Cytology/histology Flashcards
A collection of similarly specialized cells that are adapted to perform a specific function
Tissue
The study of cells
Cytology
The study of tissues
Histology
Two or more tissue types combined together to perform a specific function
An organ
A group of organs that work together form?
A system
The basic unit from which all tissues are constructed
A cell
Activities of the cell are those activities that we associate with living:
Ingestion, digestion and utilization of nutrients
Excretion of the residues of the digestive process
Respiration movement
Response to stimuli
Reproduction
A complex structure, which regulates what goes into and out of the cell in a highly specialized way
The cell membrane
The ________________________ surrounds the protoplasm. It keeps the cell separate from other cells, maintains the internal structure of the cell, and separates the cell from its external environment.
Cell membrane
There are also ‘_________’ in the cell membrane that only allow substances of a specific size through, and there are active mechanisms whereby substances are attached to ‘carriers! In order to gain access to the cell
Pore
Cell membranes that allow everything to pass through are called
Permeable membranes
Cell membranes that only allow certain substances to pass through
Semi-permeable membranes
Function of the cell membrane
Transportation of nutrients and oxygen into cell
Transportation of waste products and carbon dioxide out of cells
Transportation of products manufactured by the cell, out of cell
Detection of foreign substances
Protection against foreign invaders
Interaction with other substances via a system of markers and receptors
Maintaining balanced internal environment
Keeping cell as individual entity, separate from adjacent cells
Name the four methods by which substances cross the cell membrane
Diffusion
Osmosis
Facilitated diffusion
Active transport
This is the process where a dissolved substance moved from an area of high concentration of that substance to an area of low concentration. It can take place across the cell membrane via minute pores, provided the molecules of the substance are small enough
Diffusion
This is a process where the water molecules move from an area of low substance concentration (little substance, lot of water) to an area of high substance concentration (lot of substance, little water) to even out the substance concentration. This takes place across a semi-permeable or selectively permeable membrane, which does not permit the substance to pass through
Osmosis
This is when some substances, which are lipid soluble, pass into the cell by dissolving in the lipid component in the cell membrane
Facilitated diffusion
This involves the movement of substances into or out of the cell, by being bound to a carrier substance, which actively crosses the membrane
Active transport
This is an opaque, colorless gel-like liquid composed of water and various dissolved or suspended substances
Protoplasm
The protoplasm is divided into two regions – that within the nucleus, called ______________, and that outside of the nucleus, called ________________.
Nucleoplasm , cytoplasm
Within the protoplasm of the cell the dissolved or suspended components are organized into __________________, which are the working components of the cell, each with specific cellular functions.
Organelles
Name the 9 commonly occurring organelles
Nucleus Ribosome Mitochondria Golgi complex Vacuoles Lysosomes Centrosomes Centrioles Endoplasmic reticulum
The controlling body of the cell.
The nucleus
These are the site of protein synthesis using amino acid as directed by RNA messengers. (‘Protein factories’)
Ribosomes
These are the sites of energy generation for the cell using oxygen and nutrients. (‘Power houses’)
Mitochondria
These are small sacs, which collect secretory products for use or disposal. (‘Waste disposal units’)
Golgi complexes ( or golgi apparatus)
These are sac like structures, which can merge with each other or the cell membrane, and aid in transport of substances into and out of the cell. (‘Transport department ‘)
Vacuoles
These contain enzymes for digestion, usually foreign substances
Lysosomes
This is a structure lying near the nucleus, which becomes important in cell division. It contains centrioles
Centrosome
These are bundles of microtubules, which form a spindle structure during cell division
Centrioles
These are membrane-lined tubules to which ribosomes may be attached. May be rough or smooth
Endoplasmic reticulum
This is a specialized molecule, which forms the building blocks of all the genetic material in the body. It is found in the nucleus of every cell.
DNA deoxyribonucleic acid
What is DNA made up of?
An arrangement of four essential amino acids arranged in two long strands forming a helix–double-stranded helix.
A structure that looks like a spiraling stepladder
A helix
Segments of DNA form?
Genes