Answer:
Tt and tt
Explanation:
Dominant alleles are written with capital letters.
Recessive alleles are written with lowercase letters.
When an allele is dominant, the individual only needs one copy of it in order for the trait it codes to be expressed.
When an allele is recessive, the individual needs to have two copies of it in order for the trait it codes to be expressed.
Given the gene T/t, which determines the ability to taste PTC, there are 3 possible genotypes for a person:
TT, homozygous taster.Tt, heterozygous tastertt, homozygous non-tasterThe cross between a heterozygous taster with a non-taster would be:
Tt x ttThe fauces, one of the seven openings found in the pharynx, opens into the:
a. oropharynx.
b. nasopharynx.
c. esophagus.
d. Both A and B are correct
Answer:
a. oropharynx.
Explanation:
oropharynx -
It is basically the mouth area of the body , and one of the seven openings that is found in the pharynx .
It is one of the part in throat present behind the mouth and the oral cavity . The area behind the oral cavity , including soft palate , tongue , the tonsils and the back wall of the throat .
Hence , the correct answer is - oropharynx .
Action potentials pass from one myocardal cell to another through areas of low electrical resistance called
a. gap junctions
b. fibrous heart rings
c. electromagnetic discs
d. sarcolemma sclerotic plaques
e. tight junctions
Answer: a. Gap junctions
Explanation:
The electrical activation or potential initiate and transfer from one cell to another through gap junction. The gap junctions transfers proteins , ions and small molecules from cell to cell required for electrical conduction.
Funny bone is called?
Answer:
The answer is: ulna nerve
Explanation:
The ulna nerve, also known as the funny bone, is a major nerve present alongside the ulna bone. This nerve is not protected by any bone or muscle, therefore, it is the most extensive unprotected nerve in the human body.
This is because when the ulna nerve gets bumped, the individual experiences an electric shock-like sensation.
The funny bone refers to the ulnar nerve, which plays an important role in hand functionality and sensibility.
The 'funny bone' is actually not a bone at all, but rather a term commonly used to refer to the ulnar nerve, which runs along the inner side of the elbow. This nerve runs through a groove in the humerus bone, which is part of the upper arm. When you hit your funny bone, you are actually striking this nerve, and it can cause a tingling sensation or numbness in the ring and little fingers, which can feel quite odd and sometimes painful.
Location: The ulnar nerve is located on the medial aspect of the forearm, running down the inside of the arm and into the hand.
Function: The ulnar nerve is responsible for sensation in the little finger and half of the ring finger, as well as controlling some muscles in the hand that are crucial for fine movements.
When it Hurts: The sensation you feel when you bump your funny bone is due to the ulnar nerve being compressed against the hard surface of the elbow. This causes a temporary disruption in the nerve's signals, leading to tingling and discomfort.
Why it’s Funny: The term 'funny bone' may come from a play on words—'funny' refers to the odd sensation experienced, while 'bone' might mistakenly suggest it's an actual bone being hit.
Prevention: To avoid bumping your funny bone, be mindful of your movements, especially when in tight spaces or when using your arms to reach or grab.
Which enzymes break down carbs, lipids, and proteins and where they are secreted from?
Answer:
Catabolism is method by which large complex molecules like lipids, proteins and carbohydrates are broken down into the simpler smaller molecules.
Protease or peptidase are the enzymes that catalyzes the breakdown of proteins into amino acids or smaller polypeptide units. The protease enzyme pepsin is secreted in the stomach; and trypsin and chymotrypsin is secreted in the pancreas.
Amylases are the enzymes that breaks down the complex carbohydrates to simple sugars. The enzyme salivary amylase is secreted by the salivary gland in mouth and the enzyme pancreatic amylase is secreted by pancreas.
Lipases are the enzymes that catalyzes the breakdown of lipids or fats. Lipases are secreted in the mouth, stomach, and pancreas.
The structures that deflect air as it passes through the nose are called
a. choanac.
b. paranasal sinuses.
c. conchae.
d. vibrissae.
Answer: Conchae
Explanation:
The respiration is a process that can be defined as exchange of gases in between lungs and outer environment.
The enter the body through nose an then passes through nasal passage. The structure that helps in the deflection of air is known as conchae.
The vibrissae in the vestibule provides filter as it screens the particulate matter present in inhaled hair.
Hence, the correct answer is option A
The important feature of the target cells that allows them to respond to hormones is the
A. Proximity to the source of the hormone
B. Type of nerve supply of the target cell.
C. Type of nerve supply to the target cell.
D. Presence of appropriate receptor molecules.
E. Surface area of the target cell membrane.
Answer: D. Presence of appropriate receptor molecules.
Explanation:
Various hormones circulates over the entire body, they come in contact with almost every cell of the body but it usually affects the limited number of cells which are called as target cells. The target cell will respond to the hormone because it posses the receptor molecules for providing the desired action for the hormonal cell interaction.
The leading cause of kidney failure in the United States is ________.
Answer:
The answer is: Diabetes
Explanation:
In the United States of America, diabetes is the leading cause of kidney failure.
Diabetes is a serious medical condition, characterized by prolonged high blood sugar levels in the human body. It is caused due to the insufficient production of insulin or cells of the body being unresponsive towards the produced insulin.
Complications of this disease include kidney failure, cardiovascular disease, stroke, eye damage and foot ulcers.
Final answer:
The leading cause of kidney failure in the United States is diabetic nephropathy, a progressive kidney disease caused by poor blood sugar control in people with diabetes.
Explanation:
The leading cause of kidney failure in the United States is diabetic nephropathy. Diabetic nephropathy is a progressive kidney disease caused by damage to the capillaries in the glomeruli of the kidneys due to poor blood sugar control in people with diabetes. It is not fully understood how diabetes leads to this damage, but high levels of glucose in the blood are thought to be involved. Other risk factors for diabetic nephropathy include high blood pressure, a history of cigarette smoking, and a family history of kidney problems.
Lymph capillaries are found in the
a. epidermis
b. muscles
c. bone marrow
d. central nervous system
e. dermis
Answer:
The correct answer is e. dermis
Explanation:
Lymph capillaries are thin walled capillaries interwoven with blood capillaries and found throughout the body except nervous system, bone marrow, and tissues that do not contain vascular tissue like epidermis.
The role of lymphatic capillaries is to collect the extra fluid which is secreted by the tissues in the intercellular spaces. This fluid is called lymph and is clear and transparent and contains WBCs and plasma.
Lymph is different from blood because it do not contain RBCs and platelets. Lymphatic vessels are important part of body immunity because it contains many WBCs in their lymph helpful in fighting diseases.
At rest, most of the body's blood supply resides in the pulmonary loop.
a. True
b. False
Answer:
The answer to the statement: At rest, most of the body´s blood supply resides in the pulmonary loop, would be, B: False.
Explanation:
The circulatory system never stops working. Pumping of blood, transportation of oxygen, nutrients and water to and from tissues is a process that does not end, even during sleep. The only moment when this process does not happen, is in death. However, a good question is, where does the blood go, or stay, when the body is not active, like for example, during sleep. And the answer is that most of it will rest on the systemic veins and venules and will slowly circulate back to the heart, but at a much lower rate than when the body activates itself. However, what is not true is that blood will reside mostly in the pulmonary loop, because this loop does not have the capacity to store that much blood.
Exercise has little effect on cardiac output.
a. True
b. False
Final answer:
The statement about exercise having little effect on cardiac output is false. Cardiac output increases significantly during physical activity in order to meet the body's increased demand for oxygen and nutrients.
Explanation:
The statement "Exercise has little effect on cardiac output" is false. Cardiac output, which is the volume of blood the heart pumps per minute, increases significantly during exercise. This increase is necessary to meet the heightened demand for oxygen and nutrients by the body's tissues. In a healthy young adult, for example, cardiac output increases from about 5 liters per minute at rest to up to 20-30 liters per minute during maximal exercise.
Regular physical exercise has numerous benefits on the cardiovascular system, including improvements in mechanical efficiency of the heart and exercise tolerance. This can lead to enhanced performance in physical activities without excessive stress or fatigue. Also, exercise can lead to improvements in blood pressure, cholesterol levels, and body weight, which are all risk factors for cardiovascular disease. During exercise, the increased heart rate and stroke volume work together to boost cardiac output, which helps to circulate blood and oxygen more effectively around the body.
All steroid hormones are synthesized from ____________.
Steroid hormones are synthesized from cholesterol. This synthesis occurs in the smooth endoplasmic reticulum of cells and plays a vital role in various physiological processes.
Explanation:All steroid hormones are synthesized from cholesterol. This substance is a type of lipid that provides the basic structure for the formation of steroids in our bodies. The process of synthesis occurs within the cells, particularly in the smooth endoplasmic reticulum. This is an important process in the body because steroid hormones play vital roles in various physiological processes such as immune response, regulation of inflammation, regulation of metabolism, and much more.
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All steroid hormones are synthesized from cholesterol.
Cholesterol serves as the precursor molecule for the biosynthesis of various steroid hormones, including glucocorticoids, mineralocorticoids, and sex hormones. These hormones are crucial for regulating a wide range of physiological processes in the body. The synthesis of steroid hormones typically begins with cholesterol, which undergoes a series of enzymatic reactions in specific tissues and organs.
For example, in the adrenal glands, cholesterol is converted into glucocorticoids (such as cortisol) and mineralocorticoids (such as aldosterone). In the gonads (testes and ovaries), cholesterol is transformed into sex hormones like testosterone and estradiol. Each type of steroid hormone has its own distinct biosynthetic pathway, with various enzymes and intermediates involved.
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A hormone carries out a single a single specific function.
a. True
b. False
Answer: False
Explanation:
A hormone can have multiple function based on the cell on which it is received which means that it depends on the receptor on which the hormone is received.
A single hormone has more than one specific function as it depends on receptors because one hormone can have multiple receptors.
The same can be coupled to different intracellular pathway in the different cell types.
hence, the given statement is False, a single hormone carries out different function.
The diastolic blood pressure is the product of heart rate and stroke volume.
a. True
b. False
Answer:
b. False
Explanation:
Cardiac Output is the product of heart rate and stroke volume. It measures the amount of blood pumped by heart, specifically left ventricle in one minute. Left ventricle is chosen to calculate it because it is the one which pumps blood to the entire body.
While calculating cardiac output two components are taken. Heart rate is the measure of number of times heart beats per minute. It increases with increase in activity intensity as muscles require more energy. Normal resting heart rate range for an adult is 60-100 bpm. Stroke volume is the amount of blood pumped by left ventricle during each heart beat. It is estimated by other factors like blood pressure. If either heart rate or stroke volume or both increase, cardiac output will also increase.
State and describe the function of the three main types of lymphocytes in our body.
Explanation:
Lymphocytes are the type of the white blood cell which function as a part of immune system.
Types of Lymphocytes:
T cells
T cells are developed in thymus gland. The specialized molecule of T-cell receptor is located on surface of cell. The molecule is important in the immunity as it recognizes the antigens and thus it to bind to them.
B cells
B cells are important part of immune system. They mature in bone marrow of the humans, and in bursa organ of the birds. The cells have a protein on the surface which is known as B-cell receptor. The protein recognizes and attaches to the specific antigens.
Natural killer cells
Natural killer cells are the lymphocytes which are known to be cytotoxic. They have ability to kill the other cells in the body. The cells are important part of immune system because these cells are able to recognize infected cells.
B lymphocytes are cells that are initially produced in the yolk sac, then in the liver (during fetal life), and later in the bone marrow. They are responsible for ensuring the so-called humoral immunity, which stands out for the immune response made by the production of antibodies. These antibodies are capable of neutralizing or even destroying antigens. In addition to antibody production, B lymphocytes act as immune memory cells. These cells are able to react quickly to a new infection with the same antigen. As such, they ensure faster and more effective protection.
T lymphocytes originate from lymphoid progenitor cells found in the bone marrow. These cells leave the marrow towards the thymus. T helper lymphocytes guarantee the differentiation of B lymphocytes into plasma cells, and are therefore important for antibody production. Suppressor T lymphocytes terminate the humoral response, that is, antibody production. T lymphocytes are estimated to represent 65% to 75% of lymphocytes present in a person's blood.
NK cells (also a lymphocyte), or natural killer cells, are part of the innate immune system. These cells are able to distinguish infected or tumor cells and attack them without stimulation. Its immune response is nonspecific, unlike T and B lymphocytes, which produce responses by antigen action.
Which of the following is an accurate statement regarding regulation of pituitary hormone secretion by the hypothalamus?
A. All pituitary hormones are regulated by tropic hormones from the hypothalamus.
B. All anterior pituitary hormones are regulated by a release ing hormone from the hypothalamus.
C. All posterior pituitary hormones are regulated by a releasing hormone from the hypothalamus.
D. All anterior pituitary hormones are tropic hormones
E. None of the above.
Answer:
The correct answer is option - A.
Explanation:
Hormones their target sites are other endocrine glands and act on these endocrine glands, known as tropic hormones. The pituitary gland is one of the gland that acts as a gland that releases tropic hormones and also regulated by the other tropic hormones released by the hypothalamus.
The hypothalamus releases several tropic hormones that inhibit and promoting hormones that regulate the pituitary glands.
Thus, the correct answer is option - A.
Final answer:
The accurate statement about the regulation of pituitary hormone secretion by the hypothalamus is that all anterior pituitary hormones are regulated by releasing hormones from the hypothalamus. (Option B)
Explanation:
The correct answer to the question regarding regulation of pituitary hormone secretion by the hypothalamus is: B. All anterior pituitary hormones are regulated by a releasing hormone from the hypothalamus.
The anterior pituitary gland produces seven hormones: growth hormone (GH), prolactin (PRL), thyroid-stimulating hormone (TSH), melanin-stimulating hormone (MSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). These hormones are referred to as tropic hormones because they control the functioning of other organs. The secretion of these hormones is regulated by releasing hormones or inhibiting hormones from the hypothalamus, which travel through the hypophyseal portal system to the anterior pituitary.
The posterior pituitary is different from the anterior pituitary; it stores and releases hormones that are synthesized in the hypothalamus, such as vasopressin and oxytocin, rather than producing hormones itself. Therefore, it is not regulated by releasing hormones as the anterior pituitary is.
Discuss oxygen and carbon dioxide transport, include hemoglobin’s role, and describe any factors that influence this process.
Answer:
Explanation:
Oxygen has low solubility in water, so very little O₂ can be delivered to tissues by simply being dissolved in blood plasma. Animals use carrier proteins to transport O₂. Red blood cells contain hemoglobin, which is the carrier protein used by vertebrates.
In contrast, most carbon dioxide produced by tissues is transported in the blood to the lungs as HCO₃⁻(bicarbonate ions).
The equilibrium equation for carbon dioxide in the blood is:
CO₂+ H₂O ↔ H₂CO₃ ↔ H⁺ + HCO₃⁻Carbonic acid
The conversion to bicarbonate ions keeps the partial pressure of CO₂ in the blood plasma low, facilitating diffusion away from the tissues.
The pH of the blood affects the process. As you can see in the equilibrium equation for CO₂, an increase of this gas results in a decrease of pH because of the formation of carbonic acid. The acidic pH decreases hemoglobin's affinity for oxygen, thus stimulating the release of O₂ to the tissues (that are producing a lot of CO₂ and need oxygen).This is known as the Bohr effect.
The human body tries its best to maintain a steady state of most of the internal conditions of the body, e.g. internal temperature, blood pressure, etc. This steady state is called:
A. Body state
B. Status quo
C. Straight and steady
D. Homeostasis
E. Bodystasis
Answer:
The correct answer is D.
Explanation:
Homeostasis is dynamic state of equilibrium kept by several physical and chemical conditions.
In this state the body functions optimal and is meant to be kept despite of external aggressions. It includes many variables, such as body temperature, blood pressure, pH, electrolyte concentrations, blood sugar level.
The normal pacemaker of the heart is in the
a. bundle of His
b. ventricle
c. AV junction
d. right atrium
Answer:
The correct answer is D.
Explanation:
The normal pacemaker of the heart is the sinoatrial node (SA). It is a small mass of specialized cells located at right atrium near the entrance of the superior vena cava.
If the SA node is fail to function, a group of cells from the atrioventricular node can take over the pacemaker function.
Also the Bundle of His and the Purkinje fibers can take over pacemaker function if none of the above function properly.
Decribe the position of the Larynx.
Answer:
Explanation:
The larynx is the organ which is situated below the tract where the pharynx splits into the trachea and the esophagus. It is present in the vocal folds of the throat. It is responsible for manipulating the volume and pitch of the sound produce by the throat for speech. It other functions such as it protects the airway from choking, and it regulates the flow of air into the lungs.
The three structures found at the renal hilum are the ___________, ___________ and ___________.
Answer:
The answer is: Renal artery, Renal vessels and Renal ureters.
Explanation:
Renal hilum refers to the depression or fissure for where the nerves, ureter and the vessels, enters or exits the kidney.
In other words, renal hilum is a deep longitudinal fissure that transmits the nerves, ureter and the vessels of the kidney.
At the renal hilum, the renal artery enters, the renal vein exits, and the renal pelvis or ureter exits the kidney.
The resting cardiac output from the left ventricle is about 5 liters.
a. True
b. False
Answer:
The correct answer is A.
Explanation:
For a young, healthy person, weighing 70kg, resting cardiac output is approximately 5 liters per minute (assuming a heart rate of 70 bpm)
70ml stroke volume x 70 beats per minute = 5 liters/min
Stroke volume is the amount of blood ejected by the left ventricle with each contraction (normal value 70ml)
Immunoglobulins that are most abundant and are responsible for resistance against many viruses, bacteria, and bacterial toxins are
A) IgG.
B) IgE.
C) IgD.
D) IgM.
E) IgA.
Answer:
The correct answer is A) IgG
Explanation:
IgG immunoglobulins are the most abundant antibodies constituting about 70-75% of total immunoglobulins present in the human serum. They have a half life of 7-21 days. These antibodies is produced and released by plasma B cells.
Function: IgG antibody is responsible for resistance against many viruses, bacteria, and bacterial toxin therefore they protect our body from these infections.
IgG antibody binds to the pathogen and carry them to phagocytic cells which eliminate them by phagocytosis. They also activate complement system which is very efficient in killing of various types of pathogens.
Thus, the correct answer is A) IgG.
The right ventricle pumps blood to the
A) left atrium.
B) right atrium.
C) aorta.
D) left ventricle.
E) right and left lungs.
Answer:
E.
Explanation:
The right ventricle pumps blood into the pulmonary arteries, which carry deoxygenated blood to the lungs to perform the gas exchange, once this occurs, the oxygenated blood returns to the heart through the pulmonary veins and enters into the left atrium, which sends the blood to the left ventricle to be pumped into the aortic artery that carries oxygenated blood to be distributed in all the body tissues, where it is exchanged again for deoxygenated blood that returns to the heart through the cava veins and enters into the right atrium to be sent to the right ventricle and start a new cycle.
What are the challenges of conducting a research project that is
CBPR?
Answer:
Explanation:
The Community-based participatory research (CBPR) is an approach which collaborate the researchers and other community members so as to facilitate their contribution and help in making decisions related to a new research. It is with the growing popularity because of the fact that it is utilizing the research strategies to engage the communities to the health issues.
The associated challenges with this approach includes the collaboration of the hospitals which can help in clinical trials for treatment of diseases. The confidentiality of the research plan is required to be maintained while working in the hospitals. The hospitals protocols are required to be followed while conducting research.
All of the following statement concerning oogenesis is true except
A. At the time of birth the ovaries contain only primary oocytes.
B. Ova develop from stem cells called oogonia.
C. An ovum will only complete meiosis if it is fertilized.
D. Oogenesis occurs continuously from puberty until menopause.
E. The first meiotic division is completed just prior to ovulation.
Answer:
The best answer to the question: All of the following statements concerning oogenesis are true, except:___, would be, D: Oogenesis occurs continuously from puberty until menopause.
Explanation:
The reason for this one being the right choice to answer the question is that in reality, females are born with their oocytes completed and this process of renovation of ova does not happen. The female is born with the primary oocytes complete and ready, and they will continue their process of maturation once the female reaches puberty. So it is not true that oogenesis happens from puberty until menopause and this is why D is incorrect. It is this the reason why females only have until a certain age for reproduction through natural methods. After a certain age, especially when menopause takes place, women do not ovulate anymore.
Statement D is incorrect. Oogenesis is the process from which primary oocytes develop. It happens in a cyclical manner with typically one ovum being released each menstrual cycle, not continuously throughout a woman's reproductive years.
Explanation:All of the statements A, B, C, and E concerning oogenesis are correct. Statement D, 'Oogenesis occurs continuously from puberty until menopause', is not true. Oogenesis does not occur continuously, it happens in a cyclical manner with typically one ovum being released each menstrual cycle, not continuously throughout the duration of a woman's reproductive years from puberty to menopause. Oogenesis is the process in which primary oocytes (A) grow and develop. These primary oocytes, which are present at the time of a female's birth, originate from stem cells called oogonia (B). An ovum will only complete meiosis if it is fertilized (C), and the first meiotic division is completed just prior to ovulation (E), creating a secondary oocyte and a polar body.
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after having the bone marrow biopsy which sleeping position is
required?
Answer:
If you had local anesthesia, you'll have to lie on your back for 10 to 15 minutes and apply pressure to the biopsy site.
Explanation:
Describe the visceral pleura, parietal pleura and pleural cavity.
Answer:
Visceral pleura: membrane that is in direct contact with the lungs
Parietal Pleura: membrane that is in direct contact with the inner part of the rib cage
Pleural Cavity: Space in between visceral and parietal pleura
Explanation:
The pleura is a membrane that covers the lungs, the mediastinum and the diaphragm, it divides in parietal and visceral. The parietal pleura is the external membrane that surrounds the inner part of the rib cage at the level of the lungs, lining also part of the diaphragm and the mediastinum. When the parietal pleura extends inwards enveloping the lungs it becomes the visceral pleura. These membranes protect the lungs and in between them there is a fluid filled space (pleural cavity) that cushions the respiratory movements, among other functions.
The secretion of of hormone A causes an increase in activity X in an organism. If this mechanism works by positive feedback, which of the following statements represents that fact?
A. An increase in X produces an increase in A
B. An increase in X produces a decrease in A
C. A increase in A produces an increase in X.
D. A decrease in A produces an increase in X.
E. Both A and C are correct.
Answer:
E. is the correct answer
Explanation:
C. An increase in A produces an increase in X.
This statement can be directly concluded from the description of the effects of hormone A on the activity of X in the problem.
A. An increase in X produces an increase in A
This statement can be concluded from the fact that A and X work in a positive feedback mechanism.
In a positive feedback mechanism, a stimulus produces a response (secretion of hormone A) which has an effect (increase in X) that increases the original stimulus. A cycle is created, in which secretion of A causes an increase of X, and the increase of X causes an increased secretion of A.
To shut off the positive feedback cycle, an outside factor is required.
Do you believe it is ethical to prescribe expensive drugs to
less wealthy patients, even if the drug is better quality than
cheaper drugs?
Answer:
When talking about medical ethics, the first thing that must be taken into account is that there are four major basic principles that direct medical practice, and in general, the practice of all healthcare professionals. These are: autonomy, justice, beneficence and non-maleficence. These four are the core principles that ensure that a doctor will always do the best he can in regards to the patient, and for the benefit of the patient.
Unfortunately, these principles do not always apply to the pharmaceutical industry, whose ideas are set more on making profit, while at the same time procuring chemical compounds that benefit the health of patients. However, they do not take into consideration the means a patient may, or may not have, to acquire the elements.
In the case of the doctor, however, this is another matter altogether as he must seek to do what is best for the patient, given the four major principles of medical ethics. In particular, the doctor must apply here, in this case, the principles of beneficence and non-maleficence and he must prescribe the expensive drugs to a patient who have less means if he considers that they are absolutely the best for the health of the patient, and that there is absolutely no other choice when looking at pharmaceutical options. He must first evaluate if a cheaper medication could not achieve the same results, and benefit both the health situation, and income situation, of the patient. If these two are considered, and the answer is: there are no other possibilities, then I say it is ethical. If the decision is taken based on anything other than the benefit of the patient, then, it would be absolutely unethical.
The space between the gingiva and the tooth that is not attached to the tooth is cafled
A. Alveolar bone
B. Sulcus
C. Periodontal ligament
D. Gingival margin
Answer: B. Sulcus
Explanation:
The gingival sulcus is the potential space that forms between a tooth and the enclosing gingival tissue. The depth of the gingival sulcus can be bounded apically by the gingival fibers and at the coronal end by the gingival margin.