Biology Test Week 6 Term 1 6/3/25 Flashcards
Which features are found in both eukaryotic animal cells and eukaryotic plant cells?
Mitochondria
Which improvement has electron microscopy brought to Biology since light microscopy?
Images with a greater resolution are produced
Which of the following organelles are not found in multicellular plants?
Cilia only
The image of a chloroplast on an electron micrograph is 21mm. The true size of the chloroplast
is 4 µm What is the magnification of the image of the chloroplast?
5250x
Explain the importance of plasma membranes in eukaryote cells.
They create distinct parts of the cells, Compartmentalisation.
They separate the contents of the cell from the external medium.
or
They separate the contents of an organelle from the cytoplasm.
The sepâration allows the maintenance of the internal environment of the cell / organelle.
They provide a surface got the attachment of proteins and enzymes, e.g. to link reactions.
Describe the composition of the rough endoplasmic reticulum and its function
- The RER is made from ribosomes attached to a (hollow) membrane.
- Ribosomes are the site of protein synthesis / translation of mRNA.
- The membrane holds the ribosomes in place.
Proteins that are made enter the membrane or the membrane space. - Proteins within the membrane are transported to the Golgi body (in vesicles).
What is the difference between Bacillus and Staphylococcus?
Bacillus is rod-shaped like E.coli and Staphylococcus is spherical
In eukaryotes, what does the cell wall do? (all these questions are in eukaryote cells
Cell wall provides the cell with strength and support, prevents the cell from bursting
What does the nucleus do?
Chromosomes associated with histone proteins are located in the nucleus. It has a double membrane with pores which allow mRMA to enter the cytoplasm
What does the cytoplasm?
Most of the metabolism that occurs in the cell occurs in the cytoplasm. The cytoplasm is mostly composed of water
What does the plasma membrane do?
Controls what enters and exits the cell, composed of phospholipids
What is the difference between 70S and 80S
They are both responsible for protein synthesis. 70S is small and are involved in protein synthesis in bacteria and 80S is bigger located in the cytoplasm of eukaryotic cells, and participate in the synthesis of a wide range of proteins.
What is the nucleiod region?
Contains a single circle chromosome. Chromosome contains DNA (no protein) contains the genetic info for the growth and development of the cell
