Testis – male gonads – Epididymis - structure in the male reproductive system in which sperm fully mature and are stored – Sperm is produced in the seminiferous tubules vas deferens - tube that carries sperm from the epididymis to the urethra Prostate gland – large gland that secretes semen directly into the urethra Urethra - tube through which urine and semen are released from the body Penis - external male reproductive organ that connects the urethra to the outside of the body Spermatogenesis – the meiotic process of sperm production
The main structures of the female reproductive system are the – Ovaries – where meiosis occurs – Fallopian tubes (oviduct) – where fertilization occurs; after ovulation the egg moves through the oviduct to the uterus – Uterus – where the blastula stage of the embryo will implant and develop during the 9 month gestation – Vagina – birth canal – Cervix – mouth of the uterus – Endometrium – lining of the uterus – In addition to producing eggs, the female reproductive system prepares the female’s body to nourish a developing embryo.
Female Reproductive System Follicle - cluster of cells surrounding a single egg in the human female reproductive system Ovulation - process in which an egg is released from the ovary
Menstrual Cycle Human females release a gamete (egg) about every 28 days from puberty to menopause Follicular Phase – follicles in ovaries grow in response to FSH release from pituitary gland –Increasing amount of estrogen released Ovulation –Secondary oocyte ruptures out of the ovaries in response to an increase of luteinizing hormone (LH) from anterior pituitary gland. (about 14 days after menstruation) Luteal Phase –After ovulation the Corpus Luteum secretes estrogen and progesterone that thicken the endometrium Menstruation –If implantation of the embryo does not occur the buildup of the lining is shed. This is commonly called the period
Menstrual Cycle Follicular Phase – follicles in ovaries grow in response to FSH release from pituitary gland –Increasing amount of estrogen released Ovulation –Secondary oocyte ruptures out of the ovaries in response to an increase of luteinizing hormone (LH) from anterior pituitary gland. (about 14 days after menstruation) Luteal Phase –After ovulation the Corpus Luteum secretes estrogen and progesterone that thicken the endometrium Menstruation –If implantation of the embryo does not occur the buildup of the lining is shed. This is commonly called the period
Fertilization and Development Monoploid (n) Egg is Released Fertilization – Usually occurs in the upper region of the fallopian tube –Zygote – a fertilized egg Cleavage – rapid mitotic divisions which occurs after fertilization –Zygote Morula Blastula Implantation – Usually occurs 6 to 7 days after fertilization. – Blastula undergoes gastrulation Gastrula Gastrulation - process of cell migration by which a third layer of cells is formed within the cavity of a blastocyst
Endocrine System Regulatory System –separate, but works together with the Nervous System to: Maintain Homeostasis
Endocrine System and Nervous System Endocrine –Secretes hormones. Nervous –Secretes neurotransmitters In one case: –Epinephrine (adrenaline) – works for both systems Endocrine – Fight or Flight hormone released by adrenal gland Nervous – neurotransmitter which relays messages from one neuron another neuron
Hormones (chemicals) Chemicals that travel through the bloodstream and affect the activities of other cells Travel through blood target cell, tissue, organ –Can produce either: immediate, short-lived response –epinephrine Dramatic, long-term development or an entire organism –Metamorphosis
Hypothalamus Bridge between the Endocrine and Nervous systems –Nervous System Fight-or-Flight – sends electrical signals (impulses) adrenal gland epinephrine –Endocrine Produces oxytocin and antidiuretic homone Stores it in pituitory gland
Feedback Mechanisms Self- regulating mechanism that increases or decreases an action or the level of a particular substance Positive Feedback – labor –Contractions begin baby head to uterine opening more contraction more pressure Negative Feedback –Thyroxin levels in blood Hypothalamus TSH stimulates thyroid thyoxin hypothalamus stop making TSH
Excretory System Aids in the removal of waste materials –Skin –Lungs –Kidneys
The kidney Maintains homeostasis by controlling pH, water levels, blood volume, and waste materials Ureter – tube which carries urine to the urinary bladder. Nephron – functional unit of the kidney (about 1 million in each kidney) – Glomerulus – small network of capillaries encased in the upper end of the nephron by a cup- shaped structure called Bowman’s capsul – Loop of Henle – section of the nephron tubule where water is conserved, minimizing the amount of urine.
The skeleton supports the body, protects internal organs, provides for movement, stores mineral reserves, and provides a site for blood cell formation.
Bone Structure Periosteum - tough layer of connective tissue surrounding a bone Haversian canal - one of a network of tubes running through compact bone that contains blood vessels and nerves bone marrow - soft tissue inside cavities within bones; two types are yellow marrow and red marrow
Bone Formation Cartilage - strong connective tissue that supports the body and is softer and more flexible than bone Ossification - process of bone formation, during which cartilage is replaced by bone –Osteoblast – Helps to form bone –Osteocyte – Helps to maintain bone –Osteoclast – Helps to breakdown bone
Joints Joint - place where one bone attaches to another Depending on its type of movement, a joint is classified as: –Immovable Joints - fused together (skull) –Slightly Movable Joints – vertebrae; tibia, fibula –Freely Movable Joints
Integumentary System The integumentary system serves as a barrier against infection and injury, helps to regulate body temperature, removes waste products from the body, and provides protection against ultraviolet radiation from the sun.
Skin Formation Epidermis - outer layer of the skin, formed by epithelial cells –The outer layer of the epidermis is formed of dead, flattened cells that have been toughened by keratin –The inner layer of the epidermis forms new cells and those cells are pushed up to the surface of the epidermis Keratin - tough, fibrous protein found in skin Melanin - dark-brown pigment found in skin
Skin Epidermis - outer layer of the skin Dermis - innermost layer of the skin –collagen fibers, blood vessels, nerve endings, glands, sense organs, smooth muscles, and hair follicles – Sweat Gland, Sebaceous Glands Subcutaneous Layer – formed by a loose connective tissue called adipose (fat)
Hair and Nails Hair – functions: protection form UV rays, insulation, protection (dead keratin filled cells) hair follicle - tubelike pocket of epidermal cells that extends into the dermis; cells at the base of hair follicles produce hair Nails – form in a similar process as skin. Keratin helps to harden nails