bio test (1) - 5/16/24 Flashcards
Summative Biology Quest 1: Cells, Cell Cycle, Cell Division, Specialization
What is biotechnology?
Biotechnology is the use of
biological processes to develop
new products or methods for
improving human health and
society.
What are the areas in biotechnology?
Bioinformatics: solve biological problems using computers
(e.g., the human genome project, cancer genome project)
Red Biotechnology: medical applications
Blue Biotechnology: marine/aquatic applications
Green Biotechnology: agriculture, environmental science
applications
White Biotechnology: industrial applications
What is “Cancer Genome Atlas”? What are its advantages and disadvantages?
- established in 2005
- document genetic mutation of most types of cancers
advantages: better understanding of cancer, assists in research for treatment/therapy development
disadvantages: tumour cells are processed at a single moment (we don’t have information about overall development of these cancers), there are other ways to collect info about cancers (rather than DNA)
What is “Genetic Screening”? What are its advantages and disadvantages?
- test for probability of certain hereditary diseases (e.g., Prenatal Diagnostic Test, Forensic/Identity Testing)
advantages: promotes early treatment, provides peace of mind (knowing you don’t have certain diseases)
disadvantages: expensive, can lead to false results (some diseases can still develop even if low probability is shown)
What is “Regenerative Medicine”? What are its advantages and disadvantages?
- branch of medicine that develops methods to regrow, repair or replace diseased cells/organs/tissues
advantages: potential of curing diseases/illnesses, prolong our lives
disadvantages: long-term effect is unknown, ethical issue: where do we draw the line of what can and can’t be replaced?
What are “Cell-Based Therapies? What are its advantages and disadvantages?
- forces unspecialized cells (stem cells) to turn into specific cells that need replacement
advantages: potentially powerful technique to cure many diseases and illnesses, risk of rejection is reduced (own cells are being used)
disadvantages: ethical issues; stem cells come from embyro, adult stem cells are limited, still getting researched
What is “Animal Cloning”? What are its advantages and disadvantages?
- producing identical organisms using the genes from an existing adult
advantages: can produce disease resistant animals to develop high quality herds or flocks, cloned animals can be used for biomed research
disadvantages: ethical issues (animal welfare), cloned animals develop diseases or illnesses (and die prematurely)
What is “Genetically Modified Foods”? What are its advantages and disadvantages?
- gene inserted to food plants so that the plant can have certain characteristics that consumers like
advantages: increased nutrients, productivity, food production to feed the growing populations, social stability, reduce the use of herbicides and insecticides
disadvantages: long-term effect on human health is unknown, domination of world food production, ethical issues: tampering with nature
What is “Bioremediation”? What are its advantages and disadvantages?
- genetically modified microorganisms that will breakdown harmful substances
advantages: complete destruction of contaminants is possible, carried without disruption of normal activity, less expensive
disadvantages: limited to biodegradable compounds, difficult to implement on a large scale, takes a long time to complete
What is “Gene Therapies”? What are its advantages and disadvantages?
- modified genes are re-inserted back into a patient to correct an underlying genetic problem
advantages: creates hope for many people (only way to cure certain diseases)
disadvantages: body’s immune system may reject insertion of new genes, ethical issues (design babies, superior humans)
What is the nucleus?
brain of cell, controls DNA and all activities, in both plant and animals.
also has a nuclear membrane protecting it.
What is the nucleolus?
ribosome assembly area, in both plant and animals
What are chromosomes?
where DNA is stored, in both plant and animals
What is the endoplasmic reticulum?
responsible for material movement in cell, in both plant and animals
What are ribosomes?
protein builder, in both plant and animals
What are the golgi bodies?
sort & delivery of proteins, in both plant and animals
What are the vacuoles?
waste manager/storage, in both plant and animals
What is the cytoplasm?
gel-like filling within cell, organelles can be moved around, in both plant and animals
What is the cell membrane?
enter/exiting regulator, in both plant and animals
What is the centriole?
organizes spindle fibres, structural support, animal only
What are the chloroplasts?
photosynthesis conduction → provides energy with sunlight, plant only
What are the lysosomes?
breaks down food, animal only, sometimes plants
What is the cell wall?
provides more protection; surrounds membrane. Made up of cellulose. Protects against mechanical stress and water pressure. Plant only
What is the difference between the animal cell and plant cells?
Animal cells; circular shape, only have cell membrane for protection, have centriole, small vacuole
Plant cell; have chloroplasts and cell wall (for photosynthesis and extra protection), large vacuole for water retention and rigid/rectangular shape
What is the hierarchy of structures in animals? Describe each part of it.
Stem Cells → Tissues → Organs → Organ System → Organisms
stem cells: cells that turn into specialized cells with specific functions (e.g., muscle cell)
tissues: group of specialized cells connecting together to perform a specific function
organs: group of diffdrent tissues connected together to function for a specific organ (muscle and nerve tissues make up heart organ)
organ systems: one or more organs working together to perform a system (heart organ makes up circulatory system)
What is the cell theory?
- basic units of life
- all organisms are made up of one or more
- all made from each other
- different functions (converting energy, break down sugar and proteins to digest, excreting molecules that aren’t in use, dividing/growing
Why is DNA important?
Controls many of your features 🡪 from eye colour to the ability to digest milk!
Determines how your body may function and look
Organization of DNA
Chromosome: organized and condensed DNA molecule
Chromatin: mass of very long fibers (combination of DNA and proteins)
(chromatins are what chromotids become before they condense; baby stage
Explain the structure of chromosomes
Chromatid: One copy of a duplicated chromosome
Centromere: A.K.A. Kinetochore, part of a chromosome that joins two sisters chromatids together
What are genes?
DNA is divided into segments called genes. They are responsible for controlling the production of various proteins involved in cell activities.
Explain the structure of DNA
- DNA is a double helix
- It is a long chain of repeating subunits called nucleotides
- Two strands are called “sugar-phosphate backbone”
- Middle rows are “nitrogenous bases”
What are the four types of nitrogenous bases? What is a nucleotide?
Adenine, Thymine, Cytosine, Guanine. (Nucleotides; sugar, phosphate and bases)
What is DNA coding?
- The order of base pairs; A-T, C-G are put together is in the genetic code (the code provides instructions)
- “Complementary base pairing” is when one strand is known, then the sequence of bases can be determined through the pairing
What is the cell cycle? What’s the purpose?
The cell cycle is a series of events that take place in order for a cell to grow and divide.
Purpose: Reproduction (produce offspring), growth (cell division helps organisms grow, cells divide rather than grow, if they become too large), repair (replace dead or damaged cells)
Describe each stage in the cell cycle (interphase, prophase, metaphase, anaphase, telophase, cytokinesis)
Interphase:
- Cell spends 90% of time in this stage
- G1: Cell Grows and Performs its normal functions
- S: Chromosomes are replicated in preparation cell division.
- G2: Cell continues to grow in preparation for cell division.
Prophase:
- Nuclear membrane disappears
- Centriole moves to opposite sides
- Spindle fibers begin to grow out of them and move towards the centromeres
- Chromosomes condense and thicken
- They are now made up of two identical chromatids connected by centromeres
Metaphase:
- Double stranded chromosomes align in the middle (e plate) of the cell
- Spindle fibers prepare to attach themselves to the chromosomes and pull them apart
Anaphase:
- Spindle fibers shorten and pull sister chromatids to opposite poles of cells
Telophase:
- Spindle fibers disintegrate
- Chromosomes reach opposite sides of cell
- Two nuclei are formed
- Nuclear membrane begins to reform
Cytokinesis:
- Last stage of cell cycle, not mitosis
- Cytoplasm splits in half
- Cytokinesis in: Plants: cell plate forms across cell; eventually becoming cell wall. Animals: cell membrane pinches off
After Cell Division:
- Daughter cells are formed; each with the 46 chromosomes
- Cell cycle repeats for each cell individually
How does cancer work on a cellular level?
When cells don’t stay in interphase for long enough and therefore grow/divide too fast. They take valuable nutrients from regular cells.
What is a malignant and benign tumour?
Malignant = cancerous tumour. They interfere with other tumours. Metastasis can occur.
Benign = non-cancerous tumour.
Risk factors of cancer
environmental factors (carcinogens) such as tobacco smoke, viruses, chemicals in plastic, radiation (x-rays)
What is a stem cell?
- Undifferentiated/specialized cells.
- Stem cells undergo mitosis to produce two identical daughter cells
- Depending on which genes are activated, the daughter cells may develop into different types of specialized cells
Where can you obtain stem cells?
Adult bone marrow and developing fetus
How can stem cells be used?
Generate new tissues and organs
What are the problems that exist in using stem cells?
- Manipulating calls to be specialized isn’t always possible
- Expensive
- Getting embryonic stem cells from a growing fetus/embryo can be unethical
What adult stem cells exist and how they can be used?
Can be used in regenerative medicine to regenerative medicine to replace damaged cells. Liver, muscle, skin and blood stem cells can be used; they’re all found in bone marrow.
What is differentiation?
- When unspecialized stem cells develop into specialized cells
Describe the process of: One cell –> Complex multi-cellular organism
Sperm + Egg = Zygote –> (mitosis) Blastocyst
blastocyst: hollow storage of cells; they then go through differenti
What is a specialized cell?
Specialized cells arise from stem cells through a process called cellular differentiation. They have specific functions. An organism requires different types of cells.
What is an ultrasound?
Description:
Uses ultra high frequency sound
waves to create a digital image.
Type of cancer diagnosed:
- View soft tissues such as the heart or liver
- Ovarian cancer
Risks, Limitations, Disadvantage:
- Very safe to use with pregnancy
- Disrupted by air, so it is not ideal for hollow organs
What is a CT Scan?
Description:
- Takes multiple x-rays of the body from
different angles
- Images are assembled by a computer to
form a series of detailed images
- View parts of the body that can not be
seen in a typical x-ray scan
Type of cancer diagnosed:
- Lung cancer
Risks, Limitations, Disadvantages:
- X-Rays can cause DNA damage
What is a Magnetic Resonance Imaging (MRI)?
Description:
- Use radio waves and strong magnetic fields to create an image that has more detail than a CT scan
- Computers assemble information into a 3D image
Type of cancer diagnosed:
- Brain cancer
Risks, Limitations, Disadvantages:
- No metal on patient
- Claustrophobia (lying down in a
small tube for a long period of time)
What is surgery?
Description and Advantages:
- Physically removing the cancerous tissue
Risks, Limitations, Disadvantages:
- Tumour must be easily accessible and well-defined
What is chemotherapy?
Description and Advantages:
- Treat cancer using drugs
- Works by slowing or stopping cancer cells from dividing or spreading
- Drugs can be injected or taken orally
- Can be used to shrink a tumour prior to surgery or radiation
Risks, Limitations, Disadvantages:
- Side effects include hair loss, nausea, fatigue
What is radiation?
Description and Advantages:
- Since cancer cells divide rapidly, DNA is easily damaged by ionizing radiation
- Radiation is directed at tumour by focused laser beam or implanting a radioactive source
into the tumour (minimizes effects of radiation)
Risks, Limitations, Disadvantages:
- Can damage healthy cells in the same area
- Skin problems (itching, dryness, peeling)
What is biophotonics?
Description and Advantages:
- Using beams of light to detect and treat cancer
- Allows early detection of cancer, with fewer side effects than radiation and is more accurate
Risks, Limitations, Disadvantages:
- May cause pain and swelling in nearby cells
- Expensive, limited by investment in technology
What are some sources of stem cells?
Embryonic Stem Cells:
- Found in embryo about 5 days old (called Blastocyst)
- Can differentiate into any kind of cell
Cord Blood Stem Cells:
- Found in umbilical cord connecting fetus to mother
- Can differentiate into different types of blood cells
Adult Stem Cells:
- Found in different tissues of a living organism
- Can differntiate into any type of cells
What is an endoscopy?
Description:
- A fiber optic cable that delivers light, a tiny camera, and a cable that sends images to a screen.
- Tools, such as forceps, can be attach to take cell
samples (biopsy).
- Used to look for abnormal growths.
Type of cancer diagnosed:
Colon cancer (colonoscopy)
Risks, Limitations, Disadvantages:
Patient may be given a sedative as it can be
uncomfortable.
What is a mammogram?
Description:
A specialized X-Ray Technique
Type of cancer diagnosed:
Breast Cancer
Risks, Limitations, Disadvantages:
- X-Rays can cause DNA damage
- Particularly harmful to rapidly dividing cells, like a fetus, so pregnancy is a limitation
