TEST 3 SAQs Flashcards
List the types of salivary glands and their functions.
Glands which produce saliva
Parotid, submandibular and sublingual
Location:
1. Parotid – behind ears
2. Submandibular – below mandible
3. Sublingual - below tongue
Duct opens:
1. Parotid – opposite 2nd upper molar
2. Submandibular – either side of frenulum
3. Sublingual - base of cavity
Saliva functions:
Digestion, immunity, mastication.
Briefly explain the movement and blood supply of the digestive system.
Movement:
- Peristalsis- push the food bolus front
- Segmentation- mix the food with the secretions
Blood supply of the digestive system:
- Celiac artery, Superior and Inferior mesenteric artery supplies
GI tract.
- 1st capillary at GI system for nutrient absorption and second
capillary system at liver
List the components of the pharynx and explain the stages of deglutition.
Parts of pharynx
- Common passageway for food and air
- Pharynx is divided into nasopharynx, oropharynx and laryngopharynx.
Phases of swallowing:
- Complex process that transports food from pharynx to stomach
Three phases - oral (voluntary), pharyngeal(involuntary) and oesophageal (involuntary)
Oral phase:
- Food chewed to become food bolus
- Tongue touch hard palate and retracts to push the food bolus into oropharynx
- Soft palate closes the nasopharynx
Pharyngeal phase:
- Food touches pharynx wall → triggers swallowing reflex →Epiglottis closes larynx
Esophageal phase:
- Food enters oesophagus.
- Food travels down the oesophagus by peristalsis and reaches stomach
- Swallowing process can be affected in elderly and children resulting in aspiration and choking
Describe the liver’s histology as well as its portal circulation.
Microscopic unit:
- Basic functional unit of liver – hexagonal lobules. Liver has 100,000 lobules
- 6 Corners –> Portal area –> has a branch of Hepatic portal vein (HPV) , Hepatic artery (HA) and bile/ hepatic duct
Blood circulation:
- Branch of HPV carries blood from GI system with absorbed nutrients
- Branch of HA carries blood from heart with Oxygen:
Mixed blood from HPV and HA together flows through the sinusoids (lined by hepatocytes) - Nutrients from GI system and oxygen in the mixed blood enters the hepatocytes
- And the blood flows towards central vein which joins with other central veins, hepatic veins
Branch of bile duct carries bile produced from hepatocytes
- Bile is produced from hepatocytes –> flows towards bile duct to reach bile duct branch in portal area
- Branches join with bile duct branches –> forms hepatic duct which exits out of the porta hepatis
List the functions of the liver and pancreas.
Liver
- Solid digestive organ
- Metabolic regulation (storage detoxification)
- Haematological regulation, bile production
Pancreas
- Solid digestive organ
- Produces hormones – insulin
- Produces digestive enzymes
List the parts and functions of the fallopian tube.
Infundibulum:
* funnel-shaped with fimbriae – recievs the ovum
Ampulla:
* Widest part - fertilization takes place here.
Isthmus:
* Narrowest part; most common site for ectopic pregnancy
Intramural:
* Inside the muscle of the uterus
Explain the phases of the menstrual cycle.
Before ovulation
1. Follicular phase (ovary)
FSH from pituitary stimulates follicles to grow; Growing follicle releases estrogen
2. Proliferative phase (uterus)
Oestrogen acts the endometrium proliferate (Increases in endometrial cells, glands and arteries)
Ovulation (ovary)
LH stimulates the follicle to release ovum
After ovulation
1. Luteal phase (ovary)
After the release of ovum–> graafian follicle becomes corpus luteum –> secreting progesterone
2. Secretory phase (uterus)
Progesterone acts on the endometrium and maintains the lining for implantation
Menstrual phase (uterus)
Corpus luteum –> corpus albicans –> no progesterone –> blood vessels shrink –> endometrial shedding
Describe maternal physiological changes that occur during pregnancy.
Heart
Enlarges, increased cardiac output
Lungs
Compressed, increased respiratory rate
Kidneys
Increases blood flow, increased urine
GI system
Nausea, constipation
Uterus
Enlarges, grows to xiphoid level
skin
Stria gravidarum, linea nigra
Breasts
Increase in size, lactation
Blood
Increased protein, physiologic anemia
Joints
Laxity, mobility of joints
Weight
Weight gain max to 12 kg
Briefly explain one function of the testes, epididymis, prostate, seminal vesicle, and vas deferens
Testes:
* production of sperms and testosterone
Epididymis:
* Maturation and storage of sperms.
Prostrate :
* Adds 30% secretion to semen – has plasmin and prostate specific antigen
Seminal vesicle:
* Adds 60% secretion to semen – has fructose and fibrinogen
vas deferens:
* Propels sperms by peristalsis
Define ectopic pregnancy, PPH (postpartum hemorrhage), ovulation, fertilization, and striae
gravidarum.
PPH:
* Loss of more than 500ml of blood within the first 24 hours following childbirth.
Ovulation:
* LH stimulates the graffian follicle to release ovum.
Fertilisation:
* Union of haploid male (Sperm) & female gametes (ovum) –> zygote (diploid)
* Fertilization occurs usually within 12 - 24 hours after ovulation in ampulla
Ectopic pregnancy:
* Implantation of blastocyst occurs outside the uterus
Striae gravidarum:
* stretching of collagen in abdomen & thighs
Describe endospores and nosocomial infections.
Endospores:
* When environment becomes unfavourable, bacteria become endospores .
* Highly durable, dehydrated cells with extra thick walls, remain dormant and to vegetative state if conditions are
favourable
* They can be killed ONLY by autoclave
* E.g., Clostridium tetani spores can be found in soil.
* So, when a person gets a injury and comes in contact with soil, these spores can enter the body. After entering they
can become active bacteria and produce toxins. These toxins can attack the nervous system resulting in severe
spasms.
Nosocomial infection:
* Infections acquired as a result of stay in hospital, nursing home and health-related facility
* Routes of Transmission - Direct contact , Indirect contact
* Common Nosocomial infections
* UTI (50%
* Surgical wound infection (25%)
* Lower resp tract infection
* Bacteremia
Briefly describe each step of the infection chain.
Process:
* process of infection where the microorganism is spread from the reservoir to the host
6 parts:
* Pathogen - Infectious agent which causes disease
* Reservoir- Source of pathogens
* Portal of exit - portals where the pathogen is released from the reservoir
* Methods of transmission - Refers to how a pathogen is moved from reservoir to host
* Portal of entry - portals through which the pathogen enters the host
* Infection in the new –host- - depends on virulence, adherence and pathogenicity
Give a brief explanation of TB, tetanus, and gonococci.
Gonococci
Neisseria gonococci
gram negative cocci
Infected individuals
Sexually transmitted
Causes Gonorrhoea - genital infections
* Male - urethritis, prostatitis
* Female – cervicitis, pelvic infection
Tetanus
Clostridium tetani
gram positive bacilli
Endospores in soil
Enters through skin.
Causes tetanus
* Exotoxin interferes with
neurotransmitters
* Uncontrollable muscle
spasms eg. lockjaw
Tuberculosis
Mycobacteria tuberculosis
Aerobic acid-fast bacilli
Infected individuals
Droplet transmitted
Causes Lung tuberculosis
Spreads to other organs
Describe latent infection and tapeworm briefly.
latent infection:
* Virus after entering the host causes initial infection, after the infection, virus remains in host. When the host’s immune
system is compromised, virus comes out and cause latent infection.
* E.g., chicken pox (initial infection) –> shingles (latent infection)
Tapeworm:
* Pathogen - Flattened segmented worms
* Reservoir- humans (intestine), pigs & cow (muscle)
* Portal of exit – faeces
* Methods of transmission – Faeco- oral roue
* Portal of entry – oral
* Infection in the new host when human eats the eggs infested food, egg hatches in intestine and forms adult worms
Briefly describe the layers of the epidermis .
Functions:
* Sensory reception
* Temperature maintenance
* Excretion (sweat) and secretion (milk)
* Protection,
* Synthesis and storage of nutrients (Vit D)
Layers of epidermis:
* Stratum corneum (most superficial layer)
* Stratum lucidum
* Stratum granulosum
* Stratum spinosum
* Stratum basale (lowest layer)
