What is an indicator?
- a chemical that changes colour depending on if it is in an acid or a base
eg. litmus is red in acid and blue in base
Give the correct chemical formula for magnesium fluoride.
Give the chemical formula for diphosphorous pentoxide.
Explain the different characteristics between an acid and a base.
- produce H+ when dissolved in water
- reacts with metals
- reacts with carbonates
- turns litmus red
- produce OH- when dissolved in water
- turns litmus blue
- eg. NaOH
Explain the difference between molecular and ionic compounds. Include examples.
- metal and non-metal
- usually hard, no odour, dissolves, conduct, high m.p.
- eg. NaCl
- gives/takes electrons
- 2 non-metals
- usually soft, odour, does not dissolve or conduct, low m.p.
- eg. H2O
- shares electrons
Which type of mirror always produces a virual image?
Give the characteristics of an image in a plane mirror.
Attitude: upright, laterally inverted
Location: same distance behind the mirror
Give the characteristics of an image that is formed from an object placed between C and F of a concave mirror.
Location: beyond C
Give the characteristics of the image produced when an object is placed in front of F in a concave mirror.
Location: behind mirror
Give the charateristics of an image formed from an object placed beyond 2F' in front of a converging lens.
Location: Between F and 2F
What is a biopsy?
- surgically removing a sample of tissue to look at it under a microscope
Explain the difference in structure and function between arteries, veins and capillaries.
Arteries – carry blood away from the heart
- have thick, elastic walls to withstand the high pressure of the blood moving through them
Veins – carry blood towards the heart
- have a large capacity but thinner walls since blood flows with a lower pressure
- have valves to prevent back-flow of blood
Capillaries – tiny blood vessels that connect arteries and veins
- so small, only 1 cell can move through at a time
- walls are very thin so oxygen and nutrients can diffuse from the blood into cells and wastes from cells back into the blood
What is the function of the gall bladder?
- store bile that is necessary for the digestion of fats
Describe what a cell would look like if it had 6 chromosomes and was going through anaphase of mitosis.
six individual chromatids would be moving to each pole of the cell
What is a stem cell? Where do they come from? Why is there such a controversy over their use? What is the Catholic Church's opinion on stem cell research?
- undifferentiated (nonspecialized) cells that can give rise to any type of cell and have the unique ability to reproduce themselves indefinitely
- can be obtained from adults from bone marrow, blood, muscle tissue, living of the digestive tract, brain and retina of the eye. Other sources of stem cells include aborted fetuses, unused embryos from in-vitro fertilization treatments and cord blood. Cord blood is the blood left in the placenta and umbilical cord following a birth.
- major controversy is the use of embryonic stem cells because harvesting them required the destruction of the embryo which many consider immoral
- Catholic Church has no problem with adult stem cell research however, it is opposed to embryonic stem cell research as it requires destruction of embryo
Why is the natural greenhouse effect important?
- keep the Earth warm enough to support life
What is the greenhouse effect?
- process whereby gases and clouds absorb infrared radiation emitted from the Earth's surface and radiate it, heating the atmosphere and the Earth's surface
What is albedo? Explain with examples.
Albedo refers to how much a substance reflects the sun's energy. Ice and snow have high albedos while grass and dirt have low albedos.
What is thermohaline circulation?
Transfer of energy though the hydrosphere. The cold salty water is more dense and sinks. The warmer surface water flows to take its place.
List the 6 main greenhouse gases and where they come from.
Carbon dioxide (CO2) – coal fired power plants, automobiles, natural gas, deforestation, producing cement, fertilizer production
Methane (CH4) – garbage, livestock, melting permafrost, coal fired power plants, automobiles
Nitrous oxide (N2O) – fertilizers, coal fired power plants, cars, burning forests, crop residues
Water vapour (H2O) - increase in volume with warmer temperatures
Ozone (O3) – car exhaust, pollution from factories
Fluorinated gases (CFCs and sulfur hexafluoride) – electricity grid, factories, refrigeration systems, fire suppression systems, aerosol propellants, cleaning solvents
Do you have more human cells or bacterial cells in your body?
bacterial cells (approximately 10x more)
How long would it take a blood cell to make one complete circuit of the body?
How many bones in the human body?
If you drilled a tunnel straight through the Earth and jumped in, how long would it take you to get to the other side?
42 minutes and 12 seconds
How do butterflies taste a leaf?