulates the blood and keeps it from freezing. Certain kinds of worms that live in the Arctic ocean also make antifreeze proteins that help them live in icy water.
True There are fish that can withstand the chilly water in the oceans surrounding Antarctica by using a glycoprotein-based molecule which circulates your blood and prevents it from freezing.
When related species arise from a single ancestor, how much pattern of evolution results?If two species with comparable environmental requirements have many physical characteristics but have distinct biological progenitors, convergent evolution may have produced these similarities.
Are there any common ancestors among the Galapagos tortoises?Despite having a common ancestor, the Galapagos tortoises have different neck lengths in order to best access the food they require in their environment. Ostriches and elephants both are native to the African savannas. They both possess the same quality.
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kentucky bluegrass forms seedheads only in the spring.
Is this statement true or false?
It is accurate to say that only in the spring does Kentucky bluegrass produce seedheads.
Which of the following best represents the decreasing size of sand, silt, and clay?Consequently, the sequence shows a correct arrangement of soil particles from smallest to largest in terms of particle size. Silt, sand, clay, and gravel. Annual bluegrass often has a paler green hue than Kentucky bluegrass.
Heat affects bluegrass growth?Cool-season grass known as Kentucky bluegrass thrives in the fall, winter, and spring when the weather is mild. The heated summer months inhibit its growth. Although Kentucky bluegrass will tolerate little shade, it loves direct sunlight.
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Why do we think that male Neanderthals mated with non-African ancestral Homo sapiens?Because Neanderthal mtDNA sequences are present in the human gene pool, and Neanderthal nuclear DNA sequences are not.Because neither Neanderthal mtDNA sequences nor nuclear DNA sequences are present in the modern human gene pool.Because both Neanderthal mtDNA sequences and nuclear DNA sequences are present in the modern human gene pool.Because Neanderthal nuclear DNA sequences are present in the human gene pool, and Neanderthal mtDNA sequences are not.
Option d) Because Neanderthal nuclear DNA sequences are present in the human gene pool, and Neanderthal mtDNA sequences are not.
The researchers hypothesized that there could be a connection between a species' digit ratio and sexual strategy because humans are often monogamous. If they are correct, early modern humans and modern humans were both somewhat less monogamous than Neanderthals, who had ratios that fell between the two groups (0.928).
About 100,000 years ago, as the earliest groups of modern humans left Africa, they encountered and interbred with Neandertals, maybe in the fertile Nile Valley, along the Middle Eastern coast, or in the formerly lush Arabian Peninsula.
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Full Question: Why do we think that male Neanderthals mated with non-African ancestral Homo sapiens?
Because Neanderthal mtDNA sequences are present in the human gene pool, and Neanderthal nuclear DNA sequences are not.Because neither Neanderthal mtDNA sequences nor nuclear DNA sequences are present in the modern human gene pool.Because both Neanderthal mtDNA sequences and nuclear DNA sequences are present in the modern human gene pool.Because Neanderthal nuclear DNA sequences are present in the human gene pool, and Neanderthal mtDNA sequences are not.What does delivers oxygenated blood and other nutrients to body cells?
The circulatory system delivers oxygenated blood and other nutrients to body cells.
What is blood?The circulatory system is a network of blood vessels that includes the heart, arteries, veins, and capillaries. The heart pumps oxygenated blood to the body's organs and tissues through the arteries, which branch into smaller arterioles and eventually into capillaries. Capillaries are the smallest blood vessels and are responsible for the exchange of oxygen, nutrients, and waste products between the blood and the body's cells. Oxygen and nutrients diffuse from the capillaries into the surrounding tissues, while waste products, such as carbon dioxide, diffuse from the tissues into the capillaries. After exchanging materials with the cells, the blood returns to the heart through the veins, which merge into larger venules and then into veins. The blood is then pumped back to the lungs, where it releases carbon dioxide and picks up oxygen to begin the process again.
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how bruise formed by collection of blood at the puncture site?
A bruise occurs when a blood vessel is damaged and blood escapes into the towel under your skin. The pooling of blood causes a abrasion that's generally darker than the girding skin.
Blood collects in the capillaries and leaks out sluggishly to beget the characteristic black- and-blue( or grandiloquent) mark. A bruise may also form if medical professionals fail to apply enough pressure to a needle when withdrawing it from a tone. This companion discusses why bruises appear after blood birth and how to reduce the chance of bruising. During blood delineation, a phlebotomist inserts a small concave needle into the tone in your arm to remove a blood sample. This temporarily damages the blood vessel wall filling, causing blood from the damaged tone to settle under the skin.
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In which type of classification system are names assigned only to groups that include a common ancestor and all of its descendants?A. a system that groups organisms based solely on similar morphologiesB. a system that groups organisms based on similar roles in the environmentC. a system based entirely on evolutionary historyD. a system based solely on cellular structures
Names are only given to groups that have a common ancestor and all of their descendants, or under a system that is solely based on evolutionary history.
Only groups with a common ancestor and all of their descendants are given names in what kind of classification system?A monophyletic taxon is one that contains the most recent common ancestor of a collection of organisms as well as all of its offspring [as in (a)]. These groups are sometimes referred to as holophyletic.
Additionally, a taxon that includes the most recent common ancestor but not all of its descendants may be considered paraphyletic [as in (c)]. One who does not include the common ancestor of all members of the taxon is said to be polyphyletic [as in (b)].
Mammalia and Aves, which are recognised as all having feathers or fur, are examples of well-known monophyletic taxa. Pisces and Reptilia are two examples of paraphyletic taxa. Pisces includes all ray-finned fish but excludes terrestrial descendants of fleshy-finned fish, and Reptilia includes all scaly tetrapods but includes mammals and birds without their modified scales.
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arrange the following types of microorganisms in the order in which they evolved on earth?
The order of the organisms in which they evolved on the earth is: anaerobes, anoxygenic phototrophs, oxygenic phototrophs, aerobes, multicellular organisms.
Anaerobes refers to the organisms who can survive in the absence of oxygen. In fact, these organisms die in the presence of oxygen. The example of anaerobes is: Fusobacterium, Prevotella, Bacteroides, Actinomyces, Clostridia, etc.
Oxygenic phototrophs are the organisms who perform photosynthesis by using the sunlight energy and water. These organisms consist of the photosystems to absorb the light energy. The essential pigment for photosynthesis is chlorophyll. The examples of such organisms are: green plants, algae and cyanobacteria.
The given question is incomplete, the complete question is:
Arrange the following types of microorganisms in the order in which they evolved on earth?
multicellular organisms, anaerobes, oxygenic phototrophs, aerobes, anoxygenic phototrophs
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What are the stages of photosynthesis in order?
The Calvin cycle reactions are organized into three major stages: carbon fixation, reduction, and molecule regeneration.
Photosynthesis takes place in two steps. The chloroplast absorbs energy from the sun during the first step. During this stage of the process, water is utilized, and oxygen is produced. Carbon dioxide is consumed in the second stage, and glucose is generated. C3, C4, and CAM are the three basic kinds of photosynthesis (crassulacean acid metabolism).
I had to recall some of their pathways and mechanisms in college, but I'll focus on what gives one an advantage over another and which crops, forages, and weeds have specialized C3 and C4 photosynthesis.
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If you started with a 125g sample of u-235, how much of the sample would be remaining after 3 half-lives and how many years would have passed?.
An exponential function is defined as a function whose value is a constant raised to the power of an argument is called an exponential function.
Exponential functions are commonly used in the biological sciences to model the amount of a particular quantity being modeled, such as population size, over time. Graphs of experimental data are usually drawn with time on the x-axis and the quantity on the y-axis.
Half-life (t½) is the time required for a quantity of substance to reduce to half of its initial value.
[tex]\begin{aligned}& N(t)=N_0\left(\frac{1}{2}\right)^{\frac{t}{1 / i 2}} \\& N(t)=N_0 2^{-\frac{1}{t_1 / 2}} \\& N(t)=N_0 e^{-\frac{t}{t}} \\& N(t)=N_0 e^{-\lambda t}\end{aligned}[/tex]
where:
N0 is the initial quantity of the substance that will decay.
N(t) is the quantity that still remains and has not yet decayed after a time t
t½ is the half-life of the decaying quantity,
τ is a positive number called the mean lifetime of the decaying quantity,
λ is a positive number called the decay constant of the decaying quantity.
Starting with a 125g sample of U-235.
U-235 has a half-life of 704 million years, which means that every 704 million years, half of the remaining U-235 will have decayed. After three half-lives or 3 x 704 million years = 2112 million years, 1/2 x 1/2 x 1/2 = 1/8 of the original sample will remain.
So, if you started with a 125g sample of U-235, after 2100 million years, 125g x 1/8 = 15.625g would remain.
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What's bruise formed by collection of blood at the puncture site
A hematoma was a swelled or elevated region at the site of venipuncture brought on by blood seeping into the tissues.
After a blood draw, bruises are a common occurrence. A bruise often goes away within a few days. But occasionally a bump can serve as a warning indicator. When a blood artery is injured, blood leaks into the tissue beneath your skin, resulting in a bruise. A hematoma was a swelled or elevated region at the site of venipuncture brought on by blood seeping into the tissues. Blood clots typically result in a coloration that is darker than surrounding skin. The medical name for bruises is ecchymosis. Bruises resemble a dark mark on your skin.
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What is the main function of the circulatory cardiovascular system?
The circulatory system eliminates waste items like carbon dioxide and delivers nutrition, hormones, and oxygen to cells.
Your heart and blood arteries make up your circulatory system, commonly referred to as your cardiovascular system. It functions to carry oxygen and other nutrients to all of your body's organs and tissues. Carbon dioxide and other waste materials are also removed. You need a healthy circulatory system for both your physical and mental well-being. Continue reading to learn more about the circulatory system, how it works, and what you can do to maintain the health of your heart and blood vessels.
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The fish in a certain population average 10 millimeters in length. Imagine that a population of predatory birds arrives in the area, but they cannot eat fish longer than 15 millimeters. After many, if the fish average 14 millimeters in length, what probably happened?
A. There was a stabilizing selection for fish length.
B. There was disruptive selection for fish length.
C. The fish and the predator coevolved.
D. The presence of the predator causd mutation for larger fish to occur.
E. There was directional selection for fish length.
There was directional selection for fish length was happened. Directional selection occurs when individuals with traits on one side of the mean survive or reproduce more than those on the other. option e)
What is directional selection give an example?Directional selection is a type of natural selection in which extreme variants of a trait are favored over intermediate variants. This results in the shifting of the population's trait distribution in the direction of the extreme variants. An example of directional selection is the evolution of the finches in the Galapagos Islands, in which the finches with longer beaks were able to feed on larger seeds, giving them an advantage in survival and reproduction.
The presence of the predator caused the fish to evolve longer lengths in order to avoid being eaten. This resulted in the fish population average increasing from 10 millimeters to 14 millimeters. Directional selection is the process of natural selection that occurs when a trait is favored and the population average shifts in the direction of that trait.
Therefore, option (e) There was directional selection for fish length is the correct answer.
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how are sister chromatids connected to each other?
The centromere, a constrictive area of the chromosome, is where the two "sister" chromatids are linked.Spindle fibers that are attached to the centromere pull their sister chromatids to a opposing sides of the cell during cell division.
How are sister chromatids able to remain paired?The sister chromosomes are held together by a protein complex called cohesin that forms a ring around the DNA and is conserved from single-celled creatures to humans.
How do sister chromatids develop?When identical chromatids are fused at the centromere, sister chromatids are created.Twin sister chromatids are all in contact with one another at the centromere, which is a constrictive area.
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The chemical digestion of proteins begins in the:
a. stomach
b. small intestine
c. mouth
d. pancreas
The chemical digestion of proteins begins in the stomach. (option a) Stomach acid and the enzyme pepsin break down proteins into smaller peptides to digest.
This can then be further broken down into individual amino acids by other digestive enzymes in the small intestine.
The process of protein digestion begins in the stomach, where proteins are exposed to gastric juice, which contains hydrochloric acid and the enzyme pepsin. Pepsin acts on the proteins, breaking them down into smaller peptides. The acidic environment of the stomach also helps to denature the proteins
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the breaking apart of an intervertebral disk resulting in a bulge that can put pressure on spinal nerve roots are called?
The rubbery discs between both the vertebrae of the spine are made up of a softer inside (nucleus) and a more robust outer (annulus). When a section of a nuclei pushes through a tear in the annulus.
What results in a disc bulging?As they get older, discs start to show wear and tear. The cartilage of discs stiffens and dehydrates over time. These modifications can lead the outer layer of the disc to protrude rather uniformly the all way around its circumference, giving it the appearance of a hamburger with a bun that is too big.
What does a spine bulge mean?Any part of the spine can develop a herniated disc, but the lower back is where it most frequently does. It is also known as a protruding, bulging, or ruptured disc. It is among the most typical causes of sciatica, leg discomfort, and lower back pain.
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A cell with a large volume will have a more difficult time doing what?
A cell with a large volume will have a more difficult time efficiently transporting materials throughout its interior.
The transport of molecules such as nutrients, waste products, and signaling molecules is crucial for the proper functioning of a cell. In a cell with a large volume, diffusion of these molecules from one side of the cell to the other can take longer, and this can limit the rate of cellular processes. Additionally, the ratio of surface area to volume in a cell decreases as the cell increases in size, which can make it more difficult for the cell to efficiently exchange materials with its environment.
One way that cells cope with this challenge is by increasing their surface area through the development of specialized structures such as microvilli, which are finger-like projections on the surface of some cells. Another way is by dividing into smaller daughter cells, as occurs during cell division. However, there is a limit to how large a cell can grow and still function efficiently, and this limit varies depending on the specific cell type and environmental conditions.
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During oxidative phosphorylation, which answer choice best describes how electrons move?
Therefore, response option (A), which describes the mechanism by which electrons flow down an electron transport chain, resulting in the synthesis of ATP from ADP.
During oxidative phosphorylation, how do electrons move?Protons are pushed out of the matrix and into the intermembrane space as a result of the electrons moving through the electron transport chain. The electrons eventually reach oxygen, which reacts with protons to create water.
Where are the electron transport proteins for oxidative phosphorylation found in the cell?The electron transport chain, commonly referred to as the oxidative phosphorylation process, is made up of four protein complexes that work together to combine redox events to create an electrochemical gradient that leads to the synthesis of ATP.
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which two of these terms are better applied to eukaryotic flagella than to bacterial flagella?
The terms "microtubules" and "undulipodia" are better applied to eukaryotic flagella than to bacterial flagella.So option a and b are correct.
Eukaryotic flagella are complex organelles composed of a bundle of microtubules arranged in a characteristic 9+2 pattern, which provides support and rigidity to the structure. In addition, the movement of eukaryotic flagella is generated by the sliding of microtubules against each other, powered by dynein motor proteins. This mechanism is quite different from that of bacterial flagella, which rotate like propellers and are powered by a rotary motor at the base.
The term "undulipodia" refers to the undulating, wave-like motion of eukaryotic flagella, which is generated by the coordinated sliding of microtubules. Bacterial flagella, on the other hand, move in a more linear, propeller-like fashion, without undulations.
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Complete question:
which two of these terms are better applied to eukaryotic flagella than to bacterial flagella?
a.undulipodia
b.microtubules
c.nucleus
d.cilia
When is fat used as a more efficient fuel?
The energy source that predominates at low power outputs ( 40% VO2max) and delivers significant amounts of energy during intermediate intensity exercise (40-65% VO2max) is fat, which is intended to be a helper fuel during aerobic activity.
Triglycerides, also referred to as triple esters of glycerol, are the primary component of vegetable oils and animal fatty tissue. The phrase frequently excludes oils and just refers to these triglycerides. Moreover, the phrase can be used more broadly to describe any elemental component of biology that is soluble in non-polar solvents but insoluble in water and contains carbon, hydrogen, or oxygen. This phrase can also be used to refer to a number of less well-known nutrients found in a typical human diet, including mono- and diglycerides, phospholipids (like lecithin), sterols (like cholesterol), waxes (like beeswax), and free fatty acids.
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the apical plasma membranes of simple squamous epithelial cells are often folded into microvilli, which increases their surface area for absorption. True or False
Ribosomal RNA is encoded by portions of the DNA on some chromosomes. The nucleolus is a darkly pigmented region inside the nucleus.
Anatomy of a nucleus?The membrane-enclosed nucleus is just where RNA is synthesised from the chromosomal DNA.
With a microscope, it is easily pigmented and visible. It serves as the hub for all of a cell's operations.
How do chromosomes work?There are typically 23 pairs of chromosomes in the nucleus. Each cell's nucleus contains the chromosome, which is packed into thread-like filaments.
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Fill in the blank: The ribosome ______BLANK subunit has _______BLANK binding sites for tRNA molecules.
Question 1 choices
Choice A., large; two
Choice B., small; two
Choice C., large; three , [Your answer, correct]
Choice D., small; three
Choice E., large; four
The ribosome large sub unit has three binding sites for tRNA molecules.
The correct answer is option C.
A ribosome binding point, or ribosomal list point( RBS), is a sequence of nucleotides upstream of the launch codon of an mRNA paraphrase that's responsible for the reclamation of a ribosome during the inauguration of restatement. substantially, RBS refers to bacterial sequences, although internal ribosome entry spots( IRES) have been described in mRNAs of eukaryotic cells or contagions that infect eukaryotes. Ribosome reclamation in eukaryotes is generally intermediated by the 5' cap present on eukaryotic mRNAs.
The RBS in prokaryotes is a region upstream of the launch codon. This region of the mRNA has the agreement 5'- AGGAGG- 3', also called the Shine- Dalgarno( SD) sequence. The reciprocal sequence( CCUCCU), called theanti-Shine-Dalgarno( ASD) is contained in the 3 ’ end of the 16S region of the lower( 30S) ribosomal subunit. Upon encountering the Shine- Dalgarno sequence, the ASD of the ribosome base dyads with it, after which restatement is initiated.
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Most of the growth of a plant body is the result of a. cell differentiation. b. morphogenesis. c. cell division. d.cell elongation.
The cause of the majority of a plant's growth. cell differentiation, letter A. morphogenesis is (B). cell division (C). (D) cell lengthening.
What kind of growth development is that?
Growth is a rise in size, much like how a seedling develops into a full-grown tree. There are other types of growth as well, such as the development of your sister's personality since she began daily meditation.
What does life's progress growth?
Growth is the constant expansion of an individual's size through time. It could also be described as one of a living thing's traits. The term "biological growth" refers to development that occurs throughout time in biology. The growth of an organism may continue throughout its existence or stop when that species reaches sexual maturity.
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Is phospholipid bilayer the same as cell membrane?
The cell membrane is composed of two layers of phospholipid molecules, but also contains other macromolecules such as membrane proteins, and carbohydrates.
The lipid bilayer (also known as the phospholipid bilayer) is a thin polar membrane composed of two layers of lipid molecules. These membranes are flat sheets that surround all cells in a continuous barrier. Almost all animals and many viruses have lipid bilayer cell membranes, as do the nuclear membrane encircling the cell nucleus and the membranes of the cell's membrane-bound organelles.
The lipid bilayer acts as a barrier, keeping ions, proteins, and other molecules where they are needed and preventing them from diffusing into locations they should not be.
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"Which statement is true?
A. There are more neurons than glia in the brain.
B. Neurons are all the same shape and size.
C. Some neurons have no axons.
D. Glia are not necessary for normal brain functioning."
Some neurons have no axons. This statement is true. Here option C is the correct answer.
Neurons are the primary cells in the nervous system that are responsible for transmitting information through electrical and chemical signals. They are characterized by a cell body, dendrites, and an axon. Dendrites receive signals from other neurons or sensory cells, while the axon transmits signals to other neurons, muscles, or glands.
However, not all neurons have an axon. Some neurons, called interneurons or local circuit neurons, have dendrites that receive signals and transmit signals to other neurons within a local circuit but do not have an axon that projects to distant parts of the nervous system. Other types of neurons, such as sensory neurons, may have a very short axon that does not project far from the cell body.
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mutations that are harmful to cells occur more frequently than those that benefit cells. T/F
The given statement ''mutations that are harmful to cells occur more frequently than those that benefit cells'' is true because the genetic code is highly conserved, meaning that any changes to it have the potential to disrupt normal cellular functions.
Most mutations that occur are either neutral (having no effect on the organism) or harmful (causing negative effects on the organism). Beneficial mutations, which confer a selective advantage, are relatively rare. This is because the genetic code is highly conserved and mutations that alter it are more likely to disrupt normal cellular functions than to improve them. However, over long periods of time and under certain circumstances, beneficial mutations can accumulate and lead to evolutionary changes.
For example, mutations can disrupt the normal function of genes, leading to abnormal cellular processes and the development of diseases such as cancer. Mutations can also cause structural changes in proteins, altering their ability to carry out their normal functions. Harmful mutations can occur spontaneously during DNA replication, or they can be caused by environmental factors such as radiation, chemicals, or viruses.
Overall, Mutations that are harmful to cells occur more frequently than those that benefit cells.
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Characteristics used to describe a substance are called
Answer:physical properties
Explanation:
why muscles are not likely to tear from their bones.
Heart muscles, smooth muscles, and cardiac muscles are not bone-attached. Keep in mind that these muscles are controlled involuntarily. Hollow organs including blood arteries, the digestive system, the bladder, and the uterus may contract because of smooth muscle.
How exactly do muscles defend bones?Skeletal muscle protects the skeletal system from external impacts by absorbing and transferring the energy of mechanical stress in time and space. This function of skeletal muscle is one of the least understood.
Skeletal muscles are joined to the bones by connective tissues like ligaments or bone in the muscular system. All muscles have two or more points of attachment.
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What role do valves play in returning blood to the heart?
By opening when blood flows towards the heart or closing when blood flow backward, valves aid in the return the blood to the heart. The movement of blood towards the heart is significantly aided the deep veins.
What heart valve is the most crucial?Before leaving the heart and travelling through the remainder of the body, oxygen-rich blood must pass through one more valve, the aortic valve. Blood cannot return via the valve to a left ventricle.
Which are the 4 heart valves and what do they do?Blood is moved by two of the valve, the mitral and tricuspid valves, from the heart's upper chambers (the atria) to its lower chambers (the ventricles). The pulmonary and aortic valves, the other two valves, channel blood through the ventricles to the lungs or the rest of the body.
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