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
A Blastula is an early stage of ______ ______ in animals. It is produced by ______ of a fertilized ovum and consists of a spherical layer of around ______ cells surrounding a central fluid-filled cavity called the ______.
An early stage of embryonic development in animals. It is produced by cleavage of a fertilized ovum and consists of a spherical layer of around 128 cells surrounding a central fluid-filled cavity called the blastocoel.
What is an autosomal cell? (1 pt)
regular cells (non-sex cells)
what are the different types of cell division? (2 pts)
meiosis and mitosis
Mitosis:
___ phase of cell cycle. usually happens exclusively to ___ cells.
Happens during ______ repair and ______.
Where ______ and specialization occur when forming new cells.
produces identical ______ cells
Mitosis:
M phase of cell cycle, usually happens exclusively to autosomal cells.
Happens during tissue repair and growth.
Where differentiation and specialization occur when forming new cells.
produces identical daughter cells
What is the outermost part of a plant cell? (1 pts)
cell wall of cellulose
what is a gamete? (1 pt, 2 ex)
a sex cell (egg and sperm cells)
chromosomal alignment ensures mitotic fidelity by promoting ______ compaction during anaphase. During mitosis, chromosomes align at the ______ ______ to establish a metaphase plate
chromosomal alignment ensures mitotic fidelity by promoting interchromosomal compaction during anaphase. During mitosis, chromosomes align at the spindle equator to establish a metaphase plate
What is a cyclin (2 pts)
any of a group of proteins active in controlling the cell cycle and in initiating DNA synthesis.
the role of cyclins in cell division:
- Cyclins control different stages of the ______ ______
- ______ of each cyclin rise and fall in each stage, activates proteins
- The activated proteins carry out reactions that allow the cell cycle to continue
the role of cyclins in cell division:
- Cyclins control different stages of the cell cycle
- Concentrations of each cyclin rise and fall in each stage, activates proteins
- The activated proteins carry out reactions that allow the cell cycle to continue
What are the features of a prokaryotic cell? (6 pts)
- cell wall
- plasma membrane
- flagella
- pili
- ribosomes
- nucleoid region
What are the organelles of a eukaryotic cell? (9 pts)
- smooth/rough ER
- ribosomes
- lysosomes
- Golgi apparatus
- mitochondria
- nucleus
- chloroplast
- centrosomes
- vacuoles
What is the role of the cell wall in a prokaryotic cell? (2 pts)
The peptidoglycan cell wall protects and maintains the shape of the cell.
What is the role of the pili in a prokaryotic cell? (2 pts)
Attachment and joining bacterial cells in preparation for DNA transfer to one another (sexual reproduction)
What is the role of the flagella in a prokaryotic cell? (1 pts)
allows cell to move
What is the role of the nucleoid region in a prokaryotic cell? 3 pts
contains a single, long, continuous, circular thread of DNA. Involved with cell control
During ______ ______ DNA is copied, two daughter chromosomes become ______ to different regions of the ______ ______, cells divide into 2 genetically identical daughter cells
During binary fission DNA is copied, two daughter chromosomes become attached to different regions of the plasma membrane, cells divide into 2 genetically identical daughter cells
Describe the role of the endoplasmic reticulum (1 pts)
Transports materials between organelles
Describe the role of the ribosomes (1 pt)
Site of polypeptide synthesis (DNA translation)
Describe the role of the lysosomes (1 pt)
Breakdown / hydrolysis of macromolecules
Describe the role of the Golgi apparatus (2 pts)
Involved in the sorting, storing, modification and export of secretory products
Describe the role of the mitochondria (1 pts)
Carries out the reactions of the Krebs cycle/aerobic respiration
Describe the role of the chloroplast (2 pts)
Site of photosynthesis – manufactured organic molecules are stored in various plastids