1Microtubules and microfilaments are part of the cytoskeleton
Suggest two roles of the cytoskeleton in the type of cell shown in (fig 5.1) (2)
- provides, strength / stability / support (cell);
- determines shape / changes shape / moves membrane (for endo/ exocytosis);
- movement of, organelles / named organelle / RNA / protein / chromosomes / chromatids;
- attachment to / hold organelles / named organelle, in place;
- make up, centrioles / spindle fibres
2Fig (1.1) is a diagram of. bacterium as seen under an electron microscope
Name the structures labelled A and B (2)
A = plasma / cell surface, membrane;
B = DNA / chromosome / chromatin / genetic material;
3Fig (1.1) is a diagram of. bacterium as seen under an electron microscope
It has been suggested that the mesosome has the same role as mitochondria in eukaryotic cells
Suggest the role of the mesosome in prokaryotic cells, such as bacteria (1)
production of ATP;
AEROBIC respiration;
4Eukaryotic cells, such as Euglena, contain membrane-bound organelles. Each organelle has a specific function in the cell
State the process that is carried out in each of the organelles listed below
ribosome:
chloroplast: (2)
5Explain why a single-celled organism, such as Euglena, does not need a specialised area to carry out gaseous exchange (2)
- large surface area to volume ratio;
small so demand for, O2 / CO2 is low;
idea of: DIFFUSion (alone) is adequate to meet needs;*
6The mammalian gas exchange system contains a variety of types of cells and tissues
Complete (table 1.1), stating the function of each of the cells and tissues. The first row has been completed for you (4)
squamous epithelium = to provide a thin surface for a short diffusion distance
elastic tissue
ciliated epithelium
goblet cells
smooth muscle
elastic tissue = recoil OR return to original, size / shape OR to help expel air OR prevents alveoli bursting;
ciliated epithelium = waft / wave / move, mucus;
goblet cells = secrete / release / produce, mucus;
smooth muscle = constrict the airway;
7(fig 4.1) shows diagrams of two different types of cells, X and Y
The cells are not drawn to scale
State, using only the information in (fig 4.1), two differences between plant cells and animal cells (2)
plant cell / Y has:
a wall;
chloroplasts;
vacuole;
8Cell Y is a guard cell
State, using only the information in (fig 4.1), one adaptation of this cell and explain how the adaptation allows the cell to carry out its function (2)
A1 a vacuole;
E1 to take up water / to become turgid;
A2 cell wall thicker on one side;
E2 causes, cell to bend / open stoma(ta);
A3 mitochondria;
E3 generates ATP (for active transport);
9(fig 4.2) shots drawings of the six chromosomes inside an animal cell viewed during late prophase of mitosis