Q: Vertebrate chordates have what part of the skeletal system?
Options:
- (A) spinal column
- (B) hard bones
- (C) aerobic capacity
- (D) cartilage bones
- (E) critical organs
- (F) joints
- (G) fur and fat
- (H) graptolites
A: So, my chain of thought: Vertebrate chordates have a backbone. Invertebrates are animals who lack a backbone or spinal column. Vertebrate chordates have a spinal column. The answer is (A).

Q: What do frogs breathe with when they are adults?
Options:
- (A) skin
- (B) fins
- (C) lungs
- (D) oxygen
- (E) gills
- (F) air
- (G) Energy
- (H) Gases
A: So, my chain of thought: Most amphibians breathe with gills as larvae and with lungs as adults. All frogs are amphibians. Frogs breathe with gills as larvae and with lungs as adults. The answer is (C).

Q: What is a diploid zygote the result of?
Options:
- (A) photosynthesis
- (B) Plant reproduction
- (C) diploid sperm and egg
- (D) mate with females
- (E) Leptospirosis
- (F) haploid sperm and egg
- (G) triploid sperm and egg
- (H) two haploid eggs
A:
So, my chain of thought: Gametes then unite in fertilization and form a diploid zygote. Gametes are haploid egg or sperm that fuse to form a zygote. Diploid zygotes are the result of a haploid sperm and egg combining. The answer is (F).