Lecture 1 - Cytology, Basic Genetics and Histology Flashcards
(60 cards)
Cytology
study of cells
Histology
Study of tissues
Anatomy
study of structures (of body)
Physiology
Study of processes (of the body)
Metabolism
Sum of all chemical processes in body
Characteristics of death
- Loss of heartbeat
- Absence of breathing
- Loss of brain function
- No vital force (qi)
Homestasis
State of equilibrium, maintained by body’s own processes
Homestatic balance made up of:
- Core temperature (36.5 - 37.5 C)
- Water and electrolytes
- pH (acidity or alkalinity)
- Blood glucose levels (4-7 mmol/l)
- Blood and tissue O2/CO2 levels
- Blood pressure
- Flow of life force
Negative feedback
The output reverses the input
Positive feedback
Strengthens change in one of the body’s control system
Examples : childbirth, milk production
Body organisation (smallest to largest)
Atoms and molecules
Cells - smallest living units in the body
Tissues - group of cells working together to perform function
Organs - groups of tissues working together
Systems - related organs that have a common function
Organism - all body parts together
Vital Force - energy that creates life
4 body cavities
- Cranial
- Thoracic
- Abdominal
- Pelvic
What is the Cell Theory
- Cell - structural and functional unit of all living things
- All cells come from pre-existing cells - cell division
- Cells contain hereditary information
Oxidative stress
- Imbalance free radicals and antioxidants
- Free radicals - highly unstable and reactive, lack electron in atomic structure which can be donated by anti-oxidants
Prokaryotic cells
- No nucleus
- No membrane-bound organelles
- Cell wall
- Cell division - binary fission (rapid mitosis)
- Example - bacteria
Eukaryotic cell
- Membrane-bound nucleus
- Many membrane-bound organelles
- Cell wall - only present in plants/fungi
- Cell division - involves mitosis
- Examples - human/animal cells, plant/fungi
Cytosol
Basic watery fluid within the cell
Cytoplasm
Cell content excluding the nucleus (includes cytosol and organelles)
Phospholipid bilayer
- 2 layers - phosphate and lipid molecules
- Form the cell membrane
- Hydrophobic lipid ends - face inward - (tails on inside)
- Hydrophilic phosphate heads f- acing outward - (heads on outside)
3 functions transmembrane proteins
- Transport of substances in and out of cell
- Immunological identity
- Receptors (hormones)
Cell junctions - 2 types
- Tight junctions - stomach, intestines, bladder (prevent leakage)
- Gap junctions - small fluid-filled tunnels - nerves
Nucleus
- All body cells have nucleus EXCEPT RBCs (max oxygen carrying)
- Controls all cell functions
- Nucleolus produces RNA
What do Chromosomes contain
DNA
Genes
- Subsections of DNA that act as instructions to make proteins
- Located along chromosomes
- Thousands per chromosome
- All body cells (somatic cells) contain the full genome (full set of genes)
- One gene codes for the production of 1 protein
- Genes are switched on depending on each cell’s job