By V. Dargoth. McPherson College.
Following ovulation order yasmin 3.03mg fast delivery, the granulosa cells of the empty follicle luteinize and transform into the progesterone-producing corpus luteum purchase yasmin 3.03 mg without prescription. The ovulated oocyte with its surrounding granulosa cells is picked up by the infundibulum of the uterine tube, and beating cilia help to transport it through the tube toward the uterus. The endometrium responds to estrogen released by the follicles during the menstrual cycle and grows thicker with an increase in blood vessels in preparation for pregnancy. If the egg is not fertilized, no signal is sent to extend the life of the corpus luteum, and it degrades, stopping progesterone production. This decline in progesterone results in the sloughing of the inner portion of the endometrium in a process called menses, or menstruation. The breasts are accessory sexual organs that are utilized after the birth of a child to produce milk in a process called lactation. Testosterone produced by Leydig cells in the embryonic testis stimulates the development of male sexual organs. Whereas the gonads and some other reproductive tissues are considered bipotential, the tissue that forms the internal reproductive structures stems from ducts that will develop into only male (Wolffian) or female (Müllerian) structures. To be able to reproduce as an adult, one of these systems must develop properly and the other must degrade. These changes lead to increases in either estrogen or testosterone, in female and male adolescents, respectively. Increases in sex steroid hormones also lead to the development of secondary sex characteristics such as breast development in girls and facial hair and larynx growth in boys. What specialized structures help guide the oocyte This interrupts the path taken by sperm through the ductus from the ovary into the uterine tube? What would likely occur if the cilia were spermpath) to explore the structures of the male paralyzed at the time of ovulation? A baby’s gender is determined at conception, and the the testes and ends as the sperm leave the penis through different genitalia of male and female fetuses develop from the urethra. Endometriosis is a disorder in which endometrial cells not in somatic cells, and how do these specializations implant and proliferate outside of the uterus—in the uterine function? Explain how these changes lead to the up muscles, they can also affect testosterone production in increases of sex steroid hormone secretions that drive many the testis. Explain how the internal female and male reproductive the testis if a male takes large amounts of synthetic structures develop from two different duct systems. The dramatic changes of fertilization, embryonic development, and fetal development are followed by remarkable adaptations of the newborn to life outside the womb. An offspring’s normal development depends upon the appropriate synthesis of structural and functional proteins. This, in turn, is governed by the genetic material inherited from the parental egg and sperm, as well as environmental factors. Because each of these reproductive cells is a haploid cell containing half of the genetic material needed to form a human being, their combination forms a diploid cell. This new single cell, called a zygote, contains all of the genetic material needed to form a human—half from the mother and half from the father. Almost immediately, millions of these sperm are overcome by the acidity of the vagina (approximately pH 3. Thus, the race into the uterine tubes, which is the most typical site for sperm to encounter the oocyte, is reduced to a few thousand contenders. Their journey—thought to be facilitated by uterine contractions—usually takes from 30 minutes to 2 hours. If the sperm do not encounter an oocyte immediately, they can survive in the uterine tubes for another 3–5 days. In comparison, an oocyte can survive independently for only approximately 24 hours following ovulation. During the journey, fluids in the female reproductive tract prepare the sperm for fertilization through a process called capacitation, or priming. They also deplete cholesterol molecules embedded in the membrane of the head of the sperm, thinning the membrane in such a way that will help facilitate the release of the lysosomal (digestive) enzymes needed for the sperm to penetrate the oocyte’s exterior once contact is made. Sperm must undergo the process of capacitation in order to have the “capacity” to fertilize an oocyte. If they reach the oocyte before capacitation is complete, they will be unable to penetrate the oocyte’s thick outer layer of cells. Contact Between Sperm and Oocyte Upon ovulation, the oocyte released by the ovary is swept into—and along—the uterine tube. Fertilization must occur in the distal uterine tube because an unfertilized oocyte cannot survive the 72-hour journey to the uterus. As you will recall from your study of the oogenesis, this oocyte (specifically a secondary oocyte) is surrounded by two protective layers. The corona radiata is an outer layer of follicular (granulosa) cells that form around a developing oocyte in the ovary and remain with it upon ovulation. The underlying zona pellucida (pellucid = “transparent”) is a transparent, but thick, glycoprotein membrane that surrounds the cell’s plasma membrane. As it is swept along the distal uterine tube, the oocyte encounters the surviving capacitated sperm, which stream toward it in response to chemical attractants released by the cells of the corona radiata.
Excitability and parameters of the stimulus A stimulus must fulfill to evoke response generic 3.03mg yasmin free shipping. Neuromuscular junction / synapse The neuromuscular junction is the specialized region of contact between nerve and muscle 3.03 mg yasmin overnight delivery. Each skeletal muscle fiber receives only one of the many terminal branches of the nerve fiber. All movements are composites of contraction of muscle unit, the motor neuron, its axon, and all the muscle fibers it innervates. The resulting contraction of each muscle fiber of the motor unit is all –or- nothing. Increase in the strength of muscle contractions are obtained through the recruitment of greater number of motor units. Motor unit: is the motor nerve and all the muscle(s) innervated by the nerve Functional anatomy of neuromuscular Junction Presynaptic Structure The axon terminals in knobs on the membrane surface do not fuse with it. There are active zones of the presynaptic membrane, where transmitter 75 release occurs. The presynaptic membranes have selective ionic gates, voltage gated ++ Ca channels The synaptic Cleft: The cleft is a gap of about 40 mm separating the axon terminal and the muscle membrane. Postsynaptic Structure At the junction area, there is an enlargement of the sarcoplasm of the muscle fiber, known as the end plate. The postsynaptic membrane is both structurally and physiologically different from the rest of the muscle membrane. The region of the muscle surface membrane under the nerve terminal is sensitive to acetylcholine. Recycling of vesicles: The disrupted vesicles are modified and same vesicles are pinched off and filled. The Ach receptor is a protein; its conformation changes when Ach binds to it, resulting in the opening of the ionic gates and a change in permeability. Curare also binds to receptor protein but alters it to an inactive form, which does not result in depolarization. Snake venom containing bungarotoxin binds very tightly and specifically to Ach receptor. The receptor 7 4 density is very high (3x 10 ) per end plate, which is enough for the 10 quanta of Ach released. Inactivation of acetylcholine The concentration of Ach at the end plate remains high briefly for it is hydrolyzed rapidly by the enzyme AchE into choline and acetate. Synapse and neuronal integration A neurotransmitter transmits the signal across a synapse. Classically, a neuron to neuron synapse is a junction between an axon terminal of one neuron and the dendrites or cell body of a second neuron. Inhibitory and excitatory synapses Some synapses excite the post synaptic neuron whereas others inhibit it, so there are 2 types of synapses depending on the permeability changes in the post synaptic neuron by the binding of neurotransmitter with receptor site. At an excitatory synapse, the neurotransmitter receptor combination opens sodium and potassium channels within the subsynaptic membrane, increasing permeability to both ions. Removal of neurotransmitter It is important that neurotransmitter be inactivated or removed after it has produced desired response in the postsynaptic neuron, leaving it ready to receive additional message from the same or other neuron inputs. The neurotransmitter may diffuse away from the cleft, be inactivated by specific enzyme within the subsynaptic membrane, or be actively taken back up in to the axon terminal by transport mechanism in the presynaptic neuron for storage and release at another time. Characteristics of chemical transmission • Chemical transmission is unidirectional • Chemical transmission is graded, with the amount of transmission chemical released dependent on the frequency of stimulation of the presynaptic neuron. The muscle cells are the real specialists having contractile proteins present in skeletal, cardiac and smooth muscle cells. They are capable of shortening and developing tension that enables them to produce movement and do work. Skeletal muscle is the largest body tissue accounting for almost 40% of the body weight in men and 32% in women. Muscles are categorized as striated and non-striated/ smooth muscles and also typed as voluntary and involuntary subject to innervations by somatic or autonomic nerves and whether subject to voluntary or not subject to voluntary control. Microstructure of Skeletal muscle Skeletal muscles contract in response to signals from its innervating somatic nerve that releases acetylcholine at its terminals that starts the muscle action potentials. A muscle fiber is fairly large, elongated and cylindrical shaped ranging from 10-100 μm in diameter and up to 2. A muscle is made up of a number of muscle fibers arranged parallel to each other and wrapped by connective tissue as a bundle. A single muscle cell is multi-nucleatd with abundant number of mitochondria to meet its high energy demands. Each cell has numerous contractile myofibrils, constituting about 80% of volume of muscle fibers extending the entire length. Each myofibril consists of the 81 thick myosin filaments (12-18 nm diameter) and thin actin filaments (1.
Though many hypolipidemic drugs are commercially available to control the cholesterol levels generic 3.03 mg yasmin with mastercard, they often elicit harmful side effects discount yasmin 3.03mg on-line. Nucleic acids are present both in the free state as well as conjucated with proteins (Nucleoproteins). Deoxyribonucleic acid Structural Components of Nucleic acids Components Ribonucleic acid Deoxyribonucleic acid Acid Phosphoric acid Phosphoric acid Pentose Sugar D-ribose D-2 deoxy ribose Nitrogen Bases i. It contains 3 monovalent 3 4 hydroxyl groups and a divalent oxygen atom, all linked to a pentavalent phosphorus atom. One possesses D-2-deoxyribose, (deoxyribonucleic acid) while the other contains D-ribose (hence called ribonucleic 89 acid). Purine Bases These are all derived from their parent compound purine, which contains a six membered pyrimidine ring fused to the 5 membered imidazole ring, the purine derivatives found in nucleic acids are adenine and guanine. They are 5 methylcytosine, N4 acetyl cytosine, N6 methyladenine, N6, N6 dimethyladenine and pseudouracil etc. This enzyme catalyses the polymerization of mononucleotides to 91 polynucleotides, which needs the following for its action. A template strand dictates the synthesis of the new daughter strand and sequence of the template strand determines the addition of the nucleotides. The results show that they form bands with intermediate density alone in the frst generation, which confrms the semiconservative model of replication. Exonucleases are the nucleases that attack only the internucleotide bonds located at the ends of the nucleic acid. Endonucleases are the nucleases that attack only the internucleotide bonds located throughout the length of the nucleic acid chain (in the middle). Nucleotidases (Phosphatases) These enzymes hydrolyse the nucleotides to the corresponding nucleosides and inorganic phosphate molecules. Phosphatase Nucleotides Nucleoside + Phosphate Nucleosidases (Nucleoside phosphorylase) The nucleosides obtained above either absorbed or degraded into bases and sugars by nucleosidases. Mechanism Transcription involves 3 stages i) Initiation ii) Elongation iii) Termination Three phases of transcription 1. This complex enzyme, called the holoenzyme is needed to initiate transcription since the s factor is essential for recognition of the promoter. It is common for prokaryotes to have several s factors that recognize different types of promoter (in E. The holoenzyme binds to a promoter region about 40-60 bp in size and then initiates transcription a short distance downstream (i. With in the promoter lie two 6 bp sequences that are particularly important for promoter function and which are therefore highly conserved between species. Using the convention of calling the frst nucleotide of a transcribed sequence as +1, there 2 promoter elements 98 lie at position -10 and -35, that is about 10 and 35 bp respectively, downstream of where transcription will begin. The most common termination signal is a G ≡ C rich region is a palindrome, followed by an A = T rich sequence. Those that lack such a structure require an additional protein, called rho protein (r) to help recognize the termination site and stop transcription. The product of transcription in eukarryotes are called as primary transcripts and they undergo modifcation by a process called post transcriptional modifcation. Okasaki fragments are present in i) both the parental strands ii) both the daughter strands iii) leading strand iv) lagging strand c. G-C rich region followed by A-T rich region is a signal for i) initiation ii) elongation iii) termination iv) primer formation d. One among the following is not a modifed base i) pseudo uridine ii) isopentyl adenine iii) methyl guanosine iv) deoxy thymine e. The metabolism of our body comprises two major balanced activities: anabolism (synthesis) and catabolism (degradation). Whether the metabolic changes are exergonic or endergonic, most of them have to be catalysed by enzymes. If one particular enzyme is defcient or absent then that leads to a block in the pathway of biochemical reactions leading to metabolic abnormalities which are present throughout the life and handed over to the progeny. The absence or defciency of an enzyme will cause an abnormal accumulation of the intermediate products of metabolism in the body and increased excretion in urine as such or their degradation products. For example, in the following reaction a c b d R B C D P R is the reactant, B, C and D are intermediates and P is the product and a, b, c and d are enzymes catalyzing various steps of the reactions. In this reaction pathway, if any one of the enzyme is defcient or absent, the previous intermediate accumulates and produces toxicity. It also affects the amount of product (P) formation which may be essential biologically and there by leads to pathological diseases. Beadle and Tatum put forth their theory of one gene one enzyme hypothesis which states that one gene controls the synthesis of a single enzyme.
The density of house dust mite allergens can be assessed by a test cheap 3.03 mg yasmin mastercard, which measures the concentration of mite excreta in dust generic yasmin 3.03 mg without a prescription. Mites and associated fungi can be controlled by decreasing the humidity in rooms, improving ventilation and removing dust. Bedrooms and living rooms should be aired regularly, or other measures should be taken to reduce dampness. The shaking of bedclothes and frequent washing of sheets and blankets reduce the availability of food and therefore the number of mites. General insecticides used for pest control are not effective but a special product containing benzyl benzoate is available, which destroys mites when applied to mattresses, and upholstery. Leishmaniasis Leishmaniasis is a term used to describe a number of closely related diseases caused by several distinct species, subspecies and strains of leishmania parasites. The epidemiology of leishmaniasis is complex, involving not only different parasite species but also strains of parasites. The epidemiology of this disease is largely determined by: o The species of sandflies, their ecology and behavior; o The availability of a wide range of hosts; 141 o The species and strains of leishmania parasites. It is characterized by typical ulcer that starts as a nodule at the site of bite, and then a crust develops in the middle followed by ulcer. Case treatment Simple cutaneous leishmaniasis usually heals without treatment and renders the person immune to other infections with the same parasite species. It is recommended that personal protection measures be taken, such as repellents, fine mesh screens, insecticide treated clothing and/ or insecticide-treated bednets are used. Application of basic sanitation This is aimed at abolishing the breeding sites around human habitation, such as proper disposal of refuse and rubbish heaps; filling of cracks and holes in the soils and walls. Control of Animal Reservoir In Ethiopia, control measures were carried out against the rock hyrax, a wild animal reservoir of leishmaniasis, where by reduction of the prevalence of leishmaniasis has occurred. Therefore, it is essential to become familiar with foods that heal, vegetable juices, and fats that heal, unrefined sea salts. Psychophysical activities will help you balance your body and will help you relief accumulated stress. Atopic refers to a group of diseases where there is often an inherited tendency to develop other allergic conditions, such as asthma and hay fever. This module is intended to be used by health extension workers and is believed to provide them with basic information that is not included in the core module. However, it is essential to undertake the management, prevention and control activities on common skin infections. Directions for using the module ¾ Prior to reading this satellite module please be sure that you have completed the pretest and studied the core module. In the community, those patient who develop bed sore as a result of chronic illness, can be well managed by health worker through a) Frequent changing position b) Providing bed bath and back care c) Not allow to eat that much vitamin and protein until the wound is healed d) All except C e) None of the 6. As being the health worker of the community, all activity has to be carried out respect to leprosy disease patient except: a) Teach the patient about disease b) Avoid any discrimination and stigmatization from the community c) Treat any skin reaction that occurred from disease process d) Teach the patient, on how to protect his/her wound form danger e) None of the above 146 8. Which of the following is the role of health worker who is dealing with a patients having wound secondary to accident? Scabies is a disease caused by an arthropod called scabies mite; therefore it is not acquired by close contact with an infected individual. General objective The general objective of this module is to equip health extension workers with the knowledge and skills needed to deal with the management, prevention and control of common skin diseases. Specific objectives After complete reading of this module, health extension workers will be able to: ¾ Describe common skin infections ¾ Explain the management of common skin infections ¾ Mention important prevention and control measures ¾ Portray the significance of hygienic behavior in the mitigation of common skin disease. The skin and its parts The major components of the system are the following: ¾ Skin ¾ Hair ¾ Nails These components not only reflect person’s general health status, they also serve as indicators of more general disturbances. The Skin ¾ The skin is the boundary between ourselves (the internal organs) & what is around us) ¾ It reflects internal changes and reacts to changes in the environment ¾ It is composed of tissue that: - Grows - Differentiates & - Renews itself The entire layer of the epidermis is replaced about every 15 to 30 days, depending on its location. Causes: - Streptococcus - Staphylococcus ¾ Although impetigo is seen at all ages, it is particularly common in children living in poor hygienic condition. Treatment: ¾ Systemic antibiotic therapy ¾ Antiseptic to clean the skin ¾ Wash hand frequently ¾ Avoid scratching ¾ Teach the patient ¾ Arrange follow up 7. Treatment: - o Promote skin care & don’t scratch o Encourage rest so that the infection remains localized o Give anti pain and analgesic o Send to health facility for parentral treatment 149 7. Frunclosis (Boil): Is an acute inflammation arising deep in one or more hair follicles and spreading in to surrounding dermis. It is the deeper form of folliculitis ¾ Furuncles may occur any where on the body but are more prevalent at areas where irritation and pressure, friction, perspiration such as the back of the neck, the axially buttock. Carbuncle Is an abscess of skin and subcutaneous tissue representing an extension of furuncle that has invaded several hair follicles and is larger and deeper. Treatment: Do not squeeze Warm and moist compresses increases visualization and hasten resolution. Leprosy (Hanson’s Disease) It is a chronic bacterial infectious disease caused by bacteria called mycobacterium leprae and which can affect skin, peripheral nerves and other organs like respiratory tract and eyes.
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