BIOB11H3 Lecture : Biology part 2 lecture notes.docx
Document Summary
Ingestive heterotrophs: multicellular eukaryotes, can reproduce sexually with dominant diploid stage, 2 unique cell types nerve cells/ muscle cells that permit movement, unique gene families called homeobox-containing genes with similar organization and function, have common gene sequences. Multicellular : lack cell walls, have cytoskeleton for internal structure support, held together with. Intercellular junction ( desmosomes, gap junctions, tight junctions ) Ingestive heterotrophs (internal digestion) : they eat others, cannot produce food themselves, digest internally. Reproduce sexually : spend most time in diploid stage, less in haploid stage. 2 unique cell types : nerve cells (impulse conduction, muscle cells (movement) Unique homeobox-containing genes : they have family of genes (homeobox genes, role in regulating development, turns on and off other genes. Animals have common gene sequences (shows relations between other animals) 6 traits of body plans are used to describe animals : symmetry, tissues, body cavities, development patterns, segmentation, external appendages.
