Unit 1- Cell Biology NEED TO KNOW Flashcards
Which cell does not have a cell wall?
Animal cell
What are plant cells made of?
Cellulose
What is found in a plant cell?
Cell wall Mitochondria Chloroplast Cell membrane Cytoplasm Vacuole Nucleus Ribosomes
What is found inside an animal cell?
Cell membrane Mitochondria Ribsome Cytoplasm Nucleus
What is found in a fungi cell?
Cell wall Cell membrane Cytoplasm Ribosomes Mitochondria vacuole Nucleus
What is found in a bacterial cell?
Cell wall Cell membrane Ribosomes Cytoplasm Plasmid
What does the cell membrane consist of?
Phospholipids and proteins and is selectively permeable
What is passive transport?
Movement of molecules down a concentration gradient and DOES NOT require energy
What is osmosis?
Osmosis is the movement of water molecule through a selectively permeable membrane, from an area of high concentration to low concentration.
What can happen to animal cells?
They can burst or shrink
What can happen to plant cells?
Become turgid or plasmolysed
Why does active transport require energy?
For membrane proteins to move molecules and ions against the concentration gradient.
What are body cells?
Diploid and have 2 sets of chromosomes
What is cell division called?
Mitosis
What is mitosis required for?
Growth and repair
What happens at the start of mitosis?
Chromosomes are made up of 2 chromotids.
Chromosomes line up at the?
Equator
Examples of aseptic techniques?
Washing hands
Safety goggles
Lab coat
Clean surface before and after starting
Cell culturing requires a?
Appropriate medium and the control of other factors like oxygen concentration, temperature and pH
What does DNA carry?
Genetic information for making protein
What shape is DNA
Double stranded helix held by complementary base pairs
What are the four bases, and which ones are complementary to whom?
Adenosine Thymine Guanine Cytosine A-T G-C
What does the base sequence determine?
The amino acid sequence in the protein
What is messenger RNA (mRNA)?
A molecule which carries a complementary copy from the DNA, in the nucleus to a ribosomes, where the protein is assembled from amino acids.
What are enzymes?
Biological catalysts which are made by all living cells.
What are enzymes involved in?
Synthesis and degradation reactions.
Examples of proteins?
Structural, enzymes, hormones, antibodies and receptors.
What do enzymes do?
Speed up reactions, are unchanged in the process and always produce the same products.
The enzymes active site is?
Complementary to a specific substrate
When do enzymes work best?
In its optimum conditions
How are enzymes affected?
Temperature and pH
What can happen when an enzyme is denatured?
The active site changes shape and can no longer fit it’s specific substrate.
How can genetic information be transferred from one cell to another?
Through genetic engineering
What are the stages of genetic engineering?
Identify the section of DNA in the source chromosome that contains the required gene, extract the required gene, extract the vector/ bacterial plasmid, insert the plasmid into host cell and grow the modifies cells to produce a GM organism.
Are enzymes required in genetic engineering?
YES
What is the equation for photosynthesis?
Carbon dioxide + water + light energy ———> sugar (glucose) + oxygen
What is the name of stage one of photosynthesis?
Light reactions
What is he name of stage two of photosynthesis?
Carbon fixation
Where is the light energy trapped in stage one of photosynthesis?
In the plants chlorophyll is the chloroplast
What is light energy converted into?
Chemical energy in the form of ATP
In photosynthesis, what is water split into?
Hydrogen and oxygen
What diffuses as a waste product in the first stage of photosynthesis?
Oxygen
How is hydrogen transferred to stage two of photosynthesis?
Attaches to a hydrogen acceptor molecule
Limiting factors of photosynthesis?
Temperature
Light intensity
Carbon dioxide
What happens at the carbon fixation stage?
A series of enzyme controlled reactions, which use hydrogen and ATP produced by the light reactions, together with carbon dioxide, to produce sugar.
What can the chemical energy in sugar be used for?
For respiration or can be converted into other substances such as starch or cellulose
What is respiration?
Is a set of enzyme controlled reactions which releases chemical energy in a glucose molecule.
The energy released from the breakdown of glucose is used to make?
ATP from ADP and inorganic phosphate (Pi)
Know the equation
ADP + Pi + energy —–> ATP
The energy released from respiration can be used for?
Mitosis, muscle contraction, protein synthesis and transmission of nerve impulses
In respiration what is glucose broken down into?
Pyruvate and then to carbon dioxide and water IF OXYGEN IS PRESENT
Breakdown of glucose in the presence of oxygen produced how many molecules of ATP?
38!!!!
If oxygen is absent what takes place?
Fermentation
How many molecules of ATP does fermentation produce?
2!!
Fermentation in animal cells, glucose if broken down into what?
Lactic acid
the glucose in fermentation I’m plants is broken down into what?
Ethanol and carbon dioxide
Where does respiration take place?
In the cytoplasm and the process of fermentation is completed in the cytoplasm
Where does AEROBIC respiration start and finish?
Starts in the cytoplasm and is then completed in the mitochondria
How do you measure the rate of respiration?
Repirometers
What is the definition of diffusion?
The movement of substances from a region of high concentration of that substance to a region of low concentration until the concentration becomes equal.
Meaning of turgid?
Swollen and hard. It takes up water by osmosis but the cell wall prevents it from bursting and the cell hardens.
This is what makes the green parts of the leaf stand up in the sun light.
What is meant by plasmolysed?
When plant cells are placed in concentrated sugar solutions, they lose water by osmosis. They are said to be flaccid, this is the exact opposite of turgid. The contents of the cell have began to shrink and this is said to be plasmolysed
