CYTOGENETICS L2, CELL- PRELIMS

What is the basic functional unit of every living thing

Cell

What are tissues

Similar cells that are grouped together and function to serve a common purpose

What is the first of the four basic tissues

Epithelium

What does epithelium do

Lines the surface and is very thin

What is the second basic tissue type

Connective

What is the third basic tissue type

Muscle

What is the fourth basic tissue type

Nervous

What is an organ

A group of tissues with a common purpose

What is an organ system

Organs working together to perform specific tasks and a collection of associated functions

What are some functions performed by organ systems

Digestion, respiration, reproduction

How many different types of cells is the human body composed of

More than 200

What surrounds every cell

A bi-lipid plasma membrane

What does every cell possess

Functioning organelles

What do cells synthesize

Macromolecules for their own use or for export

What do cells produce

Energy

What are cells capable of

Communicating with other cells

What is protoplasm referred to as

The "unod" of the cell

What is protoplasm

The living substance of the cell

What are the two compartments of protoplasm

Cytoplasm, Karyoplasm

What makes up the bulk of the cytoplasm

Water

What is suspended and/or dissolved in the cytoplasm

Various organic and inorganic chemicals

What is cytosol

Fluid suspension or undissolved portion in the cytoplasm

What does the cytosol contain

Organelles

What is the cytoskeleton referred to as

"Bukog" sa cell

What are the components of the cytoskeleton

Microtubules, Microfilaments

What does the cytoskeleton system maintain

Shape of the cells, ability to move, intracellular pathways within the cell

What shapes can cells take due to the cytoskeleton

Squamous, cuboidal, columnar, pseudostratified, transitional

What are organelles

Metabolically active cellular structures that execute or perform specific and distinctive functions

What do organelles have

Their own membranes

What are inclusions

By-products of metabolism

What do inclusions serve as

Storage forms of various nutrients, inert crystals, pigments

What is the function of membranes

Serves as boundary of the cell

What are membranes made of

Phospholipid bilayer

What do membranes provide

Large surface areas for biochemical reactions essential for maintenance of life

What do membranes do to the cell

Partition the cell into compartments

What compartments are formed by membranes

Nucleus, Organelles

What is another name for the cell membrane

Plasmalemma or plasma membrane

What are the functions of the cell membrane

Maintain structural integrity of the cell, act as interface between the cytoplasm and external environment, regulate cell-cell interactions, recognition of antigens and foreign/altered cells via receptors, controlling movements

What are the components of the protein synthesis and packaging machinery of the cell

Ribosomes, Rough Endoplasmic Reticulum, Golgi Apparatus

When is the Smooth Endoplasmic Reticulum abundant

Only in cells whose active functions are synthesis of steroids, synthesis of cholesterol and triglycerides, detoxification of toxic materials (alcohol and barbiturates)

What do mitochondria possess

Their own DNA

What do mitochondria perform

Oxidative phosphorylation and lipid synthesis

What are the three major components of the cytoskeleton

Filaments, Intermediate filaments, Microtubules

What is the function of thin filaments in the cytoskeleton

Cellular movements

What is the function of intermediate filaments in the cytoskeleton

Maintenance of 3-dimensional framework of the cell

What is the function of microtubules in the cytoskeleton

Act as intracellular pathways

What are centrioles

Small cylindrical structures

What are centrioles composed of

9 microtubule triplets

How are centrioles usually arranged

Paired and perpendicular to each other

Where are centrioles located

In the microtubule organizing center, known as the centrosome

What is the largest organelle of the cell

Nucleus

What is referred to as the "Malacañang" of the cell

Nucleus

What is referred to as the "president" of the cell

DNA

What are the three major components housed in the nucleus

Chromatin, Nucleolus, Nucleoplasm

What is chromatin

The genetic material of the cell

What is the nucleolus

Center for ribosomal RNA (rRNA) synthesis

How can you identify the nucleolus

It is deeply stained (Dark area)

What type of structure is the nucleolus

Non-membrane bound structure

When is the nucleolus observed

Only during interphase (cell's resting phase)

What happens to the nucleolus during cell division

It dissipates

How many nucleoli are typically found in each cell

No more than 2-3

What kind of DNA does the nucleolus contain

Small amount of inactive DNA

What happens to the nucleolus in malignancy

It becomes hypertrophic

Where is the nucleolus located

In the pale-staining fibrillar center

Which chromosomes contain the nucleolar organizing regions (NORs)

13, 14, 15, 21, 22

What is synthesized in the nucleolar organizing regions (NORs)

rRNA

What is the cell cycle

A series of events that prepare the cell for dividing into 2 daughter cells

What are the two major events of the cell cycle

Interphase, Mitosis

What is Interphase

The longer period during which the cell increases in size and replicates its genetic material

What part of the cell cycle occupies most of the cell's "life"

Interphase

What two things happen during Interphase

The cell increases its size and content, and replicates its genetic material

What is Mitosis

A short period during which the cell divides its nucleus and cytoplasm

How long does mitosis usually last

Only 10-20 hours

What happens during the G1 (gap) phase of interphase

Synthesis of macromolecules essential for DNA duplication begins

What is the role of the cell during G1 phase

Performing assigned tasks, metabolizing, synthesizing, etc.

What triggers the cell to begin the cell division event

Replacement of dead or dying cells, growth and development, reproduction

What occurs during the S (synthetic) phase

DNA is duplicated

How does DNA change from G1 to G2 phase

From single-stranded in G1 to double-stranded in G2

What happens during the G2 phase

Preparation for mitosis

What protein is synthesized during G2 phase

Tubulin

Why is tubulin synthesized during G2 phase

To manufacture the microtubules of the spindle apparatus in prophase of mitosis

What happens to cells that become highly differentiated after the last mitotic event

They may cease to undergo mitosis and enter G0 phase

What is the G0 phase

Resting stage / outside or stable phase

Which cells enter the G0 phase permanently

Neurons, muscles

Which cells enter the G0 phase temporarily

Peripheral lymphocytes

When does mitosis occur in the cell cycle

At the conclusion of G2 phase

What does mitosis complete

The cell cycle

What is karyokinesis

Nuclear division

What is cytokinesis

Cytoplasmic division

What happens to chromosomes during prophase

They condense to become visible microscopically

What do chromosomes consist of in prophase

Two parallel sister chromatids joined together at one point (centromere)

What happens to the nucleolus during prophase

It disappears

What happens to the centrosome during prophase

It divides

What does each centrosome contain after division

A pair of centrioles and a microtubule-organizing center (MTOC)

What develops from each MTOC during prophase

Astral rays and spindle fibers

What is the role of astral rays in prophase

Assist in orienting the MTOC at the pole

What is the role of spindle fibers in prophase

Assist in directing the chromosome migration to the pole

What develops at the centromere region of each chromatid

A new MTOC called a kinetochore

To which part of the chromatid does the kinetochore belong

Only to one sister chromatid

What attaches to the kinetochore during prophase

Spindle fibers