Cell Biology 1.1 Flashcards
Cell Theory
- All living things are composed of cells
- The cell is the Basic unit of life
- Cells only come from preexisting cells
7 functions of life:
- Nutrition
- Metabolism
- Growth
- Response to Stimuli
- Excretion
- Homeostasis
- Reproduction
Nutrition (as a function of life)
The process by which living things take in materials from its environment for growth and repair
Metabolism (as a function of life)
Chemical reactions inside the cell, including cell respiration to release energy
Growth (as a function of life)
Cells increase in size over time. When they are large enough and acquire the materials required they may divide
Response (as a function of life)
The ability to react to changes in the environment. Receptors in the plasma membrane detect molecules in the environment and send signals to the internal machinery of the cell
Excretion (as a function of life)
The process by which living things remove waste products produced by the cell’s activities
Homeostasis (as a function of life)
Cells maintain a stable internal environment by carrying out a continuous series of chemical reactions
Reproduction (as a function of life)
Producing offspring either sexually or asexually
Why is the SA to V ratio of a cell important in the limitation of a cell size
If a cell grew infinitely large it would reach a point where this balance between SA and V become imbalanced, meaning it used substances more quickly than it could obtain them. At this point cellular activity decrease and/or ceases.
What arises from the interaction of component parts of a cell?
Emergent properties help living organisms better adapt to their environments and increase their chances of survival.
Emergent Properties
How can it be that all of an organism’s cells have the same genetic information, but the cells have a wide variety of shapes and functions?
All cells are coded, meaning each cell has genes that are expressed, or ‘turned on’ and ‘turned off’. This is because that certain types of cells only require certain genes to create the proteins relevant to that cell.
What are key properties of a stem cell?
-undifferentiated (not specialized)
-ability to self-renew
-ability to give rise to various types of cells
Two types of stem cells:
Adult and Embryonic
Adult Stem Cells
-Found in adult tissue (e.g. neural cells, cardiac muscle, bone marrow)
-Can self-renew many times (but limited)
-Multipotent (only give rise to become cells in the tissue they came from)
Embryonic Stem Cells
-Can self renew forever
-Come from the blastocyst stage of an embryo
-Pluripotent (can give rise to become almost anything in body)
Totipotent Cells
A potency of a stem cell that allows it to differentiate into absolutely everything include supporting structures of pregnancy
Multipotent Cells
A potency of a stem cell that allows it only to differentiate into the cells from their tissue of origin
Pluripotent Cells
A potency of a stem cell that allows it to differentiate into almost every cell, excluding supporting structures of pregnancy
What factors make striated muscle cells an exception to the cell theory?
-each cell is much larger than most animal cells
-each cell has many nuclei
What factors make Giant algae an exception to the cell theory?
-Does not have cross walls or septa, and so forms an uninterrupted tube-like structure
-Many nuclei spread along tube
Difference in nutrition between Paramecium and Chlamydomonas
Ingests small organisms and digests through vesicals VS contains chloroplast and thereby produces own nutrition
Difference in Metabolism between Paramecium and Chlamydomonas
Both contain enzymes in the cytoplasm which catalyse the metabolic reactions
Difference in Growth between Paramecium and Chlamydomonas
Nutrients from digestion are used for energy and materials needed for growth VS able to grow through the absorption of minerals and photosynthesis
Difference in Response between Paramecium and Chlamydomonas
Cilia helps the cell to move, cells moves toward or away from external stimuli VS has an eyespot that allows it to detect the brightest light and therefore it moves towards the light stimuli
Difference in Excretion between Paramecium and Chlamydomonas
Waste products in both cells are expelled outside through diffusion
Difference in Homeostasis between Paramecium and Chlamydomonas
Both have contractile vacuoles which fill with water and expels it through plasma membrane, maintaining water levels constant
Difference in Reproduction between Paramecium and Chlamydomonas
Both reproduce asexually and sexually
What is Stargardt’s Disease
A genetic disease that results from a recessive mutation of a gene that effects photo receptor cells in retina
How can Stargardt’s disease be treated by stem cells?
Stem cells developed into retina cells which are injected into the eye. These healthy retina cells then attach to retina and remain, increasing quality of vision
Procedure in treating Stargardt’s disease with Stem cells
- skin taken from patients arm and used to make stem cells (to avoid rejection)
- Cocktail of proteins and vitamins are used to coax stem cells into growing healthy retina cells.
- Healthy retina cells injected into back of patients eye, restoring sight
How is Stem cell therapy used to treat Leukemia?
- Leukemia starts by leukocytes growing and functioning abnormally and are unable to fight infection 2. Chemotherapy used to kill bad leukocytes and allow body to grow healthy ones
- If chemotherapy is unsuccessful, the bone marrow killed by chemotherapy is replaced with healthy stem cells
What are the ethical considerations associated with the therapeutic use of ESCs? (Embryonic Stem Cells)
-Technology used could also be used for reproductive cloning
-Creation of stem cell line requires destruction of a human embryo
-embryos are a human life, and thus have the same rights of an individual
-Saving or enhancing the quality of life of an individual doesn’t justify the destruction of the life of another
-ESC research has not produced viable long term treatment whereas adult stem cells have
Characteristics of Stem cells obtained from Cord blood stem cells
-easily obtained and stored
-compatible with tissues of adult that grows from the baby
-Only naturally develop into blood cells
-limited quantities of stem cells in one chord
-the umbilical chord is discarded whether stem cells are taken or not
Formula for Magnification:
Magnification = Image size / Actual size
Formula for Actual size
Actual size = Image size / Magnification
How many Nanometres in a Meter?
10 to power of 9
How many Micrometres in a Meter?
10 to power of 6
Atypical Cells
-Straighten muscle tissue composed of repeated units of sacomeres that show striped patterns
- Muscle cell is multi-nucleated
Aseptate Fungal Hypae
- Long threads with many nuclei
Viruses
- Non living entities, no property outside cell, no cellular structure-but the do have protein coats of DNA or RNA
Flagella
Movement of Chalmydomnas
Chalmydomnas
Unicellular green algae over the world in soil, water, oceans and mountains
Lissenphaly
Disorder where cortex doesn’t fold right and issues development problem for children dying at age of 10 with no development for 3-5 months.
Villi
Folds up SA when exposed to digestive food
Microville
Makes even more folds for space when exposed to digestive food
Celiac Disease
disorder where immune system destroys the villi - in small intestine which causes gluten issues
Emergent Properties
whole organism can do more things than individual cell can do because interaction with different parts
“are properties of a group of items, whether insects, atoms or buildings, that you would not find in any of the individual items. Examples of emergent properties include cities, the brain, ant colonies and complex chemical systems”.
Parkinson Diease
Parkinson’s disease is caused by a loss of nerve cells in the part of the brain called the substantia nigra. Nerve cells in this part of the brain are responsible for producing a chemical called dopamine.
Coarse focus dial
used to initially focus a light microscope on a specimen.
Differentiation
the alteration of a cell’s morphology and physiology through changes in gene expression.
Emergent property
a property of a system that emerges from the interaction of the elements of the system.
Objective lens
the part of the microscope that gathers light from the specimen and focuses it to produce a real image.
Paramecium
genus of single-celled ciliated organisms.
Stargardt’s disease
a degenerative eye disease that has been the target of stem cell research.
70S
the size of prokaryotic ribosomes.
80S
the size of eukaryotic ribosomes.
Archaea
a domain of prokaryotes.
