Biology › Cell Structures and Organelles
Which organelle is most important for a person who has consumed too much alcohol?
Smooth endoplasmic reticulum
Rough endoplasmic reticulum
Mitochondria
Ribosomes
The question states that the person has consumed too much alcohol, which means that the body must detoxify the chemicals from alcohol. You are therefore looking for the organelle that participates in detoxification of chemicals. In addition to synthesizing lipids, the smooth endoplasmic reticulum plays an important role in detoxification of chemicals. This detoxification process occurs in the liver, which contains an abundance of smooth endoplasmic reticulum.
Rough endoplasmic reticulum and ribosomes are involved in protein synthesis, and mitochondria are the site of energy (ATP) production.
Which of the following is not characteristic found within a fully functional ribosome?
Sugar-phosphate backbone
RNA
Amino acids
N and C terminus
Peptidyl site
A sugar phosphate backbone is characteristic of a DNA sequence. While fully functional ribosomes are composed of a mix of functional RNA and protein the sugar-phosphate components within the RNA do not comprise the backbone of the entire ribosome. This question also requires the knowledge that an amino acid chain has an N and C terminus. Last, it is important to note that the Peptidyl site is where the bond between two amino acids is synthesized.
Many people consume alcohol and drugs on a daily occasion. The body needs a detoxification system against these toxins to prevent harmful accumulation of metabolites from the breakdown of these toxins. What organelle is responsible for this detoxification?
Smooth endoplasmic reticulum
Rough endoplasmic reticulum
Golgi apparatus
Nucleus
Smooth endoplasmic reticulum is primarily responsible for the production of lipids and for the detoxification of drugs and toxins from the body.
Many people consume alcohol and drugs on a daily occasion. The body needs a detoxification system against these toxins to prevent harmful accumulation of metabolites from the breakdown of these toxins. What organelle is responsible for this detoxification?
Smooth endoplasmic reticulum
Rough endoplasmic reticulum
Golgi apparatus
Nucleus
Smooth endoplasmic reticulum is primarily responsible for the production of lipids and for the detoxification of drugs and toxins from the body.
Steroids are an important component of cell membranes and gonadal hormones. What organelle is most important in the synthesis of steroids?
Smooth endoplasmic reticulum
Rough endoplasmic reticulum
Golgi apparatus
Lysosomes
Steroids are a type of lipid that include cholesterol (needed for cell membranes) and gonadal hormones (estrogen, testosterone, and progesterone). Since they are lipids, steroids are synthesized in the smooth endoplasmic reticulum, the site of lipid synthesis.
Remember that smooth endoplasmic reticulum also plays a role in detoxification of harmful chemicals.
Rough endoplasmic reticulum is used to produce proteins that will be secreted from the cell, including most peptide hormones. The Golgi apparatus is used to modify these proteins and create vesicles for protein transport. Lysosomes contain hydrolytic enzymes that digest cellular wastes.
Which of the following is not characteristic found within a fully functional ribosome?
Sugar-phosphate backbone
RNA
Amino acids
N and C terminus
Peptidyl site
A sugar phosphate backbone is characteristic of a DNA sequence. While fully functional ribosomes are composed of a mix of functional RNA and protein the sugar-phosphate components within the RNA do not comprise the backbone of the entire ribosome. This question also requires the knowledge that an amino acid chain has an N and C terminus. Last, it is important to note that the Peptidyl site is where the bond between two amino acids is synthesized.
What is the large and spherical organelle in eukaryotic cells that houses genetic information?
Nucleus
Lysosome
Peroxisome
Mitochondrion
The nucleus of a cell contains the genetic information and is the organelle most easily seen when viewing cells under a light microscope. The nucleus is usually spherical and is generally the largest organelle in eukaryotic cells. The mitochondrion is a smaller organelle, and is responsible for making the energy (ATP) in the cell. Lysosomes are small organelles that contain hydrolytic enzymes used to degrade and recycle macromolecules. The peroxisome is an organelle responsible for catabolism of lipids, detoxification of certain compounds, and regulation of cellular metabolism.
Which of the following organelles is commonly referred to as the powerhouse of the cell?
Mitochondria
Golgi apparatus
Rough endoplasmic reticulum
Lysosome
Nucleus
The mitochondria are responsible for synthesis of the majority of the cell's ATP. This is why mitochondria are commonly referred to as the powerhouse of the cell. The rough endoplasmic reticulum and Golgi apparatus are involved in protein synthesis and delivery. The nucleus houses the DNA and is the site of transcription and ribosome assembly (nucleolus). The lysosome contains hydrolytic enzymes that are used for degradation of certain materials.
Which of the following organelles is found in plant cells, but not in animal cells?
Chloroplasts
Mitochondria
Ribosomes
Nucleus
Plant cells are very similar to animal cells, but receive energy from sunlight. As a result, they require chloroplasts in order to house the chlorophyll where photosynthesis takes place. Animal cells are incapable of photosynthesis, and do not contain chloroplasts.
The other listed structures are found in both animal and plant cells.
Which of the following organelles is present in plant cells, but not in animal cells?
Chloroplasts
Mitochondria
Cell membrane
Nucleus
Rough endoplasmic reticulum
Mitochondria are membrane-bound organelles found in both plant and animal cells, and provide energy for the cell by converting different forms of reactants into ATP. The cell membrane is present in both types of cells and separates the environment from the inside of the cell, and provides cell structure and protection. The rough endoplasmic reticulum is present in both types of cells and is responsible for the storage and packaging of proteins and vesicles. The nucleus is present in both types of cells and controls the general activities of the cell, including gene expression and cell division.
Of these answer choices, only chloroplasts are present in plants cells, but not animal cells. Plant cells are photosynthetic and create their own form of energy from sunlight. The photosynthesis occurs in the chloroplasts of plant cells, which contain the pigment chlorophyll.