Biology 101 Flashcards
State the two main reasons why food is required by all living organisms.
Energy
Growth
What is the ratio of hydrogen atoms to oxygen atoms in a carbohydrate?
2:1
Give a structural role of lipids in cells.
It is a component of cell membranes.
Give a metabolic role of lipids in cells.
As a source of energy
Give an example of a fat‐soluble vitamin.
Vitamin D
Vitamin E
Vitamin K
Vitamin A
Name a disorder due to a dietary deficiency of the vitamins ; A, D, E and K.
Vitamin D - Osteomalacia or Osteoporosis
Vitamin E - Anaemia
Vitamin K - Easy Bruising
Vitamin A - Night Blindness
What is meant by the term hypothesis?
This is an educated guess based on observations
Explain what is meant by double‐blind testing.
This is a form of testing whereby neither the tester nor the subject knows who gets the drug (or who gets the placebo)
Explain the necessity for random selection.
for a fair test and for unbiased results
Give two other features of good experimental design.
A control/ only one variable/ safe (procedure)/ large sample size/ repeatable/ replicates
Where are the results of scientific research usually first published?
Scientific Journal
Why is it important that scientists publish the results of their research?
So that others can learn (from their work)
So others can repeat it
Information made widely available
What is meant by the term tissue?
A group of cells working together to carry out a similar function.
Name two types of animal tissue.
Epithelial (or epidermis)/ muscle/ connective/ nervous/ adipose/ blood/ bone/ cartilage/ tendon/
ligament
What is meant by the term tissue culture?
Growth of cells in vitro
Give one other application of tissue culture.
Plant breeding/ micro-propagation/ plant propagation/ vegetative propagation/ skin grafts/ cancer research/ IVF/ vaccine production/ antibody production/ replacement organs
Which type of microscope is used in the school laboratory to observe cells?
Light Microscope
Give two observable events that happen during prophase.
Nuclear membrane disappears
Chromosomes are visible
After mitosis, what happens in animal cells?
A cleavage is formed
After mitosis, what happens in plant cells?
A cell plate is formed
What word is used to describe the shape of the two faces of the red blood cells?
Biconcave
What feature of red blood cells allows them to pass through the narrow capillaries?
They are flexible
Name the molecule in red blood cells that carries oxygen.
Haemoglobin
Human red blood cells live for about 120 days.
Give a reason for this, based on the composition of these cells.
No nucleus or no mitochondria or no organelles or cannot reproduce
Give a location in the body where red blood cells are produced
Bone Marrow
Give a location in the body where red blood cells are usually broken down.
Liver or Spleen
Name the transport fluid in humans that does not contain red blood cells.
Lymph
Name the blood vessel from which the capillary arises.
Pulmonary artery (arteriole)
Give any three features of alveoli or their capillaries that allow for efficient gas exchange.
The alveoli’s membrane (or wall) is thin / it has a Large surface area/ Large numbers/ Moist surface/
Name a disorder of the human breathing system and suggest how it is caused and treated.
Asthma
caused by dust or allergens
treated using an inhaler.
What is the use of a Biuret Reagent
to test for protein
What is the use of Benedict’s solution
to test for reducing sugar
When preparing a sample of cheek cells on a microscope slide, why did you place a coverslip over the cells?
To prevent (the cells) from drying out or to protect the (objective) lens (from water or from stain) or to hold sample in place or easier to see
When preparing a sample of cheek cells on a microscope slide, why did you apply methylene blue to the cells?
To stain (the cells) or to make (the cells) easier to see
When extracting DNA from plant tissue, why did you use washing up liquid?
To breakdown the cell membrane
When extracting DNA from plant tissue, why did you use freezer‐cold ethanol?
To precipitate (the DNA) or to make (the DNA) insoluble or take (the DNA) out of solution or to make (the DNA) visible
When using seeds to investigate the effect of IAA on plant tissue, why did you carry out a serial dilution of an IAA solution?
(To make solutions of) different concentrations (of IAA)
When using seeds to investigate the effect of IAA on plant tissue, why did you place the seeds on a grid in Petri dishes?
To measure the growth (of root or shoot accurately)
When carrying out an activity to investigate osmosis why did you use Visking tubing?
To act as a selectively permeable membrane or to mimic the plasma membrane
When carrying out an activity to investigate osmosis how did you know osmosis had taken place?
Mass of tubing increased (or decreased) or tubing got fuller (or less full) or increased turgidity
Is oxygen necessary for fermentation?
No