TEAS 7 Biology: Master Key Concepts

ATI TEAS 7

Biology

1. Homologous structures are those that:

A. Have the same function but different origins
B. Have different functions but the same origin
C. Are similar in appearance and function due to shared ancestry
D. Are identical in both appearance and function

Correct answer: C

Rationale: Rationale: - Option A is incorrect because structures with the same function but different origins are analogous structures, not homologous structures. - Option B is incorrect because structures with different functions but the same origin are also not homologous structures; they are considered to be vestigial structures. - Option D is incorrect because structures that are identical in both appearance and function are not necessarily homologous; they could be the result of convergent evolution. Homologous structures are those that share similarities in appearance and function due to being inherited from a common ancestor. These structures may have undergone modifications over time to adapt to different functions in different species, but their fundamental similarities can be traced back to a shared evolutionary history.

2. Which type of reaction is represented by the equation A + B â†’ AB?

A. Synthesis
B. Decomposition
C. Single Replacement
D. Double Replacement

Correct answer: a

Rationale: Synthesis reactions involve the combination of two or more substances to form a new compound.

3. Which of the following is NOT a primary producer in an ecosystem?

A. Grass
B. Deer
C. Algae
D. Mushroom

Correct answer: B

Rationale: Rationale: - A) Grass: Grass is a primary producer because it can photosynthesize and convert sunlight into energy, making it the base of the food chain. - B) Deer: Deer are consumers that feed on primary producers like grass, so they are not primary producers themselves. - C) Algae: Algae are primary producers that can photosynthesize and produce energy from sunlight. - D) Mushroom: Mushrooms are decomposers that break down organic matter, so they are not primary producers.

4. Bradycardia refers to a heart rate that is:

A. Normal (60-100 bpm)
B. Slightly elevated (100-120 bpm)
C. Significantly elevated (>120 bpm)
D. Abnormally slow (<60 bpm)

Correct answer: D

Rationale: The correct answer is D. Bradycardia refers to an abnormally slow heart rate, typically defined as being less than 60 beats per minute (bpm). A heart rate of 60-100 bpm is considered normal, not bradycardia. Choices B and C incorrectly describe elevated heart rates, which are not characteristic of bradycardia. Therefore, option D is the most accurate description of bradycardia as it signifies a heart rate that is slower than normal.

5. What is the term for a genetic disorder caused by a mutation on the X chromosome?

A. Autosomal dominant disorder
B. Autosomal recessive disorder
C. Sex-linked recessive disorder
D. Sex-linked dominant disorder

Correct answer: C

Rationale: Rationale: - Autosomal dominant disorders (Option A) are caused by a mutation in one copy of a gene on one of the non-sex chromosomes (autosomes). These disorders do not specifically involve the X chromosome. - Autosomal recessive disorders (Option B) are caused by mutations in both copies of a gene on the autosomes. They are not directly related to mutations on the X chromosome. - Sex-linked dominant disorders (Option D) are rare and typically result in more severe symptoms in males because they only need one copy of the mutated gene on the X chromosome to express the disorder. This is not the term for a genetic disorder caused by a mutation on the X chromosome. - Sex-linked recessive disorders (Option C) are genetic disorders caused by mutations on the X chromosome. These disorders are more commonly seen in males because they have only one X chromosome, making them more susceptible to X-linked mutations. Females have two