everything Flashcards
parts of an Animal Cell
nucleus, cytoplasm, cell membrane, ribosomes, mitochondria
parts of a Plant Cell
nucleus, cell membrane, cytoplasm, cell wall, vacuole, chloroplast, ribosomes, mitochondria
parts of a Fungal Cell
nucleus, cytoplasm, vacuole, cell membrane, ribosomes, cell wall, mitochondria, bud scar
parts of a Bacteria Cell
cytoplasm, plasmids, capsule, cell wall, cell membrane, ribosomes, DNA
what does the cell membrane consist of?
Phospholipids and proteins
The cell membrane is selectively permisable. what does this mean?
This means that only certain substances can pass through it.
what substances that can pass through the membrane?
Starch, amino acids, glucose, proteins
What substances cannot pass through the membrane?
fatty acids, oxygen, red blood cells.
What is diffusion?
is the movement of molecules from an area of high concentration to an area of low concentration, down a concentration gradient.
Does diffusion require energy
it does not require energy
What is meant by a concentration gradient
A concentration gradient is the difference in concentration of molecules between one area compared to another.
Why is diffusion important to cells?
It allows cells to gain useful substances they require to obtain energy, grow and lets them get rid of waste products.
Definition of Osmosis?
Osmosis is the movement of water from an area of high water concentration to an area of low water concentration, across a selectively permeable membrane.
why does osmosis affect animal and plant cells differently?
Because plant cells contain a Cell Wall.
What is Active Transport?
is movement of molecules and ions from a low concentration to a high concentration, against a concentration gradient.
Where does the energy for active transport come from?
Respiration. The energy comes from a special energy-rich molecule called ATP (adenosine triphosphate).
How is active transport carried out?
by carrier proteins in the membrane, called pumps.
What is DNA?
DNA is a double- stranded helix molecule, held together by complementary bass pairing.
Definition of DNA?
DNA carries the genetic information for making a protein.
Definition of a gene?
A gene is a section of DNA which codes for a protein.
What are the 4 bases called?
adenine, thymine, cytosine, guanine.
What is the base pairing rule?
A-T
C-G
What are proteins made from?
Amino Acids
What does the base sequence determine?
determines the amino acid sequence in proteins.
What is the messenger RNA?
is a molecule which carries a complementary copy of the genetic code from the DNA, in the nucleus, to a ribosome, where the protein is assembled from amino acids.
what are amino acids joined together with?
peptide bonds
Proteins have many functions such as….?
structural, enzymes, hormones, antibodies and receptors
How do enzymes function?
as biological catalysts and are made by all living cells
What do enzymes do?
they speed up cellular reactions and are unchanged in the process.
How many substrates do enzymes work on?
one
The shape of the active site of an enzyme molecule is?
Is complementary to its specific substrate.
What can enzymes be involved in?
in degradation(break down) and synthesis (build up) reactions.
how can enzymes be used in biotechnology industries?
For making cheese, washing powders.
how can enzymes be used to make cheese?
they speed up the clotting process of milk.
how can enzymes be used in washing powders?
to help break down stains
How are enzymes used in digestion?
to break down food into basic units
What are the basic unit(s) for carbohydrates?
glucose
What are the basic unit(s) for fats?
Fatty acids and Glycerol
what are the basic unit(s) for proteins?
amino acids
What can enzymes and other proteins be affected by?
temperature and PH
when is each enzyme most active?
in its optimum conditions
At low temperatures enzyme activity is…?
slow
At temperatures above 37 degrees enzymes are often…?
denatured
Explain what is meant by the term optimum PH?
each enzyme is most active in its optimum conditions
explain the meaning of the term optimum temperatures?
The conditions at which an enzyme is most active
Explain the meaning of the term denatured?
The substrate no longer fits and so the enzyme does not function.
how can genetic information be transferred from one cell to another naturally or artificially?
by genetic engineering
What can two bacterial cells that join together exchange?
bacterial plasmids
what happens if viruses infect living cells?
they insert their genetic information into the nucleus of their host.
what is genetic engineering?
is the transfer of DNA from one organism to another using biotechnology.
what is the organism receiving the DNA said to be?
genetically modified (GM)
why can bacterial cells be genetically modified?
so that they have the gene for producing human insulin.
what is genetic engineering a form of?
gene therapy
The chemical energy stored in glucose must be released by all cells through a series of enzyme-controlled reactions called…?
respiration
Methods that can cause respiration experiments several drawbacks?
- heat is lost to the surroundings
- the heat that reaches the water is not evenly distributed
- the food does not burn completely to ashes
A calorimeter can be used instead to give more accurate energy values.
It is better because?
- oxygen is added to make sure the food burns completely.
- The stirrer and coiled chimney spreads the heat evenly throughout the water.
- The food enclosed therefore loss of heat energy is reduced to a minimum.
the energy released from the breakdown of glucose is used to generate what?
ATP (adenosine triphosphate)
where is the highest concentration of carbon dioxide found in the lungs?
In the cupillary surrounding
Is diffusion passive or active?
passive
what two components is the plasma membrane made from?
phospolipids and protein
where in the cell is the energy produced?
mitochondria
so what is the process of which energy is produced?
respiration
how many bases code for one amino acid?
3 bases
what are the building blocks of proteins?
amino acids
what are humans aiming to make with genetic engineering?
a protein we want
what organisms are we using for genetic engineering?
bacteria
what is removed from a bacteria?
A plasmid
what is a plasmid made of?
DNA
How is it possible for a gene to fit in?
As all DNA is made of the same 4 bases.
Name a cellular processes which requires energy from ATP?
Muscle contraction, cell division, protein synthesis, transmission of nerve impulses, active transport, carbon firation
