Compendium 2. The Cells and Tissues Flashcards
Describe the Plasma Membrane (hint : 4 functions)
- Supports and encloses the cell
- Attaches cells to other cells and to the surrounding matrix
- Communicates to the cell’s environment and other cells
- Determines what moves into and out of the cell (selectively permeable)
- Lipid bilayer
Describe the Cytoplasm
- Contains the organelles and cytosol
Describe the Cytosol
- The liquid component of the cytoplasm
Describe the Cytoskeleton
- The structural support of the organelles within a cell
- Made up of microtubules and microfilaments
- Responsible for the cell’s shape
Describe the Nucleus
- The control centre of the cell
- Deoxyribonucleic acid (genetic material) is held within the nucleus
- Contains nucleoplasm
Describe the Nucleolus
- Produces ribosomes
Describe what Ribosomes are
- The sites at which protein synthesis can occur
Describe the Endoplasmic Reticulum and the two types
- Usually surrounds the nucleus
- Rough ER assists in the synthesis of proteins
- Also has ribosomes attached, making it rough
- Smooth ER assists in the synthesis of lipids, steroids and carbs
- Also assists in the detoxification of harmful substances
Describe the Golgi Apparatus
- Packages and distributes proteins and lipids made by the endoplasmic reticulum
Describe what Lysosomes are
- Break down and digest unused/unwanted molecules no longer needed within the cell
- Contain digestive enzymes
Describe the Mitochondria
- Provides energy used to power the cells functions
- The site of ATP production
- Contains it’s own genetic material
Describe the Centrioles
- Involved in cell division (mitosis)
- Two centrioles positioned in a 90 degree angle are called a centrosome
Describe what Cilia is
- Long, hair like extensions from the cell membrane that help molecules move across the surface of the cell
Describe what Flagella is
- Longer than cilia and are only found on sperm cells (one flagellum per sperm)
- Helps the sperm swim/move around
Describe what Microvilli is
- Extensions of the plasma membrane that are much smaller than cilia
- Increases surface area
What is the study of Histology?
- The study of tissues
- Looking at the tissues in more detail by staining them
What are the four stages of preparing tissue?
- Remove the tissue from the body
- Fixation of tissue
- Embedding of tissue
- Slicing of tissue and mounting on a slide
What is the difference between biopsy and autopsy?
- Biopsy is when tissue is extracted from an alive person
- Autopsy is when tissue is extracted from a deceased person
Describe what is involved in fixating a tissue
- A process of placing a tissue in a mixture of chemicals (fixatives) to stop of reactions from occurring - Basically preserves the cells
Describe what is involved in embedding a tissue
- Tissue is infiltrated with a wax and is allowed to set so it becomes hard and is able to be cut
Describe what is involved in slicing a tissue
- The tissue is cut using a microtome (a mini meat slicer)
- The tissue is then placed on a slide where the wax must be dissolved and the tissue itself needs to be stained
What is Haematoxylin & Eosin (H and E)?
- A stain used on tissues that need to be viewed underneath a microscope.
- Haemotoxylin stains the nuclei of the cell purple
- The Eosin staines the other parts of the cell, aka the cytoplasm, pink
What are two things you need to consider when examining historical images?
- The plane in which the tissue has been cut
2. The magnification of the tissue
What are the four primary tissues?
- Epithelial - covers
- Connective - support
- Muscle - movement
- Nervous - control
What does Avascular mean?
There is no direct supply of blood vessels (vascular meaning there is a supply of blood vessels)
What does Innervated mean?
There is a direct supply of nerves
What is the Epithelial tissue’s role within the body?
- Covers and protects surfaces inside and out of the body
- It forms boundaries between different parts of the body
What is the Connective tissue’s role within the body? (hint ; 5 main roles)
- Binds
- Supports and protects
- Insulation
- Acts as a fuel reserve
- Transport
Describe simple, stratified and pseudostratified
Simple - A single layer of cells
Stratified - Multiple layers of cells
Pseudostratified - Looks like multiple layers of cells but is in fact only one layer
Describe squamous, cuboidal, columnar and transitional
Squamous - flat
Cuboidal - cube shaped
Columnar - column shaped
Transitional - can transition from a columnar to a cuboidal or squamous shape
What cells are commonly found in connective ?
- Adipose
- Fibroblasts
- Mast cells
- Leucocytes
- Macrophages
What are the 3 types of fibres make up connective tissue?
- Collagen fibres
- Elastic fibres
- Reticular fibres
What is ground substance?
It fills the spaces between the cells and suspended fibres.
What are the 4 classes of connective tissue?
- Connective tissue proper
- Cartilage
- Bone
- Blood
What are the different divisions of connective tissue proper?
Dense
- Regular
- Irregular
- Elastic
Loose
- Areolar
- Adipose
- Reticular
What are the characteristics and functions of cartilage?
Characteristics :
- Made up of cartilage cells (condracytes) that have a rigid matrix
- Avascular and not innervated
Functions :
- Protection
- flexibility
- ability to withstand pressure
What are the 3 types of cartilage and where are they found?
- Hyaline Cartilage
Found in rib cage and trachea - Fibrocartilage (Found in areas that withstand large amounts of pressure)
Found in the intervertebral discs and pubic symphysis - Elastic cartilage (Found in areas that must maintain shape while allowing elasticity)
Found in the ear and epiglottis
What are the characteristics and function of bone?
Characteristics :
- Composed of cells (osteocytes) and matrix
Function :
- Supports
- Protects
What are the 2 types of bone?
- Spongy bone
- Found at the ends of long bone, the sternum, vertebrae and pelvis - Compact bone
- Found in the shaft of long bone and makes up the outer portion of bones
What are the characteristics and functions of blood?
Characteristics :
- Considered atypical because it doe not ‘support’ or ‘connect’ anything
- Considered a connective tissue because it comes from the same precursive tissues as other connective tissues.
- Made up of erythrocytes, leucocytes and platelets
Function :
- Transport of nutrients, oxygen and wastes around the body
What is the main function of muscle?
It is responsible for the body’s movement through contraction
What are the 3 types of muscle?
- Skeletal
- Cardiac
- Smooth
Explain the characteristics of skeletal muscle
- Muscles that are attached to the bones
- Each cell has more than one nuclei
- Striated due to microfilaments
- Mostly under voluntary control (except for twitching)
Explain the characteristics of cardiac muscle
- Only found in the walls of the heart
- Responsible for pumping blood
- Cells have multiple mitochondria
- Under involuntary control
Explain the characteristics of smooth muscle
- Mainly found in the walls of ‘hollow’ organs eg stomach, bladder, uterus
- Non-striated
- Only have one nucleus per cell
- Involuntary control
- Elastic
What is the nervous system responsible for?
Control and communication within the body
What is nervous tissue made up of ?
- Neurons (which conduct electrical and chemical signals throughout the body)
- neuroglia (support cells that insulate and protect the neurons)
The brain, spinal cord and nerves are all parts of the nervous system
Where can simple squamous epithelium be found?
- Alveoli of lungs
- Kidneys
- Pericardium
- Peritoneum
Where can simple cuboidal epithelium be found?
- Kidney tubules
- Terminal bronchiole
Where can simple columnar epithelium be found?
- Intestines
- Stomach
- Fallopian tubes
- Lungs
Where can transitional epithelium be found?
- Bladder
- Ureters
- Upper part of the urethra
Where can stratified squamous epithelium be found?
Keratinised :
- Soles of the feet
- Palms of hands
- Skin
Non-keratinised :
- Mouth
- Oesophagus
- Anus
- Vagina
Where can stratified cuboidal epithelium be found?
- Sweat glands
- Salivary glands
- Developing ovum
Where can stratified columnar epithelium be found?
- Ducts of mammary glands
- larynx
Where can pseudo-stratified columnar epithelium be found?
- Pharynx
- Trachea
- Sperm
