MULTIPLE CHOICE QUESTION
Which of the following are components of most
viruses? Select all that apply.

A. Lipid envelope

B. Cell wall

C. Attachment proteins or
envelope proteins (sometimes
also called virus spikes)

D. protein capsid which contains.
the genetic material.

E. DNA or RNA as genetic
material

Concentric contractions occur when the muscle produces increasing tension as it shortens. Thus, the correct option will be A.

Concentric contraction is the shortening of the muscles while the tension remains the same. The tension is produced when the fibers of the muscles pull together, which results in shortening the muscle. An example of a concentric contraction is the upward motion in a bicep curl, and it is also referred to as a positive contraction. This means that the muscle is contracting while shortening.

When the muscle shortens, the distance between the muscle’s origin and insertion points decreases. This creates a movement around a joint, which is known as concentric motion. This type of contraction also occurs when you lift weights. Lifting weights involves the shortening of muscles around the joints to raise the weight. When you perform bicep curls, the muscles in the bicep shorten, allowing you to lift the weight.  

Learn more about Concentric contractions here:

https://brainly.com/question/1526538

#SPJ11

In your experiments with a star changer, you must have observed the relative brightness which is: directly related to the diameter of the lens.

The diameter of the lens, in turn, is directly proportional to the intensity of light that the lens captures. The relative brightness is also related to the surface area of the lens. The surface area, as we know, increases with the square of the diameter of the lens.

Therefore, if the diameter of the lens is doubled, the surface area will increase fourfold, making the image brighter. As a result, we can say that the brightness of the image observed in a star changer is directly proportional to the diameter of the lens, which is dependent on the surface area of the lens.

A bigger lens will be able to capture more light, resulting in a brighter image. Another way to increase the brightness of the image is to use a lens with a lower focal length. As the focal length of the lens is decreased, the image is magnified more, making it appear brighter.

However, this method comes with a downside. As the focal length decreases, the image's clarity decreases as well. Therefore, a balance between the diameter of the lens and the focal length must be maintained to get a bright and clear image of the star.

To know more about relative brightness refer here:

https://brainly.com/question/7966158#

#SPJ11

C basing models on an incomplete or inaccurate observation is a limitation of using models in science.

Limitation is a restriction or constraint placed on a person, activity, or object. It can be physical, legal, or even psychological. In the legal context, limitations are often imposed by laws, regulations, court orders, or contracts. Physical limitations may include physical barriers, geographic boundaries, or natural obstacles. Psychological limitations may involve beliefs, attitudes, or fears that prevent a person from taking certain actions or achieving a desired outcome.

This can lead to inaccurate and unreliable results and conclusions, which can cause confusion and misunderstanding between scientists. Additionally, models can be difficult to modify and update as more accurate information becomes available. As such, models need to be updated regularly to ensure accuracy and to remain relevant.

To learn more about limitation
https://brainly.com/question/30237531
#SPJ1

Chlorophyll a contains 6 oxygen (O) atoms.Chlorophyll b contains 6 oxygen (O) atoms.Beta Carotene contains 0 oxygen (O) atoms. Xanthophyll contains 4 oxygen (O) atoms.

Chlorophyll is the molecule responsible for photosynthesis in plants, algae, and cyanobacteria. It is a vital pigment that helps in converting light energy into chemical energy. Chlorophyll is composed of a porphyrin ring and a phytol chain. The porphyrin ring contains nitrogen, magnesium, and oxygen.

Chlorophyll a has a methyl group at the 3-position of the ring and a formyl group at the 7-position of the ring. Chlorophyll b differs from chlorophyll a in having a formyl group at the 8-position of the ring and a methyl group at the 3-position of the ring.

Beta Carotene is a type of carotenoid that does not contain any oxygen atoms. It is an organic compound that is made up of isoprene units. Beta Carotene is a yellow-orange pigment that is used as a precursor of vitamin A in animals.Xanthophyll is another type of carotenoid that contains four oxygen atoms. It is a yellow pigment that is found in leaves and other plant parts. Xanthophyll is similar to beta-carotene, but it contains oxygen atoms.

More on chlorophyll: https://brainly.com/question/1427396

#SPJ11

To ensure that these processes are properly regulated, the endocrine system employs a feedback mechanism to regulate hormone levels.

Feedback regulation is the process by which hormone levels are regulated in the endocrine system. Hormones are chemical messengers that travel throughout the body to regulate various physiological processes. This feedback mechanism operates through a series of feedback loops that monitor hormone levels in the blood and adjust hormone secretion accordingly.

Hormones are chemical messengers that are produced by the endocrine glands and secreted into the bloodstream. These hormones travel to target cells in the body, where they bind to specific receptor proteins on the surface of the cell. The binding of a hormone to its receptor triggers a series of signaling pathways within the cell that ultimately lead to changes in gene expression and other cellular processes.

Feedback regulation is critical to maintaining proper hormone levels in the body. When hormone levels become too high or too low, the feedback mechanism responds by adjusting hormone secretion to restore balance. This ensures that the body's physiological processes remain properly regulated and functioning efficiently.

To know more about endocrine system:

https://brainly.com/question/29526276

#SPJ11

Carbohydrates are the sugars, starches, and fibers present in fruits, grains, vegetables, and milk products. These are one of the main sources of energy for the body. Carbohydrates are essential macronutrients that have a wide range of biological and physiological benefits for the body, including supplying energy: Carbohydrates supply the body with glucose, which is then converted into energy in the form of ATP. This energy is used by the body for various purposes including physical activity, metabolic processes, and internal functions such as circulation and breathing. Preventing the breakdown of protein: If insufficient carbohydrate is available, the body can use protein for energy, resulting in the breakdown of muscle tissue.Assisting in metabolic functions: Carbohydrates help to regulate metabolic functions such as the metabolism of fats and proteins. They also play a role in insulin regulation and cholesterol metabolism.

Carbohydrates are the body's primary energy source.

For more information regarding this topic, you can click the below link

https://brainly.com/question/336775

#SPJ11

Osteoporosis is the condition for which obesity-related risk factors are NOT present. Obesity can raise the risk of a number of illnesses, such as hypertension, abnormal blood lipids, and sleep apnea.

According to a recent study, obesity is not associated with severe acute respiratory diseases, including the flu, in either children or adults, despite the fact that it has previously been thought to be a risk factor for more severe episodes of the flu.

Both adults and children are affected by obesity. Eating habits, physical activity levels, and sleep schedules are just a few of the many variables that might lead to excessive weight gain. Genetics, social factors of health, and using specific medications all have an impact.

To know more about Osteoporosis visit:-

https://brainly.com/question/7246059

#SPJ1

Only for plasmids: Can transfer genes for antibiotic resistance, but only on chromosomes: Contains genes necessary for survival and Both have the following traits: only replicates during prokaryotic fission

Prokaryotes have only one chromosome, which are typically circular DNA molecules that hold their whole genomes. The genomes of eukaryotes, in contrast, are made up of several chromosomes, each carrying a linear DNA molecule.

Little numbers of non-essential genes are carried by plasmids, which are copied separately from chromosomes inside cells. They can propagate genes that are helpful for survival to other prokaryotes in the population.

To know more about chromosomes visit:-

https://brainly.com/question/30764627

#SPJ1

Answer: myelinated

Explanation:

Saltatory conduction occurs only on myelinated axons.

Saltatory conduction occurs in myelinated axons. The myelin sheath on these axons promotes faster signal propagation by allowing action potentials to 'jump' from one node of Ranvier to the next.

Saltatory conduction occurs in myelinated axons. Myelinated axons are axons that are covered by a fatty substance known as myelin. This myelin sheath insulates the axon and increases the speed at which electrical impulses, or action potentials, are transmitted along the axon. During saltatory conduction, the action potential 'jumps' from one node of Ranvier to the next. These nodes are the small gaps in the myelin sheath along the axon. Compared to unmyelinated axons, where the action potential propagates in a continuous wave, the 'jumping' action in myelinated axons leads to faster signal propagation.

https://brainly.com/question/12959628

#SPJ6

The drug that blocks the DNA replicating enzyme affects the S-phase of the cell cycle, during which DNA replication occurs.

In actively dividing human cells, the cell cycle progresses through several stages, including interphase, mitosis, and cytokinesis. The S-phase is a critical stage during interphase, in which the cell's DNA is replicated in preparation for cell division. Blocking the DNA replicating enzyme would halt DNA synthesis and prevent the cell from proceeding to the next stage of the cell cycle, resulting in cell cycle arrest. This technique is often used in research to study the effects of blocking DNA replication on cellular processes and to investigate potential treatments for cancer and other diseases.

To know more about enzyme click here:

brainly.com/question/14953274

#SPJ4

Stomata are the mouth-shaped openings in the epidermis of plants. These tiny pores are surrounded by two specialized guard cells that control the opening and closing of the stomata.

The guard cells are responsible for regulating the exchange of gases and water vapor between the plant and its environment. When the stomata are open, carbon dioxide can enter the plant and oxygen and water vapor can exit. This process, known as transpiration, is essential for plant growth and survival. Stomata are typically found on the leaves of plants, although they can also be found on stems and other parts of the plant. The number and distribution of stomata on a plant can vary depending on the species, environmental conditions, and other factors. In general, plants that live in dry or arid environments tend to have fewer stomata, while those that live in wetter environments tend to have more. Additionally, some plants have specialized stomata that are adapted to specific environmental conditions. For example, certain plants that live in saline environments have evolved stomata that are able to exclude salt from entering the plant. Overall, stomata play a crucial role in the life of plants, allowing them to breathe and absorb the nutrients they need to grow and thrive.

To learn more about Stomata :

https://brainly.com/question/19393475

#SPJ11

RNA primers are not required for transcription, they are required for DNA replication. In transcription, the RNA polymerase initiates RNA synthesis without an RNA primer.

RNA stands for ribonucleic acid. It is a type of nucleic acid that is involved in various biological processes in cells, including protein synthesis, gene regulation, and catalysis of biochemical reactions.

RNA is similar to DNA in that it is made up of nucleotides, which consist of a sugar molecule, a phosphate group, and a nitrogenous base. However, RNA differs from DNA in several ways.RNA also uses the sugar ribose, while DNA uses deoxyribose. Additionally, RNA uses the base uracil instead of thymine, which is found in DNA.

RNA carries the genetic information from DNA to the ribosomes, where it is used to synthesize proteins..

To know more about RNA visit :

https://brainly.com/question/20914096

#SPJ1

Prophase I is an important stage of meiosis I because it leads to the creation of genetically diverse haploid cells.

The first phase of meiosis I, the process of cell division that results in haploid cells, is known as prophase I. As a result of prophase I, the following things happen:

To know more about Prophase I

brainly.com/question/30415028

#SPJ4

4, 7, 6, 1, 2, 3, 5 is the correct sequence of generation of an action potential . These are the main steps involved in the generation of an action potential

The steps involved in the generation of an action potential are as follows:

4. A graded depolarization brings an area of the excitable membrane to threshold .

7. Sodium channel activation occurs: Sodium channel activation occurs, and sodium ions enter the cell, causing depolarization.

6. Sodium channels are inactivated after depolarization.

1. Voltage-regulated potassium channels open: Voltage-regulated potassium channels open, and potassium moves out of the cell, initiating repolarization.

2. Sodium channels regain their normal properties: After repolarization, sodium channels regain their normal properties.

3. Sodium ions enter the cell adn depolarization occurs.

5. Temporary hyperpolarization occurs: A temporary hyperpolarization occurs after repolarization.

Therefore, these are the main steps in the generation of action potential. Thus the correct sequence is 4, 7, 6, 1, 2, 3, 5.

To know ore about Action potential please visit:

https://brainly.com/question/22935372

#SPJ11

The following are the main steps in the generation of an action potential:

1. Voltage-regulated potassium channels open and potassium moves out of the cell, initiating repolarization.

2. Sodium channels regain their normal properties.

3. Sodium ions enter the cell adn depolarization occurs.

4. A graded depolarization brings an are of an excitable membrane to threshold.

5. A temporary hyperpolarization occurs.

6. Sodium channels are inactivated.

7. Sodium channel activation occurs.

DNA is a polymer of nucleotides, which is composed of a ribose, phosphate, and nucleic acid. The 3'-OH (hydroxyl) characteristic of the ribose is required for termination of a DNA strand in DNA sequencing.

What is DNA? Deoxyribonucleic acid or DNA is a genetic material present in all living things. DNA contains the instructions that are required to develop and sustain life. DNA contains nucleotides, which are the building blocks of DNA. A nucleotide consists of a deoxyribose sugar molecule, a phosphate molecule, and a nucleic acid molecule. The nitrogenous bases are the nucleic acid molecules that differ between the nucleotides.

A nucleotide is a phosphate molecule that is linked to the 3′ hydroxyl (OH) group of the deoxyribose sugar of one nucleotide and the 5′ hydroxyl (OH) group of the deoxyribose sugar of the next nucleotide. Because DNA is constructed of nucleotides that are linked through their phosphate and hydroxyl groups, sequencing of DNA involves breaking the chain and identifying each of the components to determine the order of the nucleotides that make up the sequence of DNA. Sequencing of DNA is a vital tool for the study of genetics, including the determination of the DNA sequence of an entire genome of an organism. Therefore, the 3'-OH (hydroxyl) characteristic of the ribose is required for termination of a DNA strand in DNA sequencing.

"DNA sequencing", https://brainly.com/question/31134639

#SPJ11

A bacterium producing a positive Voges-Proskauer (VP) test indicates the presence of acetoin, a neutral end product of glucose fermentation.

The VP test is used to differentiate between bacteria that produce acidic end products of glucose fermentation (negative VP test) and those that produce neutral or slightly alkaline end products, such as acetoin (positive VP test). The test involves adding a reagent containing alpha-naphthol and potassium hydroxide to a bacterial culture that has been grown in a medium containing glucose.

If the bacterium produces acetoin, the alpha-naphthol reacts with it to form a red-colored complex. This test is often used in the identification of members of the Enterobacteriaceae family, such as Escherichia coli and Enterobacter aerogenes, which are known to produce acetoin.

To learn more about bacterium refer to

brainly.com/question/30500074

#SPJ4

Answer:

Lysosome

Explanation:

A lysosome is a membrane-bound cell organellethat contains digestive enzymes.

Lysosome are involved with various cell processes

hope it helpful ^_^

The double membrane that encloses the nucleus is called the nuclear envelope.

The nuclear envelope is a double-layered membrane that encloses the nucleus. It is made up of two concentric membranes and is supported by an internal cytoskeletal network of intermediate filaments known as the nuclear lamina.

It is made up of two membranes, an inner membrane that surrounds the nucleoplasm and an outer membrane that is contiguous with the endoplasmic reticulum membrane.

The two membranes are separated by a perinuclear space, which is approximately 10-50 nm thick, and are joined by nuclear pores that allow the selective movement of molecules in and out of the nucleus.

Nuclear pores are large protein complexes that regulate the movement of molecules in and out of the nucleus, such as RNA and proteins.

For such more question on membrane:

https://brainly.com/question/1768729

#SPJ11

Fossils is the name which is given to the preserved remains or traces of dead organisms therefore the correct option is A.

Fossils are the remains or traces of ancient organisms, such as plants and animals, that have been preserved in rocks or other materials. They're important for understanding the history of life on Earth. Fossils give information about the ancient organisms, and the  surroundings in which they lived.

They also  give  substantiation for evolutionary  connections between organisms, as well as  suggestions to ancient  surroundings. Studying Fossils gives us  sapience into the  history and helps us to more understand present- day life.

Hence the correct option is A.

To know more about Fossils visit:

https://brainly.com/question/2288828

#SPJ4

The assertion is untrue. The protein repressor undergoes a conformational shift when lactose attaches to it, preventing it from binding to the lac operator.

The lac repressor is rendered inactive by lactose, which also stops the repressor protein from attaching to the lac operator. Transcription can continue after the repressor has been deactivated. As a result, for the lac operon to effectively transcribe, glucose must be missing and lactose must be present.

A repressor is prevented from binding to the operator by an inducer (allolactose or an analogue), which releases the repression and permits transcription of the lac operon.

To know more about lactose visit:-

https://brainly.com/question/13061505

#SPJ1

The types of daughter cells produced during meiosis are Genetically distinct due to crossing over.

Daughter cells are the cells that divide from the mother cell during cell division. In somatic cells, the process of mitosis results in the production of two daughter cells, whereas the process of meiosis results in the production of four daughter cells in germ cells.

Meiosis is a kind of cell division that results in the production of four gamete cells and a 50% reduction in the number of chromosomes in the parent cell. To develop egg and sperm cells for sexual reproduction, this procedure is necessary. The number of chromosomes is restored in the progeny when the sperm and egg combine to create a single cell during reproduction.

The original cell's cytoplasm is now split into two daughter cells as the cell goes through a process known as cytokinesis. Only one set of chromosomes, or half as many as the parent cell's total number, are present in each haploid daughter cell.

Learn more about meiosis :

https://brainly.com/question/29537686

#SPJ4

Answer: oxygenated blood to the lungs 

A bacterium or other molecule is taken up by phagocytosis directed to lysosomes for debasement. Phagocytes are capable of ingesting not only apoptotic cells but also microbial pathogens.

The process of phagocytosis involves the recognition and ingestion of particles larger than 0.5 m into a phagosome, a vesicle derived from the plasma membrane.

The recognition and ingestion of microbial pathogens larger than 0.5 m into a phagosome-derived vesicle mark the beginning of phagocytosis. Several receptors that recognize specific microorganism-associated molecular patterns enable this recognition.

Phagocytosis is a process that phagocytic cells use to identify invading microbes and kill them once they have entered the body. It is a receptor-driven process that dates back to evolution. The bacterial infection's survival depends on the expression of the phagocytosis receptor Eater, which is only found in Drosophila phagocytes.

To learn more about phagocytes here

https://brainly.com/question/16185213

#SPJ4

The farming of fish such as salmon at aquaculture facilities poses a threat to marine ecosystems because "it provides a healthy and inexpensive source of protein."

It is possible to avoid the issues which pose a threat to marine ecosystems and aquaculture due to salmon fish by being responsible and minimizing the environmental impact of salmon farming while reaping the benefits of this resource.

Despite this, some of the challenges related to farming salmon include the following Salmon farming benefits include the following it provides a healthy and inexpensive source of protein. Salmon farming generates employment. It decreases the pressure on wild fish populations. It reduces the use of marine resources such as oil. It helps to balance the global seafood trade.

Learn more about Aquaculture here:

https://brainly.com/question/275198

#SPJ11

Genomics is the answer.

The cells under a microscope can be identified as red blood cells (erythrocytes) due to their characteristic. The cells under a microscope can be identified as red blood cells (erythrocytes) due to the fact that these cells do not contain a nucleus, the cells are flattened, and their central part is usually depressed.

Like all cells in the human body, red blood cells are surrounded by a thin, flexible cell membrane. Hemoglobin, a protein that binds to oxygen, is found in the cell and is responsible for the cells' red color. Red blood cells are highly versatile cells, making it easy for them to squeeze through tiny capillaries, a function made possible by their small size and flexibility. These cells transport oxygen from the lungs to the body's tissues and release carbon dioxide from the tissues to the lungs.

Learn more about red blood: https://brainly.com/question/87588

#SPJ11

These constraints may include financial resources, location, potential negative impact on other wildlife in the area, the feasibility of managing the species in the wild, the need for confinement during management, and safety concerns.

Given that wildlife management initiatives can be costly, financial resources must be taken into account. The price of supplies, labor, and veterinary care can all be included in the cost of managing wildlife. Location can also affect how much it costs to manage a species because it may be harder to get to some places.

The project's potential effects on other wildlife must also be taken into account. Other species in the area may suffer unintended consequences from the management of one species. For instance, the eradication of a predator species might cause its prey to become overpopulated.

Finally, safety issues must also be considered. The management of wildlife can be dangerous, especially if the species is potentially dangerous to humans. To ensure the safety of both people and wildlife in such circumstances, the project might need to be restricted to a more controlled environment.

Learn more about wildlife

brainly.com/question/13094718

#SPJ4

The life cycle of an average-sized star like the sun starts with the collapse of a cloud of gas and dust under the force of gravity.

As the cloud collapses, it becomes more massive and heats up, eventually reaching a temperature and density that allow nuclear fusion reactions to occur in its core. These fusion reactions convert hydrogen into helium, releasing energy in the form of light and heat.

This phase called the main sequence, can last for billions of years, during which the star is stable. In contrast, high-mass stars have a much shorter lifespan and a more explosive end. Due to their high mass, they burn through their fuel at a much faster rate, causing them to evolve more quickly.

They also undergo a series of nuclear fusion reactions, creating heavier elements in their cores. Eventually, these stars will run out of fuel, and the core will collapse. This collapse triggers a supernova explosion that can be more than 10 times brighter than an average-sized star. After the explosion, the core may collapse further, forming a black hole or a neutron star.

To learn more about life cycle

https://brainly.com/question/12600270

#SPJ4