Viruses that utilize reverse transcriptase belong to the virus families
A) Retroviridae and Picornaviridae.
B) Herpesviridae and Retroviridae.
C) Hepadnaviridae and Retroviridae.
D) Herpesviridae and Poxviridae.
E) Rhabdoviridae and Herpesviridae.

Answers

Answer 1

The correct option is C, Viruses that utilize reverse transcriptase belong to the virus families Hepadnaviridae and Retroviridae.

Viruses are tiny infectious agents that can only replicate inside a host cell. They consist of genetic material, either DNA or RNA, surrounded by a protein coat called a capsid. Some viruses also have an outer envelope made of lipids.

Viruses are not considered living organisms because they cannot carry out metabolic processes on their own and rely on host cells for reproduction. Once inside a host cell, the virus hijacks the cell's machinery and uses it to make copies of itself. This can lead to cell damage and the release of new viruses, which can go on to infect other cells.

To learn more about Viruses visit here:

brainly.com/question/30972422

#SPJ4


Related Questions

Classify each description as associated with either positive or negative selection. TCR must recognize MHC T-lymphocyte survival dependent on not recognizing self-antigen T-lymphocyte survival dependent on ability to bind MHC Thymic epithelial cells present MHC to T-lymphocytes TCR must not bind self- antigen Cells develop self-tolerance Dendritic cells present MHC with self-antigen to T-lymphocytes Positive Selection Negative Selection TCR must recognize MHC TCR must not bind self- antigen Thymic epithelial cells present MHC to T-lymphocytes Dendritic cells present MHC with self-antigen to T-lymphocytes T-lymphocyte survival dependent on ability to bind MHC T-lymphocyte survival dependent on not recognizing self-antigen Cells develop self-tolerance

Answers

Positive Selection:

TCR must recognize MHCThymic epithelial cells present MHC to T-lymphocytesT-lymphocyte survival dependent on ability to bind MHC

Negative Selection:

TCR must not bind self- antigenDendritic cells present MHC with self-antigen to T-lymphocytesT-lymphocyte survival dependent on not recognizing self-antigenCells develop self-tolerance

What should you know about TCR must recognize MHC?

T-cell receptor (TCR) must recognize major histocompatibility complex (MHC) molecules in order to initiate an immune response. MHC molecules are found on the surface of cells and they bind to and present foreign peptides to T-cells, which are then activated to recognize and eliminate the foreign substance. MHC molecules come in two types, MHC class I and MHC class II, which present antigens to CD8+ T-cells and CD4+ T-cells, respectively. The specificity of TCR for MHC molecules is essential for the proper functioning of the immune system, as it enables T-cells to recognize and respond to a wide range of foreign pathogens while ignoring healthy cells.

Find more exercises on TCR;

https://brainly.com/question/29727609

#SPJ1

Question.
What is an adaptation?


Responses:

1: A change that helps a species survive.

2: A change that makes a species become extinct.

3: A change that prevents a species from surviving.

4: A change that makes a species prettier to look at.

Answers

the correct answer is A. It is the change that helps a species survive.

for animals to survive they have to adapt to their environments and sometimes they have to make changes as their environments change constantly around them so the answer would be 1: A change that helps a species survive. sorry if it doesn't make sense i try my best to explain

Conversion of G3P to RuBP energy and it is coupled to O requires; conversion of ATP to ADP + Pi releases; conversion of NADPH to NADP+ releases; conversion of ADP + Pi to ATP requires; conversion of NADP+ to NADPH Question 3 (1 point) Which feature is shared by both chloroplasts and mitochondria? Electrons flow from NAD(P)H to O2. They both have an outer membrane, and inner membrane, and a matrix. They both have proton gradient across their inner membrane. A proton gradient is counled to ATP synthesis What would happen to the light reactions if the Calvin cycle stopped conver NADPH to NADP+? The light reactions would speed up because plants need the Calvin cycle tu survive and increasing the light reactions increases the Calvin cycle. The light reactions would stop because NADP+ is needed to accept electron from the light reactions. The light reactions would continue because they make NADPH for the Calvin cycle but do not depend on the Calvin cycle for anything. The light reactions would continue because all they require is light and water to make O2 and ATP. Next Page Page 2 of 3 25 esc FS F2 80 3 999 54 ES $ & 1 2 3 4 % 5 6 7 Q tab W E R T Y A S D F cans lock G Conversion of G3P to RuBP energy and it is coupled to O requires; conversion of ATP to ADP + Pi releases; conversion of NADPH to NADP+ releases; conversion of ADP + Pi to ATP , requires; conversion of NADP+ to NADPH Question 3 (1 point) Which feature is shared by both chloroplasts and mitochondria? Electrons flow from NAD(P)H to O2. They both have an outer membrane, and inner membrane, and a matrix. They both have proton gradient across their inner membrane. Anrotan gradient is.coupled to ATP synthesis What would happen to the light reactions if the Calvin cycle stopped conven NADPH to NADP+? The light reactions would speed up because plants need the Calvin cycle t survive and increasing the light reactions increases the Calvin cycle. The light reactions would stop because NADP+ is needed to accept electron from the light reactions. The light reactions would continue because they make NADPH for the Calvin cycle but do not depend on the Calvin cycle for anything. The light reactions would continue because all they require is light and water to make O2 and ATP. Next Page Page 2 of 3 Call

Answers

1) The conversion of G3P (glyceraldehyde 3-phosphate) to RuBP (ribulose 1,5-bisphosphate) in the Calvin cycle requires energy and is coupled to the conversion of ATP to ADP + Pi. (Option a)

2) The feature shared by both chloroplasts and mitochondria is that they both have a proton gradient across their inner membrane, which is coupled to ATP synthesis. (Option D)

3) The light reactions would stop because NADP+ is needed to accept electrons from the light reactions. (Option B)

What is G3P?

G3P (glyceraldehyde-3-phosphate) is a three-carbon sugar molecule produced during the Calvin cycle of photosynthesis. It is used to synthesize glucose and other organic compounds


1) The conversion of G3P (glyceraldehyde 3-phosphate) to RuBP (ribulose 1,5-bisphosphate) during the regeneration phase of the Calvin cycle requires energy input in the form of ATP (adenosine triphosphate).

2) Both chloroplasts and mitochondria generate ATP through the process of chemiosmosis, which involves the movement of protons (H+) across a membrane from an area of high concentration to an area of low concentration. The energy from this movement is used to drive the production of ATP.


3) The light reactions generate ATP and NADPH, which are used in the Calvin cycle to fix CO2 into organic molecules. NADP+ is required to accept the electrons from NADPH produced in the light reactions, and without NADP+, the NADPH cannot be oxidized and used to power the Calvin cycle. As a result, the buildup of NADPH would cause a feedback inhibition of the light reactions, and they would eventually stop.

Learn more about G3P on:

https://brainly.com/question/29886968

#SPJ1

Full Question:

Although part of your question is missing, you might be referring to this full question:

Conversion of G3P to RuBP _ energy and it is coupled to

A) requires; conversion of ATP to ADP + Pi

B) releases; conversion of NADPH to NADP+

C releases; conversion of ADP + Pi t(bATP

D) requires; conversion of NADP+ to NADPH

Which feature is shared by both chloroplasts and mitochondria?

A) Electrons flow from NAD(P)H to 02.

(B)They both have an outer membrane, and inner membrane, and a matrix.

C) They both have proton gradient across their inner membrane.

D) A proton gradient is coupled  to ATP synthesis


What would happen to the light reactions if the Calvin cycle stopped converting NADPH to NADP+?

A) The light reactions would speed up because plants need the Calvin cycle

survive and increasing the light reactions increases the Calvin cycle.

B) The light reactions would stop because NADP+ is needed to accept electro from the light reactions.

C) The light reactions would continue because they make NADPH for the Calvin cycle but do not depend on the Calvin cycle for anything.

D) The light reactions would continue because all they require is light and water to make 02 and ATP.

The _____ lobes are involved with hearing, language comprehension, memory and some emotional control. A. frontal. B. occipital. C. posterior. D. temporal.

Answers

The temporal lobes are involved with hearing, language comprehension, memory and some emotional control. So, option D is correct.

The brain's temporal lobes are parts that are situated above and behind the ears on the sides of the head. Several crucial processes are carried out by the temporal lobes, including:

Auditory processing: Processing of auditory information is done by the primary auditory cortex, which is a part of the temporal lobes.

Language comprehension: The left temporal lobe, in particular, is essential for interpreting both spoken and written language.

Memory: Both short-term and long-term memory are stored in and retrieved by the temporal lobes.

Emotional processing: The recognition of facial expressions and the interpretation of emotional tone of voice are two examples of how the temporal lobes are engaged in the processing of emotions.

A variety of neurological problems, including hearing loss, language disorders, memory loss, and adjustments in emotional control, can be brought on by damage to the temporal lobes.

To know more about temporal lobes

brainly.com/question/29459826

#SPJ4

Which type of consumer is missing from this food chain?Food chain connected by right arrows from Raspberry bush to Rabbit to Owl

Question 4 options:

decomposer


herbivore


consumer


producer

Answers

Answer:

Decomposer

Explanation:

Food chain is mostly in the following order

Producer → Herbivore → Carnivore/Omnivore → Predators (owl)→ Decomposer

In the given food chain,

Raspberry bush is producer

Rabbit is herbivore

Owl can be considered as carnivore/omnivore/predator.

so, here decomposer is the missing level in the food chain.

1. Discuss Dr. Lustig’s response when asked if sugar is toxic.2. Summarize the subsidy and insurance models described by Dr. Lustig, why they are at odds with each other, and what he suggests is the solution to changing the food supply in the United States.3.Explain what differential subsidization is and summarize the example Dr. Lustig provides, as well as how it can be put into action in the United States.

Answers

Dr. Lustig believes that sugar is a toxic substance. He believes that sugar is the cause of many chronic diseases that are rampant in the United States.

He also believes that sugar is a drug that is as addictive as cocaine. He suggests that sugar be regulated like alcohol and tobacco to control its usage. Dr. Lustig described the subsidy and insurance models that are at odds with each other. The subsidy model supports the production of crops such as corn and soybeans, which are used to produce junk food. The insurance model supports the treatment of chronic diseases that result from the consumption of junk food.

Dr. Lustig suggests that the solution to changing the food supply in the United States is to subsidize the production of healthy foods and to tax junk food. Differential subsidization is the practice of providing subsidies to specific crops that are healthier than others. Dr. Lustig provides the example of a subsidy for broccoli. Broccoli is a healthy vegetable that is rich in nutrients and has a low glycemic index. A differential subsidy for broccoli would encourage farmers to grow it and would make it more affordable for consumers.

Dr. Lustig believes that sugar is a toxic substance. He believes that sugar is the cause of many chronic diseases that are rampant in the United States. Differential subsidization can be put into action in the United States by providing subsidies to farmers who grow healthy crops and by increasing the price of junk food through taxes.

To know more about Chronic disease please visit :

https://brainly.com/question/26032685

#SPJ11

At which stage is meiosis 1 do the pairs of homologous chromosomes come together?

Answers

Answer:

The pairing of homologous chromosomes occurs during the first stage of meiosis, known as prophase I. Specifically, during the early stages of prophase I, the homologous chromosomes find each other and come together to form a tetrad, which consists of two pairs of sister chromatids (four chromatids in total). This pairing is also known as synapsis and it allows for the exchange of genetic material between the homologous chromosomes through a process called crossing over.

true or false natural selection can cause changes within species, but it cannot explain modifications that lead to new species.

Answers

Natural selection can cause changes within species, but it cannot explain modifications that lead to new species. So the statement is true.

Natural selection is the biological process that enables living beings to adapt to their surroundings over time. It is responsible for determining which characteristics are passed down from one generation to the next, making offspring more likely to survive and reproduce in the current environment. There are four basic steps to the process of natural selection:

Variation: Some of these characteristics are inherited from parents, while others are acquired through life, such as scars or tattoos.Inheritance: The offspring inherit a mixture of traits from their parents, which can result in new variations over time.The struggle for survival: In nature, there is more competition for resources than there are resources. Selection: When only the strongest and most adaptable offspring survive, the best traits are passed down from one generation to the next.

Learn more about natural selection: https://brainly.com/question/23929271

#SPJ11

where is the blastocyst located in the woman’s body?

Answers

The blastocyst is located in a woman's uterus.

The blastocyst is a stage of the  human embryo which  generally develops four to five days after fertilization. After the egg is fertilized, it travels through the fallopian tube and attaches itself to the uterine wall, where it begins to develop. The blastocyst consists of an  external layer of cells called the trophectoderm,

and an inner group of cells called the inner cell mass. The trophectoderm is the layer that will come the placenta, and the inner cell mass will  ultimately come the embryo. The blastocyst is a  veritably important stage in the development of the embryo, as it's the point at which the embryo begins to form the organs and tissue that will  ultimately form the baby.

To know more about blastocyst visit:

https://brainly.com/question/30512924

#SPJ4

which enzyme seals okazaki fragments together during dna replication?

Answers

Nevertheless, DNA ligases are involved mainly in any step that calls for sealing the phosphodiester bonds from of the DNA backbone. They are well recognised for their function in uniting adjacent Okazaki fragments just at lagging strand of a replication fork.

Okazaki fragments are produced on the lagging strand as a result of this discontinuous synthesis. When DNA polymerase I detects a "nick" or break inside the phosphate backbone, it takes out each RNA primer and inserts DNA into the empty spaces. The phosphate backbone is subsequently covalently joined by DNA ligase. Even as helix unwinds, DNA synthesis just on lagging strand restarts numerous times, resulting in numerous brief pieces known as "Okazaki fragments." The Okazaki pieces are joined into the a single DNA molecule by the enzyme DNA ligase.

Learn more about DNA

https://brainly.com/question/264225

#SPJ4

This superficial muscle covers a large part of the posterior thorax. A. Rhomboids B. Pectoralis major. C. Trapezius D. Rectus abdominis.

Answers

The superficial muscle that covers a large part of the posterior thorax is the Trapezius muscle (Option C). The Trapezius muscle is a large, triangular-shaped muscle that extends over the upper back and posterior neck.

It is responsible for movement and stabilization of the shoulder blade and neck, and it is commonly involved in neck and shoulder pain. The Rhomboids (Option A) are deep muscles located between the shoulder blades and are responsible for retracting or squeezing the shoulder blades together.

The Pectoralis major (Option B) is a large muscle located in the chest that is responsible for movement of the arm and shoulder joint.

The Rectus abdominis (Option D) is a paired muscle located in the abdomen that is responsible for flexing the trunk and compressing the abdominal contents.

Learn more about  superficial muscle

https://brainly.com/question/30704848

#SPJ4

cell body with a single process that divides into two branches and functions as an axon ; only the receptor ends of the peripheral (distal) process function as dendrites is called?

Answers

Cell body with a single process that divides into two branches and functions as an axon only the receptor ends of the peripheral process function as dendrites is called as biphasic neuron.

The receptor ends of the  supplemental( distal) process function as dendrites, while the proximal process functions as an axon. Biphasic neurons are  set up in the  supplemental nervous system and are involved in the transmission of impulses from the  sensitive receptors to the central nervous system.

The main function of biphasic neurons is to bear electrical signals from one neuron to another. Biphasic neurons have an important  part in controlling muscle movement, regulating hormonal  concealment, and transmitting  sensitive information from the body to the brain.

To know more about axon visit:

https://brainly.com/question/29790232

#SPJ4

Match the following statements with either Adrenal Medulla (Nervous System), Adrenal Cortex (Endocrine System) or Both.

Please help answer all of them if possible!!

Answers

Adrenal cortex - hormones secreted are cortisol and aldosterone,  stimulated by ACTH from anterior pituitary to release hormones.

What are the functions of cortisol?

Your adrenal glands create the glucocorticoid hormone cortisol, which is then released into the body.

Hormones are substances that communicate with your organs, skin, muscles, and other tissues through your blood to coordinate various bodily functions. These messages instruct your body on what to do when.

A particular class of steroid hormone is glucocorticoids. They regulate the metabolism of your muscles, fat, liver, and bones while reducing inflammation in all of your bodily tissues. The sleep-wake cycle is also impacted by glucocorticoids.

Explanation.

Adrenal medulla- hormones stimulate fight or flight responses, tissue in  middle of adrenal gland, hormones are epinephrine and norepinephrine, hormones respond to stress.

To know more about Adrenal Gland, visit:

https://brainly.com/question/12499901

#SPJ1

maintenance of posture and production of heat are functions of ______ muscle.a) Skeletal muscle b) Smooth muscle c) Cardiac muscle d) Adipose tissu

Answers

Skeletal muscle is responsible for the production of heat and the maintenance of posture.

Is it the muscles that control posture?

Muscle contraction helps maintain posture, such as sitting and standing. The skeletal muscles are constantly fine-tuning their positions to keep the body still. Numerous muscles' tendons extend over joints, assisting in joint stability.

What roles do they play in body posture and heat production?

Movement, posture, joint stability, and heat production are the four functions that are performed by muscle contraction. Skeletal, smooth, and cardiac muscle are the three types of muscle. Endomysium surrounds each muscle fiber. Perimysium covers the bundles of fibers as they are collected.

To know more about Skeletal muscle visit :-

https://brainly.com/question/1560716

#SPJ1

i can only breathe out of one nostril and it switches is called

Answers

The condition in which a person can only breathe out of one nostril at a time and the airflow switches between nostrils periodically is known as nasal cycle.

The Nasal Cycle is the process of alternating airflow between the nostrils. This cycle of nasal airflow results from the nasal tissues' rhythmic expansion and contraction. During this cycle, one nostril is dominant, while the other is passive, and it occurs roughly every two and a half hours. The nostril that is dominant alternates every few hours, resulting in both nostrils receiving air that is equally distributed.

The process of breathing through one nostril and then switching to the other is known as the nasal cycle.

The nasal cycle is normal and natural, and it serves a variety of functions, including:- Warm and moisten the air- Prevent drying of the nasal membranes- Provide regular cleaning of the nasal passages- Enhance the sense of smell by alternating the exposure of each nostril to odors- Regulate the airflow and prevent overstimulation of the olfactory receptors.

The nasal cycle is a healthy and necessary process, and it usually goes unnoticed. However, if a person has a condition that affects their nasal cycle, such as nasal polyps or a deviated septum, they may have difficulty breathing.

For more question on nasal cycle click on

https://brainly.com/question/10215614

#SPJ11

Fill in the blanks blank a. _______secrete hormones into the bloodstream, whereas_________ secrete substances into ducts and onto the skin or the lumen of a hollow organ. b. ________Goblet cells and mammary glands are both exocrine glands--how are they similar and how are they different?

Answers

(a) Endocrine glands secrete hormones into the bloodstream, whereas exocrine glands secrete substances into ducts and onto the skin or the lumen of a hollow organ.

(b). Goblet cells and mammary glands differ in the type of substance they secrete and the location where they secrete it.

What is endocrine gland?

An endocrine gland is a type of gland that secretes hormones directly into the bloodstream. Hormones are chemical messengers that travel through the bloodstream to target cells or organs and have a variety of functions in the body, including regulating growth and development, metabolism, and reproduction.

Examples of endocrine glands in the human body include;

the pituitary gland, thyroid gland, adrenal gland, and pancreas.

Goblet cells secrete mucus onto the surface of epithelial tissues, while mammary glands secrete milk into ducts that lead to the nipples.

Learn more about endocrine glands here: https://brainly.com/question/29213361

#SPJ1

Identify the incorrect statement regarding the vitreous body. View Available Hint(s) Hint 1. The vitreous body fills the posterior segment. O Supports the posterior surface of the lens O Holds the retina against the choroid O Consists of a thin, watery fluid O Transmits light Submit Previous Answers Request Answer X Incorrect; Try Again; 5 attempts remaining

Answers

The incorrect statement regarding the vitreous body is that it consists of a thin, watery fluid. In fact, the vitreous body is a clear, gelatinous substance that fills the posterior segment of the eye.

It supports the posterior surface of the lens and holds the retina against the choroid, providing the eye with its shape and helping to maintain its structural integrity. It is not a thin, watery fluid and instead has a gel-like consistency due to the presence of collagen fibers and hyaluronic acid. While the vitreous body is not involved in transmitting light, it does play an important role in the optical properties of the eye.

To know more about vitreous click here:

brainly.com/question/30158908

#SPJ4

Arrange the following in order from smallest to largest: fascicle, myofilament, muscle cell, myofibril, sarcomere
Myofilament, myofibril, muscle fiber, fascicle, muscle

Answers

The order from smallest to largest is myofilament, myofibril, sarcomere, fascicle, and muscle cell.

Myofilaments are made up of the proteins actin and myosin, which are the smallest components of the muscle.

Myofibrils are made up of a bundle of myofilaments and are the next smallest.

Sarcomeres are the next smallest and are made up of alternating thick and thin filaments that overlap to create a repeating pattern.

Fascicles are the next smallest and are a bundle of muscle fibers.

Lastly, muscle cells are the largest and contain multiple fascicles.

Thus, the order, from smallest to largest is Myofilament, myofibril, sarcomere, fascicle, and muscle cell.

Learn more about myofilament here:

https://brainly.com/question/10671711

#SPJ11

explain how you can avoid injury to bones and joints.

Answers

To avoid injury to bones and joints, it is important to practice good posture, maintain a healthy weight, and engage in regular physical activity to strengthen muscles and bones.

Warming up before exercise, using proper form and technique, and gradually increasing the intensity of physical activity can also help prevent injury. Wearing appropriate protective gear, such as helmets and pads, can be important for high-risk activities such as contact sports.

Additionally, avoiding repetitive movements and taking breaks during prolonged periods of physical activity can help reduce the risk of injury. Finally, it is important to listen to your body and seek medical attention if you experience pain, swelling, or other signs of injury.

To learn more about bones refer to

brainly.com/question/5482443

#SPJ4

what part of the eye protects the pupil and redirects light?

Answers

The iris is the part of the eye that protects the pupil and redirects light. The

iris is a thin, circular structure located between the cornea and the lens, and it gives the eye its characteristic color. The opening in the center of the iris is the pupil, which regulates the amount of light entering the eye.

The iris contains smooth muscle fibers that contract or relax to adjust the size of the pupil in response to changes in light levels. The iris also helps to redirect light by changing the angle at which it enters the eye, ensuring that it falls on the retina in a way that allows for clear vision.

To learn more about eye refer to

brainly.com/question/15686038

#SPJ4

What body type is characterized by a solid, muscular, and large-boned physique?

Answers

The body type that is characterized by a solid, muscular, and large-boned physique is the mesomorph body type.

A mesomorph is a body type classification used to describe people with a medium to large bone structure and an athletic build. Mesomorphs have a naturally lean, muscular, and athletic body type. They have broad shoulders, a small waist, and a large chest and legs.

Mesomorphs are gifted athletes who can quickly build muscle mass and are excellent at sports that require strength and power, such as weightlifting, football, and wrestling. The mesomorphic body type is characterized by a solid, muscular, and large-boned physique.

Mesomorphs are naturally athletic, and their bodies are built for strength and power. They have broad shoulders, a small waist, and a large chest and legs, giving them an overall muscular appearance.

For such more question on mesomorph:

https://brainly.com/question/27967905

#SPJ11

arrange the steps that would be used in a laboratory to engineer a bacterium that could express the human gene coding for insulin1.Transform the vector into an E. coli bacterium.2.Generate cDNA of the insulin gene using reverse transcriptase.3. Insert the insulin cDNA into a bacterial vector near a promoter site.4. Isolate the mRNA of the insulin gene.

Answers

The steps that would be used in a laboratory to engineer a bacterium that could express the human gene coding for insulin are:

1. Generate cDNA of the insulin gene using reverse transcriptase.

2. Insert the insulin cDNA into a bacterial vector near a promoter site.

3. Transform the vector into an E. coli bacterium.

4. Isolate the mRNA of the insulin gene.

The method for genetically engineering a bacterium to express the human gene coding for insulin

 Generation of insulin gene CDNA.

The first step in genetically engineering a bacterium to express the human gene coding for insulin is to generate a cDNA of the insulin gene using reverse transcriptase.

Insulin cDNA InsertionThe next step involves inserting the insulin cDNA into a bacterial vector near a promoter site. This is necessary to ensure that the bacterium can produce the insulin gene.

Transformation of Bacterial VectorThe third step involves transforming the vector into an E. coli bacterium. This process involves the use of special enzymes to insert the DNA into the bacterial cell.

Isolation of mRNAFinally, the last step involves isolating the mRNA of the insulin gene. This process is necessary to ensure that the gene is properly expressed and that the bacterium can produce insulin in significant amounts.

To learn more about human gene coding: https://brainly.com/question/13845958

#SPJ11

the open area or central space in the gi tract is called the

Answers

Answer:

The Lumen

Explanation:

hope this helps

Summarize how the fossil cetacean ancestors changed over time. Give at least one example of a specific trait and how it changed

Answers

The cetacean ancestors, which were land-dwelling mammals, changed over time through a series of evolutionary adaptations that eventually led to their transformation into aquatic animals such as whales, dolphins, and porpoises.

One of the key changes involved the evolution of their limbs, which gradually transformed into flippers for efficient swimming. Over time, their nostrils moved from the front of their snouts to the top of their heads, forming blowholes, allowing them to breathe while swimming. Another change was the development of a streamlined body shape, reducing drag and making swimming more efficient. One specific trait that changed was their teeth. The earliest cetacean ancestors had teeth similar to their land mammal ancestors, but over time, their teeth became more specialized for hunting and capturing prey underwater, with some species losing teeth entirely and developing baleen instead.

To know more about mammals click here:

brainly.com/question/23090690

#SPJ4

Think of a scenario where wolves are introduced to an island where elk live. This elk population has not been in contact with wolves for thousands of years. Which of the following is most plausible. a. The carrying capacity and "r" of the elk population will increase. b. There is an evolutionary arms race, where elk evolve defenses as wolves continue to evolve to overcome those defenses. c. The wolf population will not persist more than a year because the elks are not accustomed to reacting to wolf predators. d. Elk behavior will not change in any way. e. The survivorship of elk increases.

Answers

When wolves are introduced to an island where elk live, then "an evolutionary arms race will occur, where elk evolve defenses as wolves continue to evolve to overcome those defenses" because, wolves are natural predators. Thus, the correct option is B.

What is the plausible effect?

Wolves are a natural predator of elk. The introduction of wolves to an island where elk have lived for thousands of years will result in an evolutionary arms race, in which elk evolve defenses to protect themselves from the new predators.

The carrying capacity and "r" of the elk population will not increase, and the wolf population will persist for more than a year because elks will adapt to the new threat, or the less fit elk individuals will be removed from the population, resulting in changes in the population structure. Elk behavior will also change in response to the new threat, and survivorship may increase for individuals that develop stronger defenses.

Therefore, the correct option is B.

Learn more about Evolutionary arms race here:

https://brainly.com/question/17831371

#SPJ11

based on the data provided, explain how cellular processes must be altered in stomach cancer cells compared with normal stomach cells to result in the different levels of sirt3 expression observed. a mutation to the gene encoding a cyclin-dependent kinase (cdk ) in human stomach cells results in a cdk that is continually active in the cells. explain why the continually active cdk will most likely change the normal cells into cancer cells.

Answers

One way in which this alteration can occur is through a mutation in the gene encoding a cyclin-dependent kinase (CDK) in human stomach cells.

Mutation of the gene encoding a cyclin-dependent kinase (CDK) results in a CDK that is continuously active. This means that the cell cycle will no longer be able to stop at certain checkpoints, allowing cancer cells to divide without the usual growth control and differentiation, leading to increased expression of sirt3.

Continued activation of CDK in cells can also lead to the accumulation of DNA damage. This accumulation of damaged DNA can cause mutations in genes, which can ultimately lead to the development of cancer.

Cyclin-dependent kinases are enzymes that regulate the cell cycle and control its proper development.

More about CDK at https://brainly.com/question/13050465

#SPJ11

which of the following statements accurately compares the atp synthase enzymes of chloroplasts and mitochondria?

Answers

ATP synthase enzymes are found in both mitochondria and chloroplasts, and they both produce ATP by chemiosmosis.

What features of mitochondria and chloroplast are similar and different?

The mitochondria, or "powerhouses," of the cell, consume fuel molecules and produce energy during cellular respiration. Chloroplasts are found in both plants and algae. They are in responsible of gathering light energy, which is used to make carbohydrates during photosynthesis.

Which of the following statements concerning chloroplasts and mitochondria supports the endosymbiotic theory?

Prokaryotes including bacteria, mitochondria, and chloroplasts all have circular DNA. This supports the Endosymbiotic Hypothesis, which postulates that the mitochondria and chloroplast in eukaryotic cells were formed by a significant amount of anaerobic bacteria consuming aerobic bacteria (prokaryotes) (prokaryote).

To know more about mitochondria visit:-

https://brainly.com/question/10688306

#SPJ1

let's say the 6th nucleotide in the original dna sequence changes from an a to a c. do you think that would effect the activity of the protein? why or why not?

Answers

Yes, changing the 6th nucleotide in the original DNA sequence from an A to a C would affect the activity of the protein. This is because the sequence of nucleotides in DNA determines the sequence of amino acids in proteins, and changing even a single nucleotide can cause a change in the amino acid sequence which can, in turn, affect the structure and function of the protein.

The genetic code is made up of codons, which consist of three nucleotides that correspond to a specific amino acid. Changing one nucleotide can alter the codon, which can then lead to a different amino acid being incorporated into the protein. Depending on the location of the amino acid change, it can affect the activity of the protein in various ways. For example, if the changed nucleotide leads to a different amino acid being incorporated into the protein, the protein may not fold correctly, which can affect its function.

Learn more about genetic code: https://brainly.com/question/22632342

#SPJ11

when a stimulus is applied to a receptor in the skin, an action potential is propagated along a neuron to the brain, where another signal is sent back to the muscle for a response. which of the following best describes what occurs when the action potential reaches a chemical synapse at the end of an axon

Answers

When a stimulus is applied to a receptor in the skin, an action potential is propagated along a neuron to the brain, where another signal is sent back to the muscle for a response. When the action potential reaches a chemical synapse at the end of an axon, neurotransmitters are released into the synaptic cleft, which then binds to receptor proteins on the postsynaptic membrane.

When the action potential arrives at the end of the presynaptic neuron, it induces the opening of voltage-gated calcium ion channels. This allows calcium ions to enter the presynaptic neuron, causing synaptic vesicles containing neurotransmitters to fuse with the presynaptic membrane.

The neurotransmitters are then released into the synaptic cleft, where they bind to specific receptor proteins on the postsynaptic membrane. This leads to the opening of ion channels on the postsynaptic membrane, causing depolarization and the generation of a new action potential in the postsynaptic neuron. This action potential is then propagated along the postsynaptic neuron, leading to the transmission of the nerve impulse through the nervous system. Therefore, neurotransmitters play an important role in the transfer of information between neurons at chemical synapses.

Learn more about neurotransmitters at:

https://brainly.com/question/14783379

#SPJ11

what is produced in plant cells if the cell has run out of oxygen reserves

Answers

It  reserves alcohol + co2. If a plant cell has run out of oxygen reserves, it will undergo anaerobic respiration, also known as fermentation.

During anaerobic respiration, the cell will produce energy in the absence of oxygen by breaking down glucose through a series of chemical reactions. The end products of anaerobic respiration in plant cells are usually different from those in animal cells.

In plant cells, the most common end products of anaerobic respiration are ethanol (alcohol) and carbon dioxide. This process is known as alcoholic fermentation. Some plant cells, such as those in the roots of some plants, can also produce other organic acids such as lactic acid or acetic acid during anaerobic respiration.

Anaerobic respiration is less efficient than aerobic respiration, which requires oxygen, so it produces less energy per molecule of glucose. However, it allows the cell to continue producing some energy even in the absence of oxygen, which can be important in certain conditions such as flooding or low-oxygen environments.

Learn more about “  anaerobic respiration “ visit here;

https://brainly.com/question/12605249

#SPJ4

Other Questions
when an ecosystem is disturbed by fire or toxic chemicals, what affects it will be? Why Pluto left the solar system? What is the mass of Pluto? If I heated up a glass of 100 grams of water, and the temperature changed from 25 to 31, how much heat was needed to do that (in calories)? Compare and contras:what were Hamiltons and Jeffersons veiw on the power of federal government?(compare and contrast at least 2 veiws each had.)(5-7 sentences) T/F. Endocrine disease results in either an abnormal increase in hormone production, or hypersecretion, or an abnormal decrease, or hyposecretion. Find the derivative of the function f(x), below. It may be to your advantage to simplify first. f(x)=x5xf(x)= If you run towards a faraway friend at 5 miles per hour and she bikes towards you at 15 miles per hour, how many miles closer are you to each other after 1 hour? Melissa is an engineer at Acme Consulting. She used to work from 8:30am to 5:30pm, but her boss told her she could come in at 9am because of her great performance last year. However, this year Melissa is constantly arriving late to work. Her supervisor is looking to utilize extinction to remedy this behavior. Which of the following would be an example of extinction in this situation?Multiple ChoiceHaving Melissa go back to working from 8:30am to 5:30pmFiring MelissaReducing Melissas compensationProviding Melissa with additional compensation if she arrives to work by 9amHaving Melissa attend leadership training Two teams, A and B, play in a series. Team A has a 60% chance of winning each game, independent of other games. The series ends and a winner is declared when one of the teams has won two more games than the other team. (a) What is the expected number of games played? (b) Given that Team B wins the first game, what is the probability that the series will last at least 8 games? the mass of a particular bar of gold-pressed latinum (from star trek) has a mass of 100 grams. what is the mass of this bar when it is brought to the moon? true or false for which of the following could you volunteer so that you could gain experience for a career in a related field? which of the following statements regarding political and economic cooperation of the european union (eu) is correct? En Espaa hay muchos 1 of 1. Question 2 with 1 blankRonaldinho y Ronaldo son dos futbolistas (soccer players) 1 of 1 famosos. Question 3 with 1 blankLa rivalidad entre el Bara y el Real Madrid es comparable con la rivalidad entre los Yankees y los 1 of 1 en bisbol. Question 4 with 1 blankMari Carmen piensa que David Beckham es 1 of 1 Add some source code files to compile. Output a half pyramid of stars with a height determined by the user. If the user enters a number less than one, exit. Hint: See chapter 4's discussion of this type of problem. Test Case 1 Standard Input 5 Required Output Enter a height in * in in In *** n ***** in Standard Input 10 Required Output Enter a height\n in In ** ***** I\n ***** in ***** in \n n in who helped liberate venezuela, colombia, panama, bolivia, ecuador and peru from spain? What is the answer to this question? the sides of a triangle have lengths 15, 20, 25. find the length of the shortest altitude of the triangles. fill in the blank. Zipster is engaging in ______. diversification Corporate strategy needs to be dynamic over time in order to allow firms to do which of the following? which intermolecular force is due to the formation of an instantaneous dipole? 38. Which of the following procedures most likely would give the greatest assurance that securities held as investments are safeguarded?A. There is no access to securities between the year-end and the date of the auditor's security count.B. Proceeds from the sale of investments are received by an employee who does not have access tosecurities.C. Investment acquisitions are authorized by a member of the Board of Directors before execution.D. Access to securities requires the presence of two designated officials.