Cells And Tissues Flashcards
Where are ribosomes formed
Nucleolus
What is the cell membrane ?
What is its function?
Phospholipid bilayer with proteins
Retains chemicals in cell and creates cell boundary
Communication
Monitors substances in and out the cell
Which type of cell has larger ribosomes ?
Eukaryotic
What are the functions of the rough endoplasmic reticulum ?
Protein production :
Lysosomal enzymes
Secreted proteins
Integral membrane proteins
What are the functions of the smooth endoplasmic reticulum ?
Lipid production In liver - glycogen to glucose In adrenal medulla - steroid hormone production In muscle - calcium storage Detoxifying into water soluable products
Functions of the Golgi apparatus
Protein modification
Storage of proteins
Packaging of proteins
What are vacuoles
Single membrane storage areas
Made via the fusion of many vesicles
What are vesicles
Much smaller deal with transport of molecules in and out of the cell
What are lysosomes and what do they do ?
Large vesicles
Contain hydrologic enzymes
Extra cellular breakdown of materials - phagocytosis
What makes up the cytoskeleton ?
What is the function ?
Microtubules, intermediate filaments, micro filaments
Maintain cells shape, cell movement, organelle movement, movement of chromosomes
What are the phases of the cell cycle (in order) and what occurs in them ?
G0: terminally differentiated cells G1: cells differentiate and perform functions S: nuclear Dna replication G2: cells prepare for mitotic devision M: mitosis occurs
What are the stages of mitosis and what occurs ?
Prophase - chromosomes visible, shorten, no nucleolus
Metaphase - chromosomes align in centre
Anaphase - chromatids to opposite poles
Telophase - chromatid - chromosome, envelope forms
Cytokinesis - cytoplasmic division
What are the 4 types of tissues ?
Nervous
Epithelial
Muscle
Connective
What can cause changes to tissues ?
Stress - physical and chemical Infection Poor diet Genetic / congenital Degenerative , neoplasms
What is the limit of resolution for the eye ?
What is the limit for a microscope ?
Eye - 0.2mm
Microscope - 0.2 micrometers
What are the stages in tissue preparation ?
Fixation Dehydration Embedding Sectioning Staining
What are the characteristics of epithelial ?
Highly cellular
Very little extra cellular matrix
Cells bind via adhesions/ junctions
Avascular - avoids blood loss !
What is epithelial tissue at risk of ?
At risk of abnormal growth and tumours when regenerating as most common in areas of wear and tear
What are the sides of epithelial cells called ?
Free apical surface
Lateral surfaces
Basal surface
What are microvilli ?
What are the functions ?
Cytoplasmic protrusions
Increases surface area for absorption
What are cillia ?
Where are they found ?
Motile hair like projections
Beat in coordinated movements to move substances
Found in respiratory epithelium
What are stereocilla ?
Where are they found ?
Non motile longer projections
Limited
Only In sensory hair cells of inner ear - epididymis / vas deferens
Increase surface area for absorption
Disease associated with epithelial ? Specifically oral mucosa
Apthalous ulceration
Common in 20% of population
Caused by local trauma or deficiencies in iron/ vit b12
What type of epithelium if found in lining blood vessels, heart , alveoli
Simple squamous
What type of epithelium is found in glands, some ducts, bronchioles and stomach ?
Simple columnar
What type of epithelium is found in the skin ? And the mouth larynx oesophagus ?
Skin - keratinised stratified squamous
Rest - non keratinised stratified squamous
What epithelium is found in salivary gland ducts, sweat glands and ovarian follicle cells (rare)
Stratified cuboidal
What are the functions of simple squamous ?
Diffusion , filtration absorption
Little barrier against friction
What is the function of simple columnar ?
Some have cillia so movement of substances, absorption, secretion
Offers more protection
What is the function of stratified squamous ?
Protection against friction , barrier to infection, reduction of water loss
What is the function of stratified cuboidal ?
Secretion , absorption, protection against infection
What is the function of psuedostratified columnar ?
Almost always ciliated
Synthesise and secrete mucous, movement of mucous
What epithelium is found in the lining of nasal cavity, pharynx, bronchi, trachea ?
Psuedostratified ciliated columnar
What special type of epithelium lines the bladder?
Why is is special ?
Transitional epithelium
Changes to accommodate great stretch and recoil with no damage to cells
What are the three main classes of connective tissue ?
Proper - loose/ dense
Supporting - bone/ cartilage
Fluid - blood / haemopoietic
What are the functions of connective tissue ?
Connections Support Protection
Separation
Cushioning / insulation
Transportation ( blood )
Common characteristics of connective tissue ?
Common germ layer - embryonic mesenchyme
2 components - specialised cells + ecm
What is extra cellular matrix made up of ?
Protein fibres
Ground substance
Blasts ?
Cytes?
Clasts ?
Create
Maintain
Breakdown
What is ground substance ? And what is it like ?
Fluid and gel like
Cell adhesion proteins act as glue
Proteoglycans acts and core to which gags attach
Allows movement
What are examples of cell adhesion proteins ?
Fibronectin
Osteonectin
Chondronectin
What are some important glycosaminoglycans ?
Hyaluronic acid Chonorotin sulphate Keperan sulphate Dematon sulphate Keraton sulphate
Which is the most abundant connective fibre ?
Collagen
What type of collagen is cartilage ?
Type 2
What type of collagen are reticular fibres ?
Type 3
What classification are areolar, reticular, adipose ?
Loose proper - not so many fibres
What fibres fall into the proper dense classification ?
Regular / irregular elastic
Regular/ irregular collagen
Greater number of fibres
Where is areolar tissue found ?
Skin / underlying muscle
Where are reticular fibres found
Lymph nodes, liver
What type of elastic is found in the dermis of skin ?
Irregular collagenous
What is scurvy ?
What is is caused by ?
What are the effects ?
Defective collagen fibres - unstable
Due to vitamin c deficiency ( ascorbic acid )
Bleeding from capillaries
Bleeding gums, loosened teeth
What is marfans syndrome
What causes it ?
What are features of the disease ?
Defective elastic fibres due to abnormal production of fibrillin 1
Over growth of tissues - very tall, greater arm span
Dilated aorta, valve prolapse
High arched palate, crowding, rotation of upper incisors
What are the 3 types of cartilage ?
Hyaline , elastic , fibro
What are the characteristics of hyaline cartilage ?
Where is is found ?
Most abundant
Articular joints, costal (ribs) nasal pathway , embryonic skeleton, growth plate
What is different about fibro cartilage ?
Where is is found ?
Lacks perichondrium
Invertebral disks, symphysis pubis, articular disks of tmj, menisci of knee joint
What are the percentage components of bone ?
Organic - 35% protein fibres and proteoglycans
Inorganic - 65% calcium and phosphate
What is concentric lamellae ?
Surrounds the osteon
What is an osteon ?
Central Canal and vessels surrounded by concentric lamellae and osteocytes in lacunae
Havesian system
What is a volkman canal ?
Where blood vessels enter via canals perpendicular to the long axis
What is outer lamellae called ?
Circumferential
What is lamellae inbetween osteons called ?
Interstitial
What are the 3 layers of the skin ?
Epidermis
Dermis
Subcutaneous
What are the 5 layers of the epidermis ?
S. Corneum S. Lucidium S.granulosum S. Spinosum S. Basale
What cells make up the s. Corneum
Dead keratinocytes, these shed off - protection
Which layer is only present in thick skin ?
S. Lucidium
What cells are in the s. Spinosum
Living keratinocytes, denitrific cells , melanocytes
What are merkel cells ?
Sensory receptors
What are langerhans cells
Antigen presenting immune cells
What are the two layers of the dermis and what do they contain?
Papillary - projects into epidermis contains nerve endings and blood vessels
Reticular - dense and fibrous
What are the layers of mucous membranes ?
Where are they found ?
Epithelium, lamina propria ( supportive areolar)
Any surface continuous with external environment
Lubricated with mucin
Which type of papilla don’t have taste buds ?
Filiform papilla
What are the features of cardiac muscle ?
Branched One centrally located nuclei Intercalated disks Striated Large diameter, small length
What are the features of smooth muscle ?
Fusiform, Central nuclei
Non striated
Small diameter
Medium length
What are the features of skeletal muscle ?
Long cylindrical Many peripheral nuclei Striated Very large diameter Very large length
What is the outer layer of muscle called ?
Epimysium
What layer is wrapped around each muscle fascicle
Perimysium
What tissue is around each muscle fibre ?
Endomysium
Short range hormone activity ?
Long range hormone activity ?
Paracrine
Neurocrine
What patterns of secretion are there ?
Chronic - over days and weeks
Acute - over minutes/ hours
Episodic - over days
What types of regulation are there in the body ?
Humoural - blood Bourne molecules
Neural - neurone stimulated hormone production
Hormonal - one stimulated another
What type of exocrine glands are found in the stomach ?
Simple tubular branched
What type of glands are mucous glands ?
Compound tubular
What is a merocrine gland ?
Vesicles release contents, ducts release outwards
What is a apocrine gland ?
Part of cell released with contents - cell debris
What is a holocrine gland ?
Dying cells release secretory product - cell debris
What is extra cellular fluid made of ?
Interstitial fluid - 11 litres
Plasma - 3 litres
How many litres of Inter cellular fluid is there ?
28
