Introduction to Cell Biology Flashcards
Define Endocytosis
Movement of particles into cell
Define Exocytosis
Movement of particles out of cells
What is a cell?
Small units bound by membrane/cell wall.
Smallest living entity, i.e. fundamental unit of life
What is Cytosol
Aqueous fluid within cells
What is Cytoplasm?
Chemicals within the cells.
The substance between the cell membrane and nucleus, containing cytosol, organelles and other various particles
What is the function of cytoskeleton?
Provides structural support for the cell
What are organelles?
Membrane-bound structures, involved in cellular function
Spectrum of Life - from smallest to largest
- Atom
- Molecule
- Organelle
- Cells
- Tissues
- Organs
- Organ systems
- Organism
What are prions?
Proteins that are the smallest infectious agents. Also smallest thing of biological relevance
Example: bovine spongiform encephalopathy (BSE) proteins –> Mad Cow’s disease.
Properties of Living Things
- Harness energy
- Respire = O2 in, CO2 out
- Grow and Develop
- Biogenesis (reproduce)
Respond to stimuli
How do cells harness energy>
- Phagocytosis = uptake of particles; ‘cell eating’
- Pinocytosis = uptake of fluids; ‘cell drinking’
What is respiration?
The breakdown of C-based ‘fuels’ such as carbohydrates, fats or proteins, yields CO2
Requires O2 to drive the catabolism
What is differentiation?
Specialisation of cells as one grows and develop
What is cell proliferation?
- Division of somatic cells (body cells, non germ cells) = mitosis
- Division of germ cells i.e. sperm and oocytes = meiosis
What is hypertrophy?
cells increase in size. DO NOT DIVIDE
Example: With exercise, muscle cells increase in size
Can be associated with disease: cardiomyopathy and cirrhosis of the liver
What is hyperplasia?
Abnormal increase in size of organ due to increased cell division in response to stimuli
NOT CANCER but can lead to it
??? Differs from cancer as with cancer cells it is the division of abnormal cells in a non-physiological manner that doesnt respond to stimuli
How do cells respond to stimuli?
- cells may move toward to stimuli cytochemotaxis
- divide in response to mitogens
- cell death
- undergo internal changes such as produce more proteins etc
Who was Robert Hooke?
-Coined the term ‘‘cell’’ via observing cork
- 1665 produced Micrographia: description and definitions of minute
- Considered the pioneer of Cell Biology
- Thought only existed in plants and fungi
Who was Aton van Leeuwenhoek?
- 1673 Advanced the development into microscopy. Considered a pioneer in microscopy
- Observed blood cells in vertebrates thus moving away from the notion that cells only exist in plants and fungi
- Discovered multiple structures such as bacteria, vacuole, spermatozoa etc
Who was Matthias Schleiden?
1838 - Concluded all parts of plant cells are made up of cells
Who was Theoder Schwann?
1839- Stated that all animal tissues are made up of cells
Who was Rudolf Virchow?
1858 -Concluded that all cells arise from pre -existing cells
What is the 19th Cell Theory?
- All organisms consist of one or more cells (Schleiden and Schwann)
- The cell is the basic structural unit of all organisms (Schleiden and Schwann)
- All cells arise from preexisting cells (Virchrow)
- ->’‘omnis cellula e cellula’’ all cells come from a cell - Virchrow
Cell theory postulates not only holds the cell be the fundamental unit of life but also to be the basis of reproduction
Who are Watson and Crick?
- Pricks who plagiarise and don’t reference
- ‘‘Discovered’’ the structure of DNA, the hereditary information that is passed from cell to cell
What does Modern cell biology consist of?
- Cytology
- Biochemistry
- Genetics
Key to understand cell biology to understand the basis of disease
Microscopy
Light microscope: brightfield, phase contrast, differential phase contrast, confocal, fluorescence
Electron Microscope: scanning EM and transmission EM
How do cells differ?
- Size
- Shape/structure
- Function
Erythrocyte
concave small and flat. Transports oxygen
Fibroblast
Spindle elongated cells. secrete extracellular matrix
Spermatozoa
Head with flagellum. Fertilize egg
Macrophage
Immune system, phagocytosis foreign bodies and dead cells
Neuron
Cell body with large protections. Neurotransmission of electrical signals
Keratinocyte
Pavement type tissues . Surface barrier, skin cells
Chondrocyte
produces cartialage
