lab 4

________ are membranous sacs that detoxify harmful chemicals.

Peroxisomes

You are observing a slide that contains cells undergoing cell division, and you have focused on a cell that has darkly staining X-shaped chromosomes that appear loose throughout the cell. You cannot see a nuclear envelope. This cell is in ________.

prophase

The plasma membrane not only provides a protective boundary for the cell but also determines which substances enter or exit the cell. We call this characteristic __________.

selective permeability

In which phase(s) of mitosis do the chromosomes contain a single copy of DNA?

telophase and anaphase

The nucleus of the cell contains its genes, which are sections of ________.

DNA

________ carry out specific functions inside cells, whereas ________ store glycogen, lipids, pigments, and other substances.

Organelles, inclusions

Plasma cells are key to the immune response because they secrete antibodies. Given that antibodies are made of protein, which membrane-enclosed cell organelle would you expect the plasma cells to have in abundance?

Rough endoplasmic reticulum

This organelle digests other worn-out organelles and foreign substances that have entered the cell.

lysosome

Because these organelles are responsible for providing most of the ATP needed by the cell, they are often referred to as the "powerhouses" of the cell. They are the __________.

mitochondria

Only one human cell has a flagellum. This specialization allows the cell to propel itself forward. It is a ________.

sperm cell

These small bodies are found inside the nucleus of the cell. Made of proteins and RNA, these structures assemble ribosomes. They are ________.

nucleoli

What event immediately precedes anaphase?

Chromosomes cluster at the midline of the cell.

________ is/are a contractile ring of actin microfilaments that eventually results in the division of the cytoplasm.

Cleavage furrow

Some antifungal medications work by blocking DNA synthesis in the fungal cell. During which phase of the cell cycle do these medications work?

S phase

This organelle is particularly important during cell division. It directs the formation of the mitotic spindle.

centriole

Which of the following is not considered to be a cytoskeletal element?

centrioles

When a cell is NOT dividing, the DNA is loosely spread throughout the nucleus in a threadlike form called __________.

chromatin

The nucleus, plasma membrane and ________ are the three major regions of cells that can readily be seen with a light microscope.

cytoplasm

This organelle stores and transports proteins, and synthesizes phospholipids and cholesterol.

endoplasmic reticulum

The end product of mitosis is four genetically identical daughter nuclei.

false

Name the rod-shaped organelles that have a double-membrane wall and that oxidize foodstuffs to make ATP.

mitochondria

The division of human cells consists of a series of events, collectively called ________, or nuclear division, and ________, or division of the cytoplasm.

mitosis, cytokinesis

________ molecules form the major component of the plasma membrane and are arranged in the form of a bilayer.

phospholipid

During this phase of mitosis, the mitotic spindle forms and the nuclear envelope fragments.

prophase

The small size and biconcave shape of this cell gives it flexibility and allows its easy passage through small channels. It is a ________.

red blood cell

The end product of cell division by mitosis is ________.

2 genetically identical daughter cells

During __________ the cell grows and performs its usual activities.

Interphase

Which organelle would you expect to play the largest role in decomposition of the human body?

Lysosomes

During ________, the shortest phase of mitosis, chromosomes are pulled toward the poles of the cell.

anaphase

Ribosomes/ribosomal subunits are found ________.

free in the cytoplasm

This membranous organelle resembles a stack of flattened sacs with bulbous ends and associated vesicles.

golgi apparatus

DNA replication occurs during __________.

interphase

From the time it is formed until it reproduces, the cell undergoes growth and carries out its functions in the body. What is the name for this portion of the cell's life cycle?

interphase

________ are tiny finger like projections on some cell surfaces that increase the surface area for absorption of materials.

microvilli

The plasma membrane allows nutrients to enter the cell and keeps undesirable substances out of the cell. It also allows wastes to pass out of the cell and keeps valuable cell proteins inside the cell. This property is called ________.

selective permeability