The krebs cycle for questions 4–7, write true if the statement is true. if the statement is false, change the underlined word or words to make the statement true. 4. the pyruvic acid produced in glycolysis enters the chloroplasts if oxygen is present in a cell. 5. in the matrix, pyruvic acid is converted to lactic acid before the krebs cycle begins. 6. the compound that joins with a 4-carbon molecule in the krebs cycle is called acetyl-coa. 7. carbon dioxide is the only product of the krebs cycle that is not re- used or used in other stages of cellular respiration.

What is the difference between cytokinesis in plant and animal cells? animal cells dived by a cleavage furrow. plant cells divide by a cell plate that eventually becomes the cell wall. cytoplasm and cell membranes are necessary for cytokinesis in both plant and animals.

Proteins are the workhorses of the cell, controlling virtually every reaction within as well as providing structure and serving as signals to other cells. proteins are long chains of  amino acids  , and the exact sequence of the amino acids determines the final structure and function of the protein. instructions for that sequence are encoded in  genes  . to make a particular protein, a messenger ribonucleic acid (mrna) copy is made from the gene (in the process called  transcription  ), and the mrna is transported to the  ribosome  . protein synthesis, also called  translation  , begins when the two ribosomal subunits link onto the mrna. this step, called initiation, is followed by elongation, in which successive amino acids are added to the growing chain, brought in by transfer rnas (trnas). in this step, the ribosome reads the  nucleotides  of mrna three by three, in units called  codons  , and matches each to three nucleotides on the trna, called the anticodon. finally, during termination, the ribosome unbinds from the mrna, and the  amino acid  chain goes on to be processed and folded to make the final, functional protein