Unit 1 - Cells Flashcards
What are the postulates of cell theory? (3 points)
- all organisms are made up of one or more cells
- cells arise from pre-existing cells
- cell are the smallest units of life
What are the functions of life? (7 points)
- Metabolism
- Reproduction
- Sensitivity
- Homeostasis
- Excretion
- Nutrition
- Growth
What is the study of all aspects of a cell called? (1 pt)
Cytology
What happens when the SA:Vol ratio of the cell is low? (2 pts)
The metabolic rate of the cell will be higher than the rate of vital material and waste exchange, killing the cell.
Why do cells related to Gas/material exchange have a high SA:Vol ratio? (2 pts)
The large surface area optimises material transfer (e.g., Intestinal villi and microvilli of the alveoli)
How are specialized tissues and cell differentiation related? (2 pts)
cell differentiation allows for different cell types which, when interacting with each other, carry out unique functions (e.g., skin cells emerging into skin tissue)
What are the exceptions to cell theory?
3 pts + explanation
- Striated muscle – many nuclei along the length of a single cell/muscle fibre
- Giant algae – Large organisms containing only one nucleus
- Hyphal aseptate fungi – hyphae are not divided into cells and contain many nuclei in a single hypha
Stargardt’s disease:
Juvenile _____ degeneration (a mutation of the gene in which the ________ of the ______ in the retina are impaired, causing progressive loss of eyesight and eventual blindness.)
Stargardt’s disease:
Juvenile Macular degeneration (a mutation of the gene in which the energy transport of the photoreceptors in the retina are impaired, causing progressive loss of eyesight and eventual blindness.)
Parkinson’s disease:
Degeneration of the _______ ______ ______ caused by the death of _______ secreting cells.
Degeneration of the central nervous system caused by the death of dopamine secreting cells.
Dopamine is a ________ which transmits the signals responsible for the production of smooth and purposeful movements. the ________, therefore, causes patients to exhibit the symptoms people with ________ ________ suffer. (severe tremors, unstable posture, slow movements, etc)
Dopamine is a neurotransmitter which transmits the signals responsible for the production of sooth and purposeful movements. the absence, therefore, causes patients to exhibit the symptoms people with Parkinson’s disease suffer. (severe tremors, unstable posture, slow movements, etc)
Type I diabetes:
________ diabetes due to a malfunction of the ________ cells in the pancreas which causes a decrease in the secretion of ________.
Type I diabetes:
Juvenile diabetes due to a malfunction of the islet cells in the pancreas which causes a decrease in the secretion of insulin.
How are stem cells used to treat illnesses? (1 pt)
They are therapeutic options to replace damaged cell types which aren’t self-renewal with functioning cells.
What are stem cells? (1 pt, 2 ex)
unspecialized cells with 2 unique qualities
- self-renewal (continuous replication/division)
- Potency (can differenciate into other cells)
What are the different types of stem cells? (4 pts)
- Totipotent
- Pluripotentent
- Multipotent
- unipotent
What is a Totipotent stem cell? (1 pt, 1 ex)
A stem cell which can differenciate into any type of cell AND placental tissue e.g., Zygotes
What is a Pluripotentent stem cell? (1 pt, 1 ex)
A stem cell that can turn into any cell type e.g., embryonic stem cells
What is a Multipotent stem cell? (1 pt, 1 ex)
A stem cell that can turn into a number of closely related cells e.g., Haemapoeitic adult stem cells
What is a unipotent stem cell? (1 pt, 2 ex)
A stem cell that can’t differenciate but can self renew e.g., progenitor cells, muscle stem cells, etc.
What are the uses of stem cells? (2 pts)
- embryonic development
- therapeutic options to replace damaged cell types which aren’t self renewal
Where do you get stem cells? (3 pts)
- The patient’s own cells / tissues / donated tissues from another person
- The foetal umbilical cord (blood)
- Early-stage embryos specially created using Somatic cell nuclear transfer (SCNT)
How do cells differenciate? (1 pt)
By expressing a certain cell type-specific gene
Prokaryotic cells characteristics;
- DNA in a ____ forms without _____
- DNA free in the _____ (Nucleoid region)
- Mitochondria ____
- ___ ribosomes
- no internal _______ to form ______
- size less than __ μm
Prokaryotic cells characteristics;
- DNA in a ring forms without protein
- DNA free in the cytoplasm (Nucleoid region)
- Mitochondria absent
- 70s ribosomes
- no internal compartmentalisation to form organelles
- size less than 10 μm
Eukaryotic cells characteristics;
- DNA with proteins as _____/chromatin
- DNA _____ within a nuclear ______ (nucleus)
- Mitochondria present
- __ ribosomes
- Internal compartmentalisation _____ to _____ many types of ______
- size ___ than 10 μm
Eukaryotic cells characteristics;
- DNA with proteins as chromosomes/chromatin
- DNA enclosed within a nuclear envelope (nucleus)
- Mitochondria present
- 80s ribosomes
- Internal compartmentalisation present to form many type organelles
- size more than 10 μm
What are the similarities between Eukaryotic and prokaryotic cells? (3 pts)
- both have outside boundaries that always involves a plasma membrane
- both carry out all functions of life
- DNA is present in both