Bms2011 Mid Sem

Phlyum of carnivorous animals that sting. Radially symmetrical. Diploblastic. Sesile polyp or mobile medusa. Hydrostatic skeleton for digestion

Phylum that diverged from cnidarians. Tripoblastic and bilateral symmetry. Diverges into Protostomes and Deuterostomes

Acts as a fluid filled body cavity. Functions: circulate/store metabolites, provides a cushioned space for organs, increases size without more cells, hydrostatic skeleton.

Body cavity fully lined by mesoderm e.g humans, segmented worm

Body cavity where the outer wall is lined by mesoderm. E.g roundworms

Body cavity containing a non-split coelom. E.g flatworms

Diverged from cnidaria so are tripoblastic and have bilateral symmetry. Have radial cleavage. Anus develops first in the blastopore. pockets of mesoderm form.

Derived from bilateria/deuterostomes. They are bilaterally symmetrical and are tripoblastic(develop mesoderm and coelom). Spiral cleavage. Anus is formed second in the blastopore(mouth is formed first).

Marine animals that are sessile and slow moving (looks like an echidna). They have secondary bilateral symmetry(bilateral in embryo which resembles humans)

All animals after echinoderm. 4 characteristics: notochord, dorsal hollow nerve, pharyngeal slits, post-anal tail.

Phylum with a carnium/skull/eye structures/neural crest. e.g Myxini(hagfishes)

Have a backbone and paired appendages. Can be either an exo or endo skeleton. But lampreys lack the paired apdgs. e.g Petromyzontida(lampreys)

Jawed vertebrates. Derived from Pharyngeal slits. e.g sharks rays, chondrichthyes

Cartilagenous fishes. Skeleton predominantly cartilage. e.g shark, rays, chimaeras

Development of lungs/lung derivatives. Fins are supported by dermal rays and not muscle. e.g Actinopterygii (ray-finned fishes)

Have rod shaped bones. Muscles. Can now walk underwater. This is the first sign of limb development. e.g actinistia, lung fishes

Limbs! And a stronger vertebral column. Ribs neck and supporting girdles. e.g amphibia

produce an amniotic egg. have thicker skin(keratin). e.g reptiles and birds. Diverged into reptillia and mammalia.

Defined by the existence of mammary glands producing milk and hair. Development of a larger brain and increased metabolism.

Multiregional: When Homo erectus left Africa 2 mya and dispersed into other portions of the Old World, regional populations slowly evolved into modern humans. Continuity with neanderthals.

Replacement/Out of Africa: 2 migrations out of africa. No continuity with neanderthals

Buffy coat(smallest layer, platelets and leukocytes), plasma(rises to the top), erythrocytes(RBC's, lowest layer)

RBC's are produced in the bone marrow. When they form they eject their nucleus and so cannot replicate because of their lack of DNA.

3 layered wall: tunica externa, tunica medica, tunica intima.

A complex sac of multiple layers that provides a space for the heart to move and contract . Consists of the fibrous pericardium(outer layer) and the serous pericardium(inner layer which secretes fluid for lubrication for movement by the heart).

Blood circulation through the liver. The function is to detoxify and metabolise. Takes oxygen poor nutrient rich blood from the GI tract to the liver via the portal vein.

Single celled wall lumen parallel to blood vessels which contains drained interstitial fluid. This checks on overall organism health(which may lead to an activated immune response).

This is the largest lymphatic organ located in the 2nd quadrant. Contains 2 pulps: white pulp(lymphocyte storage). Red pulp(reservoir for RBC's and platelets.

The Nasal Cavity and Pharynx.

Part of the URT. Consists of pseudo-stratified columnar epithelium, the nasal septum, external nares, conchae.

central wall of bone and cartilage that divides the nasal cavity

Nostrils, bilateral opening of the paranasal sinuses. When this is inflamed it blocks the passageway which can cause a headache

Bony plates and soft tissue found inside the nose. It increases surface area of mucous membranes for humidifying air and increasing temperature. Also important for directing the air to the olfactory bulb.

Funnel shaped common space used by both the respiratory and digestive tracts. Directs air to the larynx/bronchi and ingested food to the esophagus. Pharynx walls are lined with mucosa (stratified squamous epithelium) and skeletal muscle. There is the nasopharynx, oropharynx, laryngopharynx.

conducting airways: larynx, trachea, bronchi etc.

Cartilaginous structure that connects the pharynx to the trachea.

Cartilage which deflects food into the esophagus

Partial ring of cartilage: not complete so that esophagus doesn't rub against from the movement of swallowing.

Complete ring of cartilage

A flexible and slightly rigid tube with 15-20 cricoid cartilage rings. Trachea splits into 2 primary bronchi.

Cartilage is being replaced by smooth muscle leading to one cell thick alveoli

region where blood vessels enter/leave

Lines the surface of each lung

Lines the internal abdominal walls: thoracic walls, mediastinum, diaphragm

The space between the visceral and parietal pleura which contains pleura which is serous and secretes fluid. The fluid creates hydrostatic tension which supports the lungs.

Receives regular rhythmic signals from the ANS

Liver, gallbladder, pancreas

tongue, salivary glands, teeth

Largest salivary gland, which overlays the bottom teeth. *accidentally biting on your cheek bit, para(tid)aalysed. produce saliva (20%-30%)

Produce most of the saliva(60-70%) and are located inferior to the body of the mandible but the ducts open on either side of the tongue. It has many lymph nodes associated with it.

Assessory digestive organ made of skeletal muscle and lightly keratinised stratified squamous epithelium. Contains papillae and lingual tonsils.

made up of skeletal muscle(superior) and smooth muscle(inferior) and connects the pharynx to the stomach. undergoes peristalsis and segmentation.

Complex interconnections of neurons between the tunics. 2 types: Meissner's submucosal, Auerbach's(myentric)

Located in the submucosa layer of the GI tract, and regulates SECRETION

Located in the muscularis externus tunic layer of the GI tract and regulates MOTILITY

Lines the abdominal(body) cavity. Secretes peritoneal fluid and stores fat.

Lines the outer layer of the wall of the gut components

Organs that are suspended from the body wall by a mesentry. e.g stomach, transverse colon, Small intestine

Located inferior to the diaphragm. divided into the cardia, fundus, body and pylorus. It has large circular folds called rugae and 3 layers of smooth muscle.

Duodenum, Jejunum, Ileum. Absorbs most of the nutrients

1.5m long. absorbs most of the water, electrolyes and only some remaining nutrients.

Accessory digestive organ

Multiple Glomeruli merge all of their ducts together to form the mesonephric duct which drains into a region called the cloaca(receives urinary and digestive secretions) and becomes the gonads.

3rd type of kidney that has evolved over time. the urinary and reproductive tract are separate and then connect.

An expandable skeletal reservoir for urine made of 4 tunics. The ureter enters the bladder at a steep angle at the bottom, so it fills the bladder from the bottom up. A triangle shaped area at the bottom of the bladder called the trigone ensures that urine will flow down the urethra even when the bladder wall contracts, to ensure there is no back flow in the ureters.

Tube connecting the urinary bladder to the exterior containing a mucous lining secreted by urethral glands. Smooth muscle fibers surround the mucosa and help propel urine to the outside of the body.

only 3-5cm long because it only transmits urine from the bladder to vestibules

18-20cm long common passageway for both urine and semen. Prostatic urethra(3cm) --> membranous urethra(1cm)--> spongey urethra(15cm)

Gives rise to the 3 germ layers (endoderm, mesoderm, ectoderm). Germ(sex) cells differentiate separately.

Derived from intermediate mesoderm which later develops into the urogenital system.

The common gonad starts off as a bipotential gonad and then a transcription factor SRY found on the Y chromosome witches on a cascade of genes responsible for male gonad development. Testis development also requires DHT and AMH. For ovary development there must be the absence of the SRY gene but also must have 2X chromosomes and other factors.

Twin set of ducts and tubes formed within the first 10 weeks of development. Contains both The Mullerian(female) ducts and Wolffian ducts(male)

Duct in the bipotential reproductive system. In a female embryo it develops into the fallopian tubes, uterus and vagina. The wollfian ducts degenerate

Duct in the bipotential reproductive system. In a male embryo its develops into the vas deferens and prostate.

In females it stays the way it is. In males it develops as the scrotum, into which the testes will descend at birth.

The testes stay outside the body to stay cooler since the optimal temperature of some enzymes in spermatogenesis is lower than body temp. 34 deg.

A coiled tube (4-5m) along the side of the testis which acts a site of sperm storage and maturation(development of a tail).

Cremaster and Dartos

Before birth, it drives the development of the external genitalia, where the testes descend out from the frontal pelvis and into the scrotum. After birth, testosterone secretion ceases until puberty, where thereis a surge of testosterone. It eventually decreases but they produce it at high levels for most of their lives. This results in enlargement of testes, penisand scrotum, facial hair, pubic hair etc. Spermatogenesis begins at this pubescent stage.

Thick-walled tube consisting of muscle and fascial layers formed by the vas deferens, surrounding tissue, veins and arteries that runs from the deep inguinal ring in the abdominal wall down to each testicle.

Inferior to the prostate gland. Secretes a clear vicous mucin which protects the urethra and serves as a lubricant during sex.

Erection: Parasympathetic innervation - dilation

Emission: Movement of secretions from accessory glands which provide sperm with nourishment.
Ejaculation: Expulsion of semen out of the penis by the rhythmic contractions

(After gastrulation but before Gonad formation) Specification: Around 6 cells in the embryo express Blimp1 , which suppresses all genes that would've turned them into somatic type cells. Commitment: After several rounds of proliferation, a subset of the Blimp1 positive cells express Stella, and commit to the germline. The rest of the cells go off and become other tissues. Migration: PGCs undergo both passive and active migration to the gonads. Extensive proliferation occurs during this migration Colonisation: PGCs reach and colonise the gonad(week 6-8 of gestation), and undergo sex determination

Germ cells that enter the testis. They undergo mitosis-arrest-mitosis, and don't enter meiosis/spermatogenesis until puberty

Germ cells that enter the ovary. Entermeiosis but arrest at prophase I of meiosis until puberty (fertilisation bysperm)

Malignant tumour where thetestis will seem very disorganised

testicular cancer

1 oogonium --> 1 ovary + 3 polar bodies. There is only 1 because there is not enough material to produce 4 fully supplied ovaries. 1 ovary requires a large supply of nutrients for its first stages of development. The polar bodies to help direct early embryonic axes. The anterior posterior axis of the embryo is set up at the first cleavage division of the embryo.

1spermatogonium --> 4 spermatozoa(&

Crossing over of alleles, independent assortment, random fertilisation

primordial cell -> primary cell --> secondary cell (puberty)

Hormone needed for the survival of follicles and their continued maturation

Up to 50 oocytes will mature but only one will dominate (defined around 7 days prior to ovulation). Once the dominant follicle enlarges, it becomes FSH independent, and secretes high levels of inhibin. The inhibin suppresses pituitary FSH production, causing the remaining 49 semi-matured follicles to degenerate and die.

spermatogonium start in the coiled seminiferous tubules --> 2 rounds of meoisis --> spermatozoa in the inner layer. Supported by leydig, sertoli and immune cells.

Testosterone producing cells between the tubules in the testes.

'Nurse cells' that extend from the basement membrane to the lumen which express the SRY gene and keep the germ cells that start the process healthy and nourished.

Males: social structures, seduction or dominance, mate guarding.
Females: territorality, sexual signals, subtle and complex social behaviour, alliance formation(wingman), fashion and exhibition of figure, mate guarding.

Composed of 206 bones:
Axial skeleton: 80 bones
Appendicular skeleton: 126 bones

Connective tissues containing specialised cells and mineralised matrix of crystalline calcium phosphate and calcium carbonate. Consists of an organic(collagen -elastic) and inorganic(mineral crystal Hydroxyapatite - contribute to rigidity) component. The proportion/ratio of these components vary, i.e between antlers(high collagen), auditory ossicles(high mineral) and long bones(iso). Without mineralisation, the bones will be very brittle, dry and easy

Osteoblast: immature bone cell which secretes organic components of matrix

Osteocyte: mature bone cell(from osteoblasts) that maintains bone matrix

Osteoprogenitor cell: stem cell whose division produce osteoblasts

Osteoclast: secretes acis and enzymes to dissolve bone matrix

Compact bone, spongy bone, bone marrow

A tissue that fills the internal cavity in bones, it is dominated by blood cell or adipose tissue.

Inner layer of the bone which is a composed of a network of body struts(trabeculae). there is many empty cavities therefore no need to have a canal system. The nutrients are passed through by diffusion. Thetrabeculae of spongey bone are aligned with the direction of stress. Theychange shape to give resistance to stress and strains on the bone

Dense connective tissues composed of chondrocytes with a more gelatinous, less calcified matrix(glycoprotein material-chondroitin) than bones and has an abundance of matrix. It is an avascular tissue that provides support and allowsfor some flexibility of movement.

Perichondrium, chondrocytes, lucunae

Hyaline, Elastic, Fibrocartilage

Intramembranous 'ossification in membrane', endochondral 'ossification in cartilage'

no cartilage precursor, but rather directly from connective tissue where osteoblasts lay down bone in fibrous tissue from mesenchymal cells.

The rate of osteoclasts destroying bone and osteoblast forming bone tissue are roughly equal.
More physically active: rate of formation > degredation

old age: formation < degredation. Bones become weaker.

Synarthrosis(no movement): bony edges interlock like a jigsaw e.g skull

Amphiarthrosis (little movement): stronger than a freely moveable joint. connected by collagen fibers or cartilage.

Diarthrosis(free movement): a form of joint articulation/synovial joint that permits movement.

Cartilaginous: held by a thin layer of hyaline and/or fibro-cartilage e.g epiphyseal plate Between vertebrae

Fibrous: are those joints where the articular surface of the bones are attached to each other through fibrous connective tissues. e.g joined bones of the skull e.g attachment of the fibula nd tibia to the ligament

Synovial joints:(most common)are freely movable joints covered with a layer of articular cartilage within a joint capsule that contains synovial fluid. The fluid is lined with synovial membrane and reinforced by a fibrous capsule and ligaments

Large in diameter, low number of capillaries, fast contraction, rapid fatigue.

Smaller in diameter than fast fibers, take three times as long to contract. are fatigue resitance, contain a large amount of myoglobin, have a more extensive network of capillaries.

Have properties between fast and slow muscle fibers.

The flatter end of mesoderm at which limb development occurs

Mesenchyme causes condensations when losing influence from the AER and produces Cartilage Templates(CT's) which ossify and become bone. Cartilages are laid down in a proximo-distal sequence/patterning. This is done by HOX genes

Regulated by the zone of polarising activity (ZPA) which initiates sonic hedgehog expression(shh). Shh expression dictates digit location. Whe a shh bead is placed in another spot, it causes mirror image duplication.

Limb muscles originate in the somites and myoblasts migrate into the limb bud and arrange on opposite sides of the cartilage template. The limb muscle cells arrange into masses and cleave into individual muscle cells

Function is to protect spinal cord and spinalnerves, support body weight, posture and locomotion, flexibility.

Consists of 33 vertebrae arranged in 5 regions: cervical, thoracic, lumbar, sacral, coccygeal.

During foetal development the spine is C shaped (primary curve - thoracic and sacral). The lumbar and cervical S-shaped curvatures(secondary curves) develop during childhood in association with lifting the head and assuming upright setting. Curves are important because they increases column strength, help maintain balance, absorbs shock during walking.

Kyphosis - excessive posterior thoracic - hunchback

Lordosis- excessive anterior curvature - bum sticks out

Scoliosis - excessive lateral curvature

Centre of gravity moves from the thorax(gorilla) to the pelvis(human).

Vertebrae size increases across evolution because humans have to carry a larger load due to gravity.

C1- C7. start at the top of the skull. C1(atlas), C2(axis). Bodyis small and wide laterally, to distribute the weight of the head across alarger surface-provides more support. Vertebral foramen is prominent, largeand triangular because spinal cord is larger at the top. Transverse foramina - passage forblood vessels

L1-L12. Extends to accommodate for pregnancy.

Outercollar made of ligaments and fibrocartilage. Its function is to bind vertebraetogether, resist tension on the spine, and absorb compressive forces.

Gelatinous inner sphere of the intervertebral disc. Enables spine to absorb compressive stresses

The costal cartilage start to fuse together before it attaches to the sternum.

True Ribs 1-7: Connected to the sternum s.cn

False Ribs 8-12: Do not attach directly to the sternum. Ribs 11-18: floating ribs and are only attached to back muscle

The evolutionary development and diversification of a species or group of organisms, or of a particular feature of an organism.

The development of an individual organism or anatomical or behavioural feature from the earliest stage to maturity.

CT scans use emission of rotating X rays with multiple detectors. MRI measures hydrogen atom emission of a radio frequency in a strong magnetic field and constructs imagery from the detected frequencies picked up by a coil around the object.

elastic tube of stratified squamous epithelium located between the urinary bladder(anterior) and rectum(posterior).open sinto the vestibule and leads up through the cervix and into the uterus.