Microbiology - Eukaryotic Structure

The size of a eukaryotic cell ribosome is ______.

80s

The best definition of endosymbiosis is ________.

A pre-eukaryotic cell was infected by a prokaryote, and symbiosis between the two cell types gave rise to the modern-day eukaryotic cell

Long, thin, 7 nm in diameter, concentrated just inside the cytoplasmic membrane

Actin Filament

What groups contain eukaryotic microorganisms?

Bacteria, Protozoa, helminths, and fungi

Choose the statement that correctly describes the major difference between bacterial and eukaryotic ribosomes.

Bacterial and eukaryotic ribosomes differ in size.

T/F : The nuclear envelope is a single layer.

False

T/F :Scientists believe that the modern eukaryotic cell evolved 3.5 billion years ago when a photosynthetic bacteria and an aerobic bacteria fused together.

False - 2.7 Billion years ago

Two different kinds of appendages may be found on eukaryotic cells that enable them to move. ________ are long slender locomotor appendages that are usually single and few in number, whereas ________ are appendages which are numerous and short.

Flagella; cilia

An organelle that is a stack of flattened, membranous sacs and functions to receive, modify, and package proteins for cell secretion is the ________.

Golgi apparatus

Ropelike structures, 10 nm in diameter, provide structural reinforcement

Intermediate Filament

Which of the following is not true of the cytoskeleton?

Made up of cilia

Long, hollow tubes that maintain cell shape and help transport items within the cell

Microtubule

Which organelle contains cristae where enzymes and electron carriers for aerobic respiration are found?

Mitochondria

Which of the following is not a function of the eukaryote glycocalyx?

Movement

Which of the following is found in eukaryotic cells but not in the cells of bacteria?

Nucleus, lysosomes, ER, and mitochondria

Which statement that best describes the role of mitochondria?

Provide cell with energy through cell respiration

Which of the following lines of evidence suggest that mitochondria evolved from the endosymbiosis of a pre-eukaryotic cell with a prokaryote?

They contain circular molecules of DNA, divide independently from the cell, contain 70S ribosomes.

T/F : Eukaryotic mitochondria have their own 70S ribosomes and circular DNA.

True

T/F : Rough endoplasmic reticulum is studded with ribosomes.

True

T/F : The eukaryotic cell membrane is a bilayer of sterols.

True

Mitochondria likely originated from _______.

bacteria

When a eukaryotic cell is not undergoing mitosis, the DNA and its associated proteins appear as a visible network of dark fibers called the _____.

chromatin

Composed of DNA, genetic information of the cell

chromosomes

n eukaryotic cells, ribosomes have two locations: scattered in the ________ and on the surface of the _________.

cytoplasm; endoplasmic reticulum

The cell's series of tunnel-like membranes functioning in transport and storage are the _______.

endoplasmic reticulum

Mitochondria possess all of the following except ________.

enzymes for photosynthesis

The cytoskeleton ________.

helps maintain cell shape, functions in movements of the cytoplasm, provides support, and anchors organelles.

A(n) _______ originates from the Golgi apparatus as one type of vesicle that contains a variety of enzymes for intracellular digestion.

lysosome

The Golgi apparatus ________.

modifies proteins

Double membrane with pores

nuclear envelope

The passageways in the nuclear envelope for movement of substances to and from the nucleus and cytoplasm are called nuclear ________.

nuclear pores

Dense granular mass made of RNA, which is the site of ribosomal RNA synthesis and ribosomal subunit assembly

nucleolus

The site for ribosomal RNA synthesis is the ______.

nucleolus

Histones are ________.

proteins associated with DNA in the nucleus

The eukaryote cell membrane is composed of ______.

sterols, proteins, phospholipids, cholesterol

Eukaryotic cell membranes contain large lipid molecules called sterols, whereas prokaryotic membranes lack sterols. One argument supporting the presence of these sterols in eukaryotes is that ________.

unlike prokaryotes, many eukaryotes lack the protection of a cell wall and therefore require sterols to add some strength and rigidity to the membrane