Obalectures

Continuation Joints of the Pelvis Recall that a joint as the name suggests is a meeting point or an articulation of two bones. The bony pelvis has four major joints as follows: Lumbosacral joint Sacrococcygeal joint Sacroiliac joint Pubic symphysis (or symphysis pubis) Lumbosacral joint It is a cartilaginous joint between the fifth lumbar vertebrae (L5) and the sacrum. This joint allows flexion, extension and minimal lateral rotation Sacrococcygeal joint It is an articulation between the apex of the sacrum and the base of the coccyx. It is slightly mobile allowing limited degree of flexion and extension. It is even more mobile in the female. This mobility increases the anteroposterior diameter of the pelvis during labour and defecation. It is a cartilaginous joint. Sacroiliac joint The sacroiliac joint is a synovial joint formed by the auricular surface of the sacrum and the ilium of the hipbones. There are right and left sacroiliac joints. These joints allow very little to no movement

By Oba Mike Introduction Connective tissues are the most abundant tissues in the body. As the name suggests, the major function of connective tissue is to bind together, support and strengthen cells and other body tissues. Functions of Connective tissues 1. They give structural and functional support to cells and other tissues. 2. Protection and defense against pathogens. 3. Stores energy. 4. Transport of substances within the body. 5. Insulation. Structure of Connective Tissues Connective tissues consist of two basic elements: 1. Cells 2. Extracellular matrix Cells Connective tissue cells originate from embryonic cells called mesenchyme . The cells vary according to the type of tissue and include the following: A. Fibroblasts B. Adipocytes (fat cells) C. Macrophages D. Mast cells E. Blood cells ( erythrocytes, leukocytes, thrombocytes). Fibroblasts They are large flat cells with branching processes. They are the most numerous connective tissue cells and are present in all the general

By Oba Mike NOTE: This note goes with the slides. There are clearer pictures in the slide for you to view and draw. Introduction A tissue is a group of cells that function together to carry out specialized activities. Cells of a particular tissue usually have a common embryonic origin. The structure and functioning of a tissue are influenced by factors such as: i.  The nature of the extracellular material that surrounds the tissue cells. ii. The connections between the cells that compose the tissue. Tissues exist in different forms, hard e.g bone, semisolid e.g fat, liquid e.g blood. The branch of anatomy that deals exclusively with the study of tissues is termed histology . Pathology is the branch of medicine concerned with diseases of cells and tissues. Types of tissues Body tissues can be classified into four types according to their structure and function: 1. Epithelial tissues 2. Connective tissues 3. Muscular tissues 4. Nervous tissues For now, we will focus only on epithelial a

By Oba Mike Introduction Spermatogenesis is the formation of spermatozoa (sing. Spermatozoon) in the seminiferous tubules of the testis. It takes place during the reproductive period, which begins at the age of puberty (12-16years) and continues even to old age. Location It occurs in the seminiferous tubules of the testis. Duration 64 - 74 days Stages Spermatogenesis can be divided into three stages: 1. Spermatocytosis 2. Meiosis 3. Spermiogenesis Spermatocytosis Spermatocytosis is the conversion of a spermatogonium (stem cell) into primary spermatocyte . It marks the beginning of spermatogenesis. Spermatogonia are stem cells located in the walls of the seminiferous tubules near the basement membrane. These cells are similar to oogonia in the ovary and arise from primordial germ cells that migrated from the yolk sac.  Each spermatogonium is diploid and contains 46 chromosomes (44+X+Y) . Prior to the division into primary spermatocyte, the spermatogonium first divides into type A and t

By Oba Mike Image credit: sites.google. com Introduction The bony pelvis or simply pelvis is a basin-like structure composed of the hip bones, pubic symphysis, sacrum and coccyx. Functionally, the pelvis provides support to the vertebral column, pelvic and lower abdominal organs. It also connects the bones of the lower limbs to the axial skeleton. Functions of the Pelvis 1. Supports the vertebral column. 2. Protects pelvic and lower abdominal organs. 3. Connects the bones of the lower limbs to the axial skeleton. 4. Transmits the weight of the body to the lower limbs while standing and to the seat while sitting. 5. Helps in the attachment of several muscles. 6. Supports childbearing in females. Components of the Bony Pelvis The bony pelvis is formed by four different structures: 1. 2 hip bones (pelvic girdle) 2. Pubic symphysis  3. Sacrum 4. Coccyx Hip bones The hip bones also called pelvic or coxal bones are the two bones that form the pelvic girdle. They form the anterior and latera

By Oba Mike INTRODUCTION During their reproductive years (which begins from puberty), nonpregnant females normally exibit cyclical changes in the ovaries and uterus. These changes begin from menarche and terminates at menopause .  Each cycle takes about a month and involves both oogenesis and preparation of the uterus to receive the fertilized ovum. The changes that occur in the ovaries, form the ovarian cycle while the changes that occur in the uterus form the uterine or menstrual cycle. Both cycles are regulated by hormones secreted by the hypothalamus, anterior pituitary and ovaries. DURATION Both cycles take an average of 28 days. Some females have longer duration while others experience shorter duration. However, for descriptive purpose, we'll focus on a regular 28 day cycle. OVARIAN CYCLE Ovarian cycle above The ovarian cycle comprises the series of monthly changes that occur in the ovaries during the reproductive years of a nonpregnant woman. These changes can be grouped

Instructions Choose the  correct options and type appropriately in the comment section. No multiple entry.  If you wish to change your answer, delete the comment and retype. Goodluck. 1. The functional difference between the Ureter and Urethra is that? A. The ureter comes before the urethra. B. The urethra is longer than the ureter. C. The ureter drains the kidney while the urethra drains the bladder. D. The ureter is paired while the urethra is single. 2. In terms of location, the kidneys are? A. Retroperitoneal B. Bean shaped C. Pyramidal D. Abdomino-pelvic 3. The kidneys are paired structures situated in? A. Posterior Abdominal wall B. Anterior Abdominal wall C. Abdominal cavity D. Pelvic cavity. 4. Which of the following statements is incorrect? A. An increase in blood volume decreases blood pressure. B. An increase in blood volume inhibits renin secretion. C. Macula densa cells form part of the Juxtaglomerular apparatus (JGA). D. The parenchyma is formed by the renal cortex and py

By Oba Mike  Image credit: courses.lumenlearning.com Introduction Sexual reproduction is the process by which organisms produce offspring by making germ cells called gametes. The male gamete (sperm cell or spermatozoon) then unites with the female gamete (egg cell or ovum or secondary oocyte) through a process called fertilization to form a single cell called zygote that begins to grow through cleavage (cell division). Unlike other systems, the reproductive system is different in males and females both structurally and functionally. Study of the male reproductive system and the diseases that affect it is termed Urology . Organs of the Male Reproductive System The organs are grouped into: 1. Testis (main sex gland) 2. Ducts (epididymis, vas deferens, ejaculatory duct and urethra) 3. Accessory sex glands (seminal vesicle, prostate, and bulbourethral gland) 5. Supporting structures (scrotum, penis, and spermatic cord). The organs can also be grouped into e