Super Ultimate iGCSE biology revision crossword

12345678910111213141516171819202122232425262728293031323334353637383940414243
Across
  1. 2. membrane-bound organelle containing genetic material DNA that regulates gene expression and cell activities
  2. 6. a detectable change in the internal or external environment that triggers a response
  3. 7. action a rapid involuntary response to a stimulus involving a reflex arc
  4. 9. a microscopic blood vessel with a one cell thick wall allowing efficient exchange of substances between blood and tissues
  5. 10. the net movement of water molecules across a partially permeable membrane from a region of higher water potential to lower water potential
  6. 11. a sequence of DNA that codes for a specific protein or functional RNA
  7. 12. transport the movement of substances against their concentration gradient using energy from ATP via carrier proteins
  8. 14. the process by which light energy is converted into chemical energy to synthesise glucose from carbon dioxide and water
  9. 18. the net passive movement of particles from a region of higher concentration to lower concentration down a concentration gradient
  10. 20. a physiological or behavioural change resulting from a stimulus
  11. 22. an organism that synthesises organic compounds from inorganic substances using an external energy source
  12. 23. organelle where aerobic respiration occurs, producing ATP through oxidative phosphorylation
  13. 25. site of protein synthesis where mRNA is translated into polypeptide chains
  14. 26. a blood vessel with thinner walls and valves that returns blood to the heart under lower pressure
  15. 27. a blood vessel with thick elastic walls that carries blood away from the heart under high pressure
  16. 29. a biological catalyst typically a protein that increases the rate of chemical reactions without being consumed
  17. 30. an allele that is expressed in the phenotype even when only one copy is present
  18. 34. a specialised subcellular structure with a specific function, often membrane-bound in eukaryotic cells
  19. 35. vascular tissue composed of dead cells that transports water and mineral ions from roots to the rest of the plant and provides structural support
  20. 36. a dynamic system of interactions between a community of organisms and their physical environment
  21. 37. the straw coloured liquid component of blood that transports cells nutrients hormones and waste products
  22. 38. the smallest structural and functional unit of an organism capable of carrying out all vital processes
  23. 41. an iron containing protein in red blood cells that reversibly binds oxygen for transport
  24. 42. the fusion of the nuclei of male and female gametes to form a diploid zygote
  25. 43. living vascular tissue that translocates organic nutrients particularly sucrose throughout the plant
Down
  1. 1. a junction between two neurons where chemical neurotransmitters transmit signals
  2. 3. the specific reactant molecule upon which an enzyme acts
  3. 4. the mechanical and chemical breakdown of large insoluble molecules into smaller soluble molecules
  4. 5. an allele that is only expressed in the phenotype when two copies are present
  5. 8. a diploid cell formed after fertilisation that undergoes mitotic division to develop into an organism
  6. 12. the movement of digested soluble molecules across cell membranes into the bloodstream or lymph
  7. 13. a series of metabolic reactions that release energy from glucose to produce ATP
  8. 15. a chemical messenger secreted by endocrine glands and transported in the bloodstream to target organs
  9. 16. a specialised cell adapted to transmit electrical impulses
  10. 17. microscopic pores in the epidermis of leaves that regulate gas exchange and water loss
  11. 18. an organism that breaks down dead organic matter releasing nutrients back into the ecosystem
  12. 19. chain a linear sequence showing the transfer of energy between organisms through feeding relationships
  13. 21. aqueous medium containing enzymes where most metabolic reactions occur
  14. 24. organelle containing chlorophyll where photosynthesis takes place
  15. 27. an alternative form of a gene found at the same locus on homologous chromosomes
  16. 28. a group of organisms of the same species living in a defined area at a given time
  17. 31. an organism that obtains energy by feeding on other organisms
  18. 32. membrane selectively permeable phospholipid bilayer that regulates the movement of substances into and out of the cell
  19. 33. a haploid reproductive cell that fuses with another during fertilisation
  20. 39. photosynthetic pigment that absorbs light energy mainly in the red and blue wavelengths
  21. 40. site the region of an enzyme with a specific shape complementary to the substrate where binding and catalysis occur
  22. 41. the natural environment in which an organism lives and to which it is adapted