Cell Structure and Function Lecture

Seventy question-and-answer style flashcards covering cell structure, organelles, and prokaryotic vs. eukaryotic differences.

What is considered the basic unit of life?

The cell.

Name the three major parts common to most cells.

The cell membrane (plasma membrane), the cytoplasm, and the nucleus.

Which cell structure is semi-permeable and surrounds the cell?

The cell (plasma) membrane.

What is the main structural component of the cell membrane?

A phospholipid bilayer.

What are the hydrophilic portions of a phospholipid called?

The polar heads.

What are the hydrophobic portions of a phospholipid called?

The non-polar tails.

Besides phospholipids, what lipid that modulates membrane fluidity is found in the cell membrane?

Cholesterol.

What type of molecules are embedded in the phospholipid bilayer to assist transport and communication?

Proteins.

What term describes the ability of the cell membrane to allow some substances to pass while blocking others?

Semipermeability.

What rigid outer boundary found only in plants provides protection and prevents drying?

The cell wall.

What polysaccharide primarily makes up the plant cell wall?

Cellulose.

What is the largest area within the cell that contains organelles suspended in cytosol?

The cytoplasm.

What is the semifluid component of cytoplasm called?

Cytosol.

What name is given to membrane-bound specialized subunits inside cells?

Organelles.

Which organelle is known as the “powerhouse of the cell”?

The mitochondrion.

From which parent are mitochondria inherited?

The mother.

What energy-producing process occurs in mitochondria?

Cellular respiration (ATP production).

Which organelle contains digestive enzymes that break down substances and worn-out organelles?

Lysosomes.

What nickname is often given to lysosomes because they can cause self-digestion?

The suicidal sacs.

Which organelle has ribosomes attached and is the site of protein synthesis?

Rough endoplasmic reticulum.

Which type of endoplasmic reticulum lacks ribosomes and synthesizes lipids and steroids?

Smooth endoplasmic reticulum.

What detoxifying organelle is abundant in liver and kidney cells?

Peroxisomes.

What enzyme released by peroxisomes converts toxic hydrogen peroxide to water?

Catalase.

What organelle stores water, wastes, and other materials?

The vacuole.

How does the size of vacuoles in plant cells compare to those in animal cells?

Plant cells have one large central vacuole; animal cells have small vacuoles.

Which organelle stores chlorophyll and carries out photosynthesis?

Chloroplasts.

What green pigment necessary for photosynthesis is housed in chloroplasts?

Chlorophyll.

Which tiny organelles translate genetic information into amino acid chains?

Ribosomes.

What three structural elements compose the cytoskeleton?

Microfilaments, intermediate filaments, and microtubules.

Name one primary function of the cytoskeleton.

Providing structural support and facilitating cell movement.

Which organelle processes, packages, and exports proteins from the cell?

The Golgi apparatus.

What postal-related nickname is given to the Golgi apparatus?

The packaging center or post office of the cell.

What carbohydrate-rich layer on animal cell membranes aids in cell recognition and adhesion?

The glycocalyx.

In which type of cell (plant or animal) are centrioles typically found?

Animal cells.

Where inside the cell are centrioles located?

In the centrosome near the nucleus.

Which organelle serves as the control center of the cell?

The nucleus.

What semifluid substance fills the nucleus?

Nucleoplasm.

What double-membrane structure surrounds the nucleus and has pores?

The nuclear envelope (nuclear membrane).

What nuclear structure is the site of ribosome subunit preassembly?

The nucleolus.

What term refers to the combined DNA and protein material that makes up chromosomes when not condensed?

Chromatin.

What long, whip-like projections propel certain cells?

Flagella.

What short, hair-like projections move materials across cell surfaces?

Cilia.

List three organelles present in both plant and animal cells.

Nucleus, mitochondria, and endoplasmic reticulum (among others).

Name three structures present in plant cells but absent in animal cells.

Cell wall, large central vacuole, and chloroplasts.

Name two structures present in animal cells but usually absent in plant cells.

Centrioles and lysosomes.

Which storage carbohydrate is typical in animal cells?

Glycogen.

Which storage carbohydrate is common in plant cells?

Starch.

Cells without a true nucleus are called what?

Prokaryotic cells.

What molecule forms the bacterial cell wall and provides rigidity?

Peptidoglycan.

What size ribosomes are characteristic of prokaryotes?

70S ribosomes.

What type of reproduction is typical of prokaryotes?

Asexual reproduction by binary fission.

Into which kingdom are prokaryotes such as bacteria classified?

Kingdom Monera.

Cells with a true nucleus and membrane-bound organelles are called what?

Eukaryotic cells.

What size ribosomes are characteristic of eukaryotes?

80S ribosomes.

What two basic reproductive methods are seen in eukaryotes?

Asexual reproduction by mitosis and sexual reproduction via gamete fusion.

Name three kingdoms composed of eukaryotic organisms.

Animalia, Plantae, and Fungi.

Of cellulose, chitin, and peptidoglycan, which is found in fungal cell walls?

Chitin.

What region in a prokaryotic cell contains its single circular DNA strand?

The nucleoid.

Which two energy-converting organelles are absent from prokaryotes but present in eukaryotes?

Mitochondria and chloroplasts.

What property allows the cell membrane to regulate the internal environment of the cell?

Selective permeability.

Which component of the cell membrane often functions as receptors for signal transduction?

Membrane proteins (glycoproteins).

What name is given to the movement of proteins and lipids within the plane of the membrane that cholesterol helps maintain?

Membrane fluidity.

What term describes long chains of amino acids assembled by ribosomes?

Polypeptides (proteins).

Arrange the following levels of biological organization from simplest to most complex: cells, organs, tissues, organ systems, organisms.

Cells → tissues → organs → organ systems → organisms.

Which organ system is responsible for body movement through muscle contraction?

The muscular system.

Which organelle exports proteins in vesicles that fuse with the plasma membrane?

The Golgi apparatus.

Which organelle’s primary job is to remove harmful compounds by oxidation reactions?

Peroxisomes.

What type of cell movement involves a sperm cell swimming using its flagellum?

Locomotion via flagellar propulsion.

What familiar nickname refers to mitochondria because they generate ATP?

The powerhouse of the cell.

What stacks of flattened membrane sacs comprise the Golgi apparatus?

Cisternae.