which organelle is responsible for the final stages of protein modification and packaging for secretion in animal cells

ATI TEAS 7

TEAS Test 7 science quizlet

1. Which organelle is responsible for the final stages of protein modification and packaging for secretion in animal cells?

A. Rough endoplasmic reticulum (RER)
B. Smooth endoplasmic reticulum (SER)
C. Ribosomes
D. Golgi apparatus

Correct answer: D

Rationale: The Golgi apparatus is responsible for the final stages of protein modification and packaging for secretion in animal cells. After proteins are synthesized in the rough endoplasmic reticulum (RER), they are transported to the Golgi apparatus for further processing, sorting, and packaging before being sent to their final destination within or outside the cell. The smooth endoplasmic reticulum (SER) is mainly involved in lipid metabolism and detoxification processes, not protein modification. Ribosomes are the cellular organelles responsible for protein synthesis, not the final stages of protein modification and packaging for secretion, which is the role of the Golgi apparatus.

2. Which technology allows scientists to directly edit the human genome?

A. Polymerase Chain Reaction (PCR)
B. Gel electrophoresis
C. DNA sequencing
D. CRISPR-Cas9

Correct answer: D

Rationale: CRISPR-Cas9 is the correct answer. A) Polymerase Chain Reaction (PCR) is used for amplifying specific DNA segments, not directly editing the human genome. B) Gel electrophoresis is for separating DNA fragments by size, not for genome editing. C) DNA sequencing determines DNA nucleotide order but does not directly edit the genome. D) CRISPR-Cas9 technology enables precise modifications in the DNA of organisms, including humans. It guides the Cas9 enzyme to specific genome locations for targeted edits, revolutionizing genetic research and offering various applications in gene editing and therapy. Unlike the other techniques mentioned, CRISPR-Cas9 is specifically designed to make changes in the genetic code itself, making it a powerful tool for genetic manipulation.

3. What is a characteristic feature of a convex lens?

A. Converge light rays
B. Diverge light rays
C. Focus sound waves
D. Create virtual images only

Correct answer: A

Rationale: A convex lens is characterized by its ability to converge light rays. The convex lens is thicker in the middle and thinner at the edges, causing light rays passing through it to converge or come together at a focal point on the opposite side of the lens. This convergence of light rays is what distinguishes convex lenses. Choice B is incorrect as convex lenses do not diverge light rays. Choice C is incorrect as convex lenses do not focus sound waves but rather light waves. Choice D is incorrect as convex lenses can create both real and virtual images, not just virtual images.

4. What is the involuntary process of emptying the bladder called?

A. Filtration
B. Micturition
C. Reabsorption
D. Excretion

Correct answer: B

Rationale: Micturition, also known as urination or voiding, is the involuntary process of emptying the bladder. During micturition, the bladder muscle contracts, and the sphincter muscles relax, allowing urine to be expelled from the body. Filtration is the process of separating solids from liquids in the body, not related to emptying the bladder. Reabsorption involves absorbing substances back into the bloodstream, not related to emptying the bladder. Excretion is the process of eliminating waste products from the body, not specifically the process of emptying the bladder.

5. What is the role of RNA in the regulation of gene expression?

A. Provides energy for the process
B. Controls the timing and location of protein synthesis
C. Translates the genetic code into amino acids
D. Stores genetic information

Correct answer: B

Rationale: A) RNA does not provide energy for the process of gene expression. Energy is typically provided by molecules like ATP. B) RNA plays a crucial role in controlling the timing and location of protein synthesis through processes like transcriptional regulation, RNA splicing, and post-transcriptional modifications. It helps determine when and where specific proteins are produced in the cell. C) While mRNA translates the genetic code into amino acids during the process of translation, this is not the primary role of RNA in the regulation of gene expression. D) RNA does not store genetic information in the same way that DNA does. DNA is the molecule responsible for storing genetic information in the form of genes. Therefore, option B is the most appropriate choice as it accurately describes the role of RNA in regulating gene expression.