If an intestinal cell in a grashhopper contains 24 chromosomes, a grasshopper sperm cell contains __ chromosomes?
What phase of mitosis is opposite of prophase in terms of nuclear changes?
A biochemist measured the amount of DNA in cells growing in the laboratory and found the amount of DNA doubled between what phases?
G1 and G2 phases of cell cycle
What is not a function of mitosis?
- repair wounds
- production of gametes from diploid cells
- replacement of lost or damaged cells
- multiplication of somatic cells
A fruit fly cell has 8 chromosomes. This means that __ different combinations of chromosomes are possible in its gametes.
Why are individuals with chromosome 21, which causes down syndrome, more numerous than individuals with an extra chromosome 3 or 16?
Extra copies of other chromosomes are probably more fatal
Compare cytokinesis in plant and animal cells
cleavage furrow pinches animal cell in two, in plant cell the vessicles form a cell plate at midline of parent cell. Cell wall fuse with plasma membrane while cell wall grows and seperates 2 daughter cells.
Edward was found to be heterozygous (Ss) for sickle-cell trait. The alleles represented by the letters S and s are:
on homologous chromosomes
Whether an allele is dominant or recessive depends on:
whether it or another allele determines the phenotype when both are present
Mendel studied the inheritance patterns or 2 inheritance patterns of 2 characters at once to find out what?
whether genes for the 2 characters are inherited together or seperately
A geneticist found a particular mutation has no effect on the polypeptide coded by a gene. This mutation probably involved:
- deletion of one nucleotide
- alteration of the start codon
- insertion of one nucleotide
- deletion of the entire gene
- substitution of one nucleotide
which of the following correctly ranks the structures in order of size, from largest to smallest?
The control of gene expression is more complex in multicellular eukaryotes than in prokaryotes because:
eukaryotes have fewer genes, so each gene must do several jobs
Your bone cells, muscle cells, and skin cells look different because:
different genes are active in each kind of cell
All your cells contain proto-oncogens, which can change into cancer-causing genes. Why do cells possess such potential time bombs?
Proto-oncogenes normally control cell division
What would be considered a transgenetic organism?
- a bacterium that has recieved genes via conjugation
- a human given a corrected human blood-clotting gene
- a fern grown in cell culture from a single fern root cell
- a rat with rabbit hemoglobin genes
- a human treated with insulin produced by bacteria