1. The measurable electrical activity of the brain is recorded by a:

A. CAT scan
B. MRI scan
C. Electroencephalogram (EEG)
D. X-ray

Correct answer: C

Rationale: The correct answer is C: "Electroencephalogram (EEG)". An EEG is a non-invasive test that measures the electrical activity of the brain by placing electrodes on the scalp. It is specifically designed to record brain wave patterns, making it a valuable tool in diagnosing conditions such as epilepsy, sleep disorders, and brain injuries. A CAT scan (A) and MRI scan (B) are imaging techniques that show the structure of the brain, while an X-ray (D) is not typically used to measure brain electrical activity.

2. What is the name for the mixture of reactants and products present during a chemical reaction?

A. Solution
B. Mixture
C. Reaction mixture
D. Precipitate

Correct answer: C

Rationale: This mixture contains both the starting materials (reactants) and the newly formed substances (products) during the reaction process.

3. What is a group of organisms of the same species living in a particular area called?

A. Community
B. Population
C. Ecosystem
D. Habitat

Correct answer: B

Rationale: Rationale: A) Community refers to all the populations of different species living and interacting in a particular area. Since the question specifies organisms of the same species, community is not the correct answer. B) Population is a group of organisms of the same species living in a particular area. This term specifically refers to individuals of the same species and their interactions within a defined area. C) Ecosystem includes all the living organisms (biotic factors) and non-living components (abiotic factors) in a particular area and their interactions. While populations are part of an ecosystem, the term "ecosystem" is broader and includes multiple populations. D) Habitat refers to the specific environment where an organism lives, including the physical and biological factors. It is the place where a population or individual organism resides, but it does not specifically refer to a group of organisms of the same species.

4. In a neutral atom, the number of electrons:

A. Must be equal to the number of protons.
B. Must be less than the number of protons.
C. Must be greater than the number of neutrons.
D. Can vary depending on the atom's temperature.

Correct answer: A

Rationale: Must be equal to the number of protons - For electrical neutrality, the positive charge of protons must be balanced by the negative charge of an equal number of electrons.

5. Cystitis is an inflammation of the:

A. Kidneys
B. Bladder
C. Ureters
D. Urethra

Correct answer: B

Rationale: The correct answer is B: Bladder. Cystitis is an inflammation of the bladder, typically caused by a bacterial infection. Symptoms include frequent and urgent urination, along with pain or discomfort in the pelvic area. The kidneys (option A) are responsible for filtering blood and producing urine, but they are not the site of inflammation in cystitis. The ureters (option C) are the tubes that connect the kidneys to the bladder and are not typically affected by cystitis. The urethra (option D) is the tube that carries urine from the bladder out of the body, but it is not where the inflammation occurs in cystitis.

6. What is the difference between homologous chromosomes and sister chromatids?

A. Homologous chromosomes have the same genes but may have different alleles, while sister chromatids are identical copies of the same chromosome.
B. Homologous chromosomes are only found in diploid cells, while sister chromatids are found in both haploid and diploid cells.
C. Both homologous chromosomes and sister chromatids are genetically identical, but only sister chromatids separate during mitosis.
D. Both homologous chromosomes and sister chromatids can separate during mitosis, but only homologous chromosomes have different alleles.

Correct answer: A

Rationale: Rationale: - Homologous chromosomes are pairs of chromosomes that have the same genes in the same order, one from each parent. While they carry the same genes, they may have different alleles (variants of a gene). - Sister chromatids are exact copies of each other, formed during DNA replication. They are held together by a centromere and are produced during the S phase of the cell cycle. - During meiosis, homologous chromosomes pair up and exchange genetic material through crossing over, leading to genetic variation. Sister chromatids separate during mitosis to ensure each daughter cell receives an identical copy of the genetic material.