ATI TEAS 7
ATI TEAS 7 science review
1. What does half-life refer to?
- A. Radioactive intensity to completely disappear
- B. The number of neutrons in a nucleus to double
- C. The number of protons in a nucleus to change
- D. An isotope to decay by half of its initial quantity
Correct answer: D
Rationale: Half-life refers to the time it takes for half of the radioactive atoms in a sample to decay. This means that after one half-life, half of the initial quantity of the radioactive substance will have decayed. Choice A is incorrect because radioactive intensity doesn't completely disappear during half-life. Choice B is incorrect as half-life doesn't refer to the number of neutrons doubling. Choice C is incorrect as half-life doesn't relate to the number of protons changing.
2. What role does DNA play in evolution?
- A. It stores genetic information that can be passed on to offspring.
- B. It allows for mutations that can introduce new variations.
- C. It regulates the expression of genes that influence traits.
- D. All of the above
Correct answer: D
Rationale: A) DNA stores genetic information that is passed on from parents to offspring through the process of reproduction. This genetic information contains instructions for the development and functioning of an organism. It serves as the hereditary material that carries the blueprint for an organism's traits and characteristics, allowing for the transmission of genetic information from one generation to the next. B) DNA can undergo mutations, which are changes in the genetic sequence. These mutations can introduce new variations in the DNA, leading to genetic diversity within a population. These variations are essential for natural selection and adaptation to changing environments. C) DNA plays a crucial role in regulating the expression of genes. Gene expression determines which proteins are produced in an organism, influencing its traits and characteristics. By controlling gene expression, DNA contributes to the development and maintenance of an organism's traits. D) Therefore, DNA is involved in all of the above processes, making it a key factor in evolution by driving genetic variation, inheritance, and gene expression. The interplay of these functions allows for the diversity and adaptation of species over time, shaping the evolutionary process.
3. Which type of cartilage allows for smooth movement at joints and absorbs shock?
- A. Hyaline cartilage
- B. Fibrocartilage
- C. Elastic cartilage
- D. None of the above
Correct answer: B
Rationale: Fibrocartilage is the correct answer. It is found in areas requiring both support and resilience, such as the intervertebral discs and knee joints. Fibrocartilage contains collagen fibers for strength and proteoglycans for resilience, making it suitable for functions that involve smooth movement at joints and shock absorption. Hyaline cartilage, while providing structural support, is not primarily responsible for smooth movement and shock absorption. Elastic cartilage is more flexible and is found in locations like the ear and epiglottis, but it is not known for its shock-absorbing properties. Choosing 'None of the above' disregards the correct option of fibrocartilage, which is specifically designed for the functions described in the question.
4. What is the role of RNA interference in silencing genes?
- A. Increases protein production
- B. Promotes gene mutation
- C. Inhibits the expression of specific genes
- D. Repairs damaged DNA
Correct answer: C
Rationale: RNA interference (RNAi) is a biological process that involves the silencing of gene expression by inhibiting the translation of mRNA or by degrading mRNA molecules. This mechanism plays a crucial role in regulating gene expression and can be used to selectively silence specific genes. By interfering with the expression of specific genes, RNAi can downregulate protein production from those genes. Therefore, option C, 'Inhibits the expression of specific genes,' is the correct role of RNA interference in silencing genes. Options A, B, and D are incorrect because RNA interference does not increase protein production, promote gene mutation, or repair damaged DNA; its primary function is to inhibit gene expression by degrading or interfering with mRNA.
5. How are kidney stones formed?
- A. Due to excess water not being reabsorbed
- B. When minerals crystallize in the urine
- C. When electrolytes become too concentrated
- D. All of the above
Correct answer: B
Rationale: Kidney stones are formed when minerals in the urine crystallize and stick together to form solid masses. Excess water not being reabsorbed (option A) does not directly contribute to kidney stone formation. Similarly, electrolytes becoming too concentrated (option C) is not a direct cause of kidney stone formation. The correct answer is B because the crystallization of minerals in the urine leads to the formation of kidney stones.
Similar Questions
Access More Features
ATI TEAS Premium Plus
$150/ 90 days
- Actual ATI TEAS 7 Questions
- 3,000 questions with answers
- 90 days access
ATI TEAS Basic
$99/ 30 days
- 3,000 Questions with answers
- 30 days access