TEAS 7 Biology: Master Key Concepts

ATI TEAS 7

Biology

1. Which of the following is the basic unit of the nervous system?

A. Neuron
B. Nerve
C. Ganglion
D. Neuroglia

Correct answer: A

Rationale: Rationale: Neurons are the basic structural and functional units of the nervous system. They are specialized cells that transmit information through electrical and chemical signals. Nerves are bundles of neurons, ganglia are clusters of nerve cell bodies outside the central nervous system, and neuroglia are support cells for neurons. However, neurons are specifically responsible for transmitting and processing information in the nervous system, making them the basic unit of this system.

2. In an SN2 reaction, the rate of the reaction is affected by

A. Only the concentration of the nucleophile
B. Only the concentration of the electrophile
C. Neither the concentration of the nucleophile nor the electrophile
D. Both the concentration of the nucleophile and the electrophile

Correct answer: D

Rationale: In an SN2 reaction, the rate of the reaction is affected by both the concentration of the nucleophile and the electrophile. This is because in an SN2 reaction, the nucleophile directly attacks the electrophilic center, leading to the formation of the product. A higher concentration of nucleophile increases the chances of successful collisions with the electrophile, thereby increasing the reaction rate. Similarly, a higher concentration of the electrophile provides more reaction sites for the nucleophile to attack, also increasing the rate of the reaction. Therefore, both the nucleophile and electrophile concentrations play crucial roles in determining the rate of an SN2 reaction.

3. Which of the following is a functional group commonly found in alcohols?

A. Carbonyl
B. Hydroxyl
C. Amine
D. Ester

Correct answer: B

Rationale: The hydroxyl functional group (OH) is commonly found in alcohols. The other choices are associated with different functional groups.

4. A temporary loss of consciousness due to insufficient blood flow to the brain is called:

A. Stroke
B. Seizure
C. Syncope (fainting)
D. Coma

Correct answer: C

Rationale: The correct answer is C: "Syncope (fainting)". Syncope is a temporary loss of consciousness caused by insufficient blood flow to the brain. During syncope, there is a brief interruption in the brain's blood supply, leading to a temporary loss of consciousness and muscle tone. This is different from a stroke (A), which is caused by a blockage or rupture of blood vessels in the brain, resulting in permanent damage. Seizures (B) involve abnormal electrical activity in the brain and can cause a variety of symptoms, including loss of consciousness, but they are not specifically due to insufficient blood flow. Coma (D) is a state of prolonged unconsciousness where a person is unresponsive and cannot be awakened. Therefore, the most appropriate term for a temporary loss of consciousness due to insufficient blood flow to the brain is syncope.

5. Where does bile, a substance that helps digest fats, come from?

A. Stomach
B. Pancreas
C. Liver
D. Gallbladder

Correct answer: C

Rationale: Rationale: Bile is a substance that helps digest fats by emulsifying them, which means breaking down large fat globules into smaller droplets to increase the efficiency of fat digestion by enzymes. The liver produces bile, which is then stored and concentrated in the gallbladder before being released into the small intestine to aid in the digestion and absorption of fats. The stomach (option A) is responsible for the initial digestion of food through the action of gastric juices, but bile is not produced in the stomach. The pancreas (option B) secretes digestive enzymes such as lipase to further break down fats in the small intestine, but it does not produce bile. The gallbladder (option D) stores and concentrates bile produced by the liver but does not actually produce bile itself.