B1 Flashcards
(28 cards)
How do you work out the total magnification on a microscope?
Eyepiece lens magnification X objective lens magnification
How do you work out the image size?
Magnification X real size
What is the word equation
for aerobic respiration?
Glucose + oxygen -> carbon dioxide +water
List four features that animal and plant cells have in common
Cell membrane, cytoplasm, mitochondria and nucleas
Give two sub-cellular structures that are present in prokaryotic cells but not eukaryotic cells
Plasmids and chromosomal DNA
How have electron microscopes been able to increase our understanding of sub-cellular structures?
They have let us see much smaller things in more detail (like the internal structure of mitochondria)
Why is it important to take a thin slice of a sample before viewing it under a light microscope?
So light can be let through it allowing you to see it clearly
Give the initials of the four bases present in DNA
G,C,A,T
Describe the structure of a nucleotide
The base is attached to the sugar which is attached to the phosphate. The base is the only part of the molecule that varies.
What is a gene?
A section of DNA that codes for a particular protein
What is the triplet code?
The three bases (in the gene) in a particular sequence that code for an amino acid
What is the process of making mRNA from DNA called?
Transcription
In what part of a cell are amino acids joined together to form a protein?
Cytoplasm
What does it mean when an enzyme has been denatured?
The bonds holding the enzyme together have been broken due to high temperatures
Give two things that you could measure when investigating the rate if an enzyme-controlled reaction
Measure how fast a product appears (how much oxygen produced in a certain time) or how fast a substrate disappears (time taken for starch to break down to maltose so iodine remains browny-orange instead of turning blue-black)
Give two variables that need controlling when investigating the effect of pH on an enzyme-controlled reaction
Temperature, potato (starch) used
What is respiration?
The process of transferring energy from the breakdown of glucose
Is respiration an exothermic or endothermic reaction?
Exothermic (transfers energy into the environment in the form of heat)
Name the type of respiration that requires oxygen
Aerobic
Give an example of when lactic acid would be produced as a product of respiration
During vigorous exercise
Which form of respiration transfers more energy per glucose molecule?
Aerobic
Briefly describe an experiment to show that carbon dioxide is a product of respiration
Two test tubes;
Test tube A germinating beans- respiring
Test tube B boiled beans - dead so not respiring
Beans above hydrogen-carbonate indicator on gauze
Respiring beans produce CO2 so indicator turns yellow
What type of polymer do you get when you join together simple sugars?
Carbohydrates
Name the basic units lipids are made from
Glycerol and 3 fatty acids
