FBS revision

Where does fertilisation occur?

Ampulla of the fallopian tube

what does the trophoblast become?

Cytotrophoblast + synctiotrophoblast

Placenta

What does the outer cell mass and inner cell mass differentiate into?

Trophoblast

Embryoblast

What are the three germ layers?

Ectoderm

Mesoderm

Endoderm

What does the ectoderm give rise to?

Epidermis and nervous system

What does the mesoderm give rise to?

Dermis, muscles, skeleton, circulatory system

What does the endoderm give rise to?

Digestive tract

When is an embryo most at risk?

3-8 weeks

What does the sclerotome give rise to?

Tendon, Cartlidge, bone

What does the myotome give rise to?

Muscles

What is a teratogen?

An agent or factor that causes malformation of an embryo leading to congenital abnormalities

a. Acrosome

b. Nucleus

c. Centriole

d. Mitochondria

e. Flagellum

a. Corona radiata (follicle cells)

b. Cytoplasm

c. Zona pellucida (jelly coat)

d. Nucleus

a. Inner cell mass/ embryoblast

b. Blastocoele

c. Outer cell mass/ trophoblast

a. Branchial arches

b. Somite

c. Arm bud

What are the 2 germ cell layers before the 3 are formed?

Epiblast

Hypoblast

What cells line the oesophagus?

stratified squamous epithelium

What type of cells line the small intestine?

simple columnar epithelium

What type of cells line the respiratory system?

Cuboidal ciliated

What type of cells line the bladder?

Transitional epithelium

What type of fluid is normally found in the pleural space, and what is its function?

Serous fluid

Lubrication

What is the difference between desmosome and hemidesmosome?

A desmosome connects two cells together while a hemidesmosome connects a cell to the basal lamina

What are the different types of cell junctions?

tight junctions (occluding): seal cell together to prevent leakage

gap junctions (communicating) : allows passage of small molecules between cells

desmosomes (anchoring): connect cells together/ to the basement membrane

Difference between exocrine and endocrine glands

Exocrine: secrete onto surface via ducts

Endocrine: secrete directly into blood and controlled by hypothalamus and pituitary, ductless

What serous membrane covered the heart?

Pericardium

What is a serous membrane?

A thin, continuous membrane lining a closed cavity of the body and covering its organs

Parietal vs Visceral Membranes

PARIETAL - double-layered membrane attached to wall cavity (outer layer)

VISCERAL - double-layered membrane covering the internal organ (inner layer)

What do condition to cells used for microscopic slides need to be in?

Fixed

Sliced

Stained

What are the layers of the epidermis? (From the top)

stratum corneum

stratum lucidum (only in thick skin)

stratum granulosum

stratum spinosum

stratum basale

What are the 4 cells of the epidermis?

keratinocytes

melanocytes

langerhans cells

merkel cells

What does a Meissner's corpuscle detect?

light touch and vibration

** found in papillary dermis

What does the parcinian corpuscle detect?

Deep pressure/vibration

** found in reticular dermis

What does the Ruffini corpuscle detect?

stretch of skin

** found in reticular dermis

What are the layers of the skin starting from the top?

Epidermis

Dermis

Hypodermis (subcutaneous tissue)

1st degree burn (superficial)

Only epidermis

2nd degree burn (partial thickness)

Epidermis and dermis

3rd degree burn (full thickness)

Epidermis, dermis, hypodermis

What cells line the trachea ?

pseudostratified ciliated columnar epithelium

Where do you find thick skin?

Heels and palms

What is the function of the stratum granulosum?

Water barrier

What does connective tissue consist of?

cells(Fibroblast, adipocytes,macrophages, mast cells ) +

extracellular matrix (collagen, elastin)

What type of collagen are reticular fibres made up of?

Type III

What is the point at which the trachea bifurcates called?

Carina T4/5

What is the difference between regular and irregular dense connective tissue?

Regular dense CT - collagen fibers are arranged parallel to each other with fibroblasts and strength is in 1 direction

Irregular dense CT - collagen fibers are arranged randomly and strength is in multiple directions

Difference between loose and dense connective tissue?

Loose is widely spaced with collagen and elastin and dense is tightly packed by collagen fibres

Skeletal muscle

striated and voluntary

Location: muscle attached to bone

cardiac muscle

involuntary, striated

Location: heart

smooth muscle

involuntary, non-striated

Controls movement of hollow organs

Why does the trachea have c shaped cartilage?

Support and to allow it to move

Structure of tube in digestive tract (from the outside)

Adventitia

Smooth muscle

Submucosa

Mucosa

Lumen

What cells are found in the stomach?

Patietal (oxynitic) cells: produces HCl

Chief (Zymogenic) cells: produces enzymes

Endocrine cells: produces hormones

Where is the appendix located?

Outgrowth of the caecum

What cells make up cartilage?

Chondocytes

Skeletal muscle

Smooth muscle

Cardiac muscle

Hyaline cartilage

Fibrocartilage

Loose connective tissue

Dense regular connective tissue

Dense irregular connective tissue

What are the airway layers?

1. Respiratory epithelium: pseudostratified columnar, ciliated + BM. Also contain goblet cells which form mucus.

2. Lamina propria: contain connective tissue, blood and lymph - give nutrients and structural support.

3. Submucosa: seromucus glands, smooth muscle/elastin fibres.

4. Cartilage: hyaline cartilage - C-shaped in trachea, but less prominent as tubes get smaller.

What vessels make up the portal triad?

the hepatic artery, the hepatic portal vein and the bile duct

Describe the lovers dual blood supply

The hepatic artery delivers oxygenated blood from the general circulation.

the hepatic portal vein delivering deoxygenated blood from the small intestine containing nutrients

Which muscle that controls the diameter of the trachea

Trachealis muscle

What is part of the axial skeleton?

Vertebral body, ribs, sternum, skull

What is part of the appendicular skeleton?

pelvic girdle, pectoral girdle, bones of limbs

Where is compact bone usually found?

Exterior of bone, surrounding the spongy (cancellous) bone

What part of the bone contains bone marrow?

Medullary cavity

How are foetal bones transformed into adult bones?

Endochondral ossification

Hyaline cartilage → adult bone

What is a pneumatic bone?

Bone filled with air

Usually found in the face

What is intramembranous ossification?

ossification spreads through a sheet of mesenchyme tissue (ossification of bones in the membrane)

** only for flat bones

Name the type of cartilages

Hyaline

Fibrocartilage (yellow)

Elastic (white)

What is endochondral ossification

Cartilage is infiltrated by 3 blood vessels forming 3 ossification centres - 2 epiphysial (ends) and 1 diaphyseal

Where is the primary ossification centre in long bones?

Diaphysis

What do osteoblasts do?

Secrete collagen to build bone matrix

What do osteocytes do?

Maintain bone tissue

What do osteoclasts do?

Breakdown old/damaged bone

What is a compact bone made up of?

Bony lamella strongly packed together

Haversian systems (concrete rings surrounding a central canal that contains blood vessels, nerves, osteocytes)provide strength to the bone

What are the steps of fracture repair?

1. Inflammation(haematoma): Immune cells clean up debris

2. Soft callus formation: Fibrous tissue and collagen stabilise

3. Hard callus formation: Osteoblast produce new cells forming woven bone

4. Remodelling: Woven bone is turned to Lamella bone (stronger)

What are the different types of joints?

Fibrous: Fixed

Cartilaginous: Slightly movable

Synovial: Highly movable

At what level is the larynx?

C3-6

What does the larynx contain and do?

Vocal cords

Prevents food entering trachea

At what level is the trachea?

C6-T4/5

Where does the trachea bifurcate?

Carina T4-5

At what level is the sternal angle?

T4-5 (2nd rib)

At what level is the diaphragm?

T10

At what level is the oesophagus?

C6-T10/11

How many lobes does the right and left lung have?

R: 3

L:2

Why does the left lung only have 2 lobes?

To leave space for the heart

Process of inspiration

1. External intercostal muscle contracts

2. Diaphragm contracts (flattens)

3. Chest wall expands (lung volume increases)

4. Atmospheric pressure > lung pressure

What is found in the superior mediastinum?

oesophagus, trachea,thymus, aortic arch, brachiocephalic trunk, L common carotid artery, L subclavian artery

What is found in the middle mediastinum?

pericardium, heart, ascending aorta, pulmonary trunk, superior vena cava, phrenic nerves

What is found in the posterior mediastinum?

descending aorta, oespohagus, vagus nerve

How do the right and left bronchi differ from each other and why important?

R: shorter and wider

More likely for particles to get dislodged and entering R lung

a. Epiglottis

b. Hyoid bone

c. Thyroid cartilage

d. Laryngeal prominence (Adam’s apple)

e. Cricoid cartilage

a. Jugular notch

b. Sternoclavicular joint

c. Clavicle

d. Acromioclavicular joint

What is the name of the space between the lungs and diaphragm?

Costodiaphragmatic recess

** safest place to collect fluid

What are the margin of the lung?

6th rib midclavicular

8th rib midaxillary

10th rib midscapula