Which is true about scientific knowledge?
a. it is never reliable.
b. it is open to change.
c. it always becomes a fact.
d. it is rarely proven wrong.

Study the diagram of a desert food chain . what would most likely happen if the kangaroo rats were killed off and removed from the food chain ?

Use this dichotomous key for insect identification to identify the insect shown. 1. a. insect has one pair of wings. order diptera b. insect has two pairs of wings. go to #2 2. a. front wings thicker in texture than hind wings go to #3. b. front and hind wings are same texture throughout. go to #4 3. a. front wings are short order dermaptera b. front wings cover entire abdomen order coleoptera 4. a. wings with scale on all parts of their area. order lepidoptera b. wings without scales go to #5. 5. a. hind wings smaller than front wings. order ephemeroptera b. front and hind wings nearly equal in size. order odonata the insect pictured is in the order diptera. ephemeroptera. coleoptera. odonata.

Refer to the family pedigree shown here. in generation i, one parent is affected by the gene mutation and one parent isn't. in generation ii, all three children are affected by the gene mutation. what can you conclude about this gene mutation? a. all children born in future generations will be affected by this disorder. b. this gene mutation is a dominant disorder. c. this gene mutation is a recessive disorder. d. the generation i mother is a carrier of this gene mutation.