Compendium 2 - Questions Flashcards
What is a cell?
The basic structural and functional unit in living organisms
What is a tissue?
- group of similar cells and the extracellular materials surrounding them.
- four primary tissue types found in the human body.
- Organs are made up of the four primary tissues.
Name the 4 primary tissue types found in the human body
1- Epithelial
2- Connective
3- Muscle
4- Nervous
Give a description of epithelial tissue
- contains lots of cells with little extracellular matrix
- free surface and basal surface sitting on basement membrane
- avascular; no blood vessels
- found lining entire body, tubes, hollow organs
What is histology study of?
- microscopic study of tissues to understand structure and function
- using a microscope
- tissue sampples fixed usual paraformaldehyde embedded in paraffin wax
What does haematoxylin and eosin stain?
Commonly used in histology stain
Haematoxylin stains nucleus purple
Eosin stains cytoplasmic cell pink
Explain the differences between; intracellular, extracellular, intravascular and intercellular
1- intra: inside cell
2- extra: outside cell
3- Intravascular: inside blood vessels
4- Intercellular - in between cells
What are the main components of a cell’s intracellular environment
- enzymes, water, ions, hormones, dissolved gases, proteins, cytoskeleton
Nucleus
Control centre of the cell
contains genetic material; DNA and chromatin: codes for proteins
Nucleolus
Produces ribosomes
Mitochondria
Energy powerhouse
ATP production
Ribosome
Protein synthesis
Lysosome
Digestive enzymes break down cell organelles
remove intracellular wastes; nucleic acids, lipids and proteins
Rough ER
Protein synthesis and modification via ribosomes
Smooth ER
Site of steroid, carbohydrate and lipid synthesis
detox harmful substances
Centrosome
Made up of 2 centrioles
Involved in growth of miotic spindle during mitosis
Golgi Apparatus
Modifies, packages and distributes proteins + lipids for secretion out of cell or use within the cell
Plasma membrane
Encloses and supports cellular contents
Controls what goes into and out of the cell
cell-cell communication
What types of cells would have large numbers of mitochondria and why?
- Kidney, liver and muscle cells
- have higher energy requirements and use energy at a higher rate
Name two types of cells that are multi-nucleated i.e. have more than one nuclei per cell? Why would cells be multi-nucleated?
Skeletal muscle cells and osteoclasts (cells which break down bone). These cells require more regulation
e.g. muscle cells require the constant synthesis of enzymes and proteins for their function
What types of cells would have a large amount of smooth endoplasmic reticulum and why?
1- Liver cells because they detoxify harmful substances. 2- Cells of the ovaries and testes because they produce the lipid-containing hormones estrogen and testosterone.
3- Adrenal glands in producing cortisol.
What type of cell might be expected to contain a well-developed and extensive Golgi apparatus?
Name two examples
Secretory cells in general e.g. goblet cells (mucus), pancreatic beta cells (insulin) or acinar cells (enzymes), stomach chief cells (digestive enzymes) and plasma cells (antibodies).
What is the difference between cytoskeleton, cytosol and cytoplasm
1- Consists of structural protein filaments that give shape to a cell, provide strength, stabilise the position of organelles and assist in cell movement.
2- Intracellular fluid, containing a mixture of water, salts, dissolved ions and organic molecules
3- The cell components outside the nucleus but inside the plasma membrane. All the intracellular fluid plus all the organelles except the nucleus.
Describe muscular tissue + example
- Contracts with a force to cause movement.
- Three kinds of muscle tissue; skeletal, cardiac and smooth.
- Skeletal muscles contract to move the body,
- cardiac muscles contracts to pump blood around the body,
- smooth muscles contract to decrease the size of organs such as the bladder during urination.
Describe connective tissue
- Very diverse in structure and function.
- Few cells and an abundance of extracellular material.
- Tendons and ligaments connect tissue together.
- Bone and cartilage support the body.
- Connective tissue capsule cover and protect organs (e.g. liver and kidneys).
Describe nervous tissue
specialised for information processing and conduction of signals quickly throughout the body.
Consists of neurons and supporting neuroglial cells.
Describe epithelial tissue
Covers and protects surfaces, both inside and outside of the body.
Comprised mostly of cells, sits on a basement membrane, nonvascular.
E.g. epidermis of the skin, linings of the digestive and respiratory tract, linings of blood vessels.
What is the function of the basement membrane that lies directly under the epithelial cell layer?
- Support, anchoring layer for epithelial cells
- Forms part of epithelial barrier
What type of epithelial tissue is found in the thyroid and what is its function. Provide other examples of where this type would be found
- Simple cuboidal
- Secretion and absorption
- glands, ducts, part of nephron, terminal bronchioles
What type of epithelial tissue is found in the trachea and what is its function. Provide other examples of where this type would be found
- Pseudostratified ciliated columnar
- Protection and secretion of mucous
- Nasal cavity, sinuses, bronchi, trachea
What type of epithelial tissue is found in the large intestines and what is its function. Provide other examples of where this type would be found
- Simple columnar
- Protection, secretion, absorption
- Lines stomach intestines, gallbladder, uterine tunes, collecting ducts in kidneys
What type of epithelial tissue is found in the skinand what is its function. Provide other examples of where this type would be found
- Keratinised stratified squamous
- Physical protection against abrasion, pathogens, chemical attack
- Reduce water loss
- Skin only
What type of epithelial tissue is found in the capillary and what is its function. Provide other examples of where this type would be found
Simple squamous
- Quick diffusion, filtration, some secretion and friction
- Alveoli, blood vessels, thin part of loop of henle, inner lining of heart and body cavities
What type of epithelial tissue is found in the bladder and what is its function. Provide other examples of where this type would be found
- Transitions
- Permits expansion and recoils when relaxed
- Bladder, ureter, renal pelvis
What type of epithelial tissue is found in the oesophagus and what is its function. Provide other examples of where this type would be found
- non keratinised stratified squamous
- physical protection against abrasion, pathogens and chemical attack in a moist infection
- lines oral cavity, pharynx, vagina, rectum, anus
Cilia are appendages projecting from the cell surface
What is their function? Where in the body are they found?
Cilia beat in an organised motion and move material across cell surface.
important in areas such as the trachea where they whip up mucous with trapped particles to prevent them entering lower respiratory system.
