Flashcards in Cytology/histology Deck (88):
A collection of similarly specialized cells that are adapted to perform a specific function
The study of cells
The study of tissues
Two or more tissue types combined together to perform a specific function
A group of organs that work together form?
The basic unit from which all tissues are constructed
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
Response to stimuli
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.
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
Cell membranes that allow everything to pass through are called
Cell membranes that only allow certain substances to pass through
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
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
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
This is when some substances, which are lipid soluble, pass into the cell by dissolving in the lipid component in the cell membrane
This involves the movement of substances into or out of the cell, by being bound to a carrier substance, which actively crosses the membrane
This is an opaque, colorless gel-like liquid composed of water and various dissolved or suspended substances
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.
Name the 9 commonly occurring organelles
The controlling body of the cell.
These are the site of protein synthesis using amino acid as directed by RNA messengers. ('Protein factories')
These are the sites of energy generation for the cell using oxygen and nutrients. ('Power houses')
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 ')
These contain enzymes for digestion, usually foreign substances
This is a structure lying near the nucleus, which becomes important in cell division. It contains centrioles
These are bundles of microtubules, which form a spindle structure during cell division
These are membrane-lined tubules to which ribosomes may be attached. May be rough or smooth
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
Segments of DNA form?
A number of genes are located together in a specific structure called?
The function of __________ is to process the information that the DNA provides
RNA ribonucleic acid
How many pairs of chromosomes do humans have?
Most of the changes that occur during this process involve the nucleus and the reproduction of the chromosomes, so each daughter cells will have identical genetics to the parent cell. This process of chromosome duplication is called?
The five classic phases of mitosis
The cell is not dividing but DNA in the chromatin is duplicating in preparation
The centrosome divided and a spindle forms. Chromatin thickens to become visible chromosomes, which duplicate
The nuclear membrane disappears. The chromosomes attach to the center of the spindle--half the duplicated strands on one side, and half on the other--joined by a centromere between them
The centromere duplicates and separates. Each half centromere plus attached single chromosome strand migrated to the poles of cell, attached to the spindle. The spindle breaks.
The nuclear membranes reform around each group of chromosomal material, thus creating two nuclei. The cell membranes constricts forming two daughter cells.
The process of producing sex cells that contain only half the genetic material that is found in the body cells
What are the four basic types of tissue
This is a collection of cells whose structure is adapted for the function of forming body linings.
This type of epithelial tissue is made up of a single layer of cells that fit snugly together like the flat stones of a pavement.
This epithelial tissue is made up of a single layer of cube shaped cells that fit closely together. They are seen lying on a basement membrane. They are generally secretory cells, and make up glands throughout the body
This epithelial tissue is made up of a single layer of cylinder shaped cells, with elongated nuclei. They generally line the gastrointestinal tract. Their main functions are secretion and absorption
This epithelial tissue is made up of a single layer of columnar cells with hair like processes in their free edges, called cilia. The function of cilia is movement. The beating of the cilia propels the contents of the tube along the tube.
This epithelial tissue contains multiple layers of epithelial cells of different shapes.
This epithelial tissue contains multiple layers of cells that are pear-shaped.
This is the formation in a gland of any substance for further use such as hormones, sebum, and so on.
This is the formation of a substance to expel waste products
There are two major subdivisions of glands
These glands arise as putpickets from the epithelium, and retain their duct connection to the surface. Examples include sweat glands and sebaceous glands.
These glands arise in the same way, but lose their connection to the surface during development. They become associated with blood vessels, and pour their secretions directly into the blood vessels. Examples include thyroid glands and pituitary glands.
This secretion is of sticky, viscous type of sweat associated with a hair follicle. It occurs in the inguinal, axillary and areolar areas.
This secretion produces sweat of a thin liquid consistency. The occur all over the body.
This secretion involves the destruction of the producing glands. The secretion contains breakdown products of the secreting cells as occurs in the production of sebum
This tissues function is to connect, bind and support body structures.
There are three components of all connective tissue:
This is composed primarily of water. It occurs in different proportions in all connective tissue
Matrix, or ground substance
These vary in structure and function and include many specialized cells such as fibroblasts , macrophages, fat cells, histiocytes, plasma cells and mast cells.
The cells of connective tissue
These differ according to their function. There are three types: collagen, elastin, and reticulin.
This is a fiver produced by the fibroblasts. It is very strong and gives tensile (tension) strength to the connective tissue
This is a finer fibre, which is smaller and weaker than collagen. It forms supportive networks around cell groups.
This is the main elastic component in connective tissue. It is a protein substance, which forms fibres that have great elasticity
These are cells that secrete a substance that becomes collagen, and also so contribute to the ground substance (matrix)
These are leucocytes also called white blood cells, that occur in the tissues outside of the blood vessels. They are capable of independent movement and they surround and absorb foreign material to protect the body again invasion. They also remove debris
These cells contain granules, which secrete histamine, a substance involved in allergic reactions. They also secrete heparin, which is one of the anti-coagulants.
These are large, reticulo-endothelial cells, which function to ingest and remove cell debris and bacteria. They form reticulin fibres, so are also called reticulin cells
These cells are also called adipocytes. They store lipids. They are round cells with the nucleus squashed to one side by the lipids.
These cells secrete antibodies in response to infection
This is a powerful anticoagulant that stops blood from clotting
This is a substance released in an allergic reaction that affects smooth muscles and cell wall permeability, leading to drop in blood pressure, wheezing, and oedema, etc.
What is the most generalized of all connective tissue; it has a semi-solid matrix with widely dispersed cells and white fibres (collagen) and yellow elastic fibres. It is found in almost every part of the body, connecting and supporting organs. Examples include hypodermics of the skin; deep to epithelial tissue of mucus membranes and hollow organs.
Areolar connective tissue
This connective tissue has mainly fat cells, supported by collagen and reticulin fibres. It is closely associated with blood and lymph capillaries. It is a source of fuel, insulation, padding and stores fat-soluble vitamins. It occurs mainly in the breast, buttock, abdominal wall, and thigh. It is also found around the kidney and the eye.
Adipose connective tissue
This tissue is capable of considerable extension and recoil. It consists of few cells, little matrix and masses of yellow elastic fibres. It is found in organs where alteration of shapes it required. Examples include arteries, trachea, bronchi, and lungs.
Yellow elastic tissue
This is strong connective tissue made mainly of closely packed bundles of white fibres, with very little matrix, and few cells. It forms: ligaments which bind bones together; the periosteum of bone; the protective covering of organs such as kidney, blood vessels, brain; muscle sheaths called fascia
White fibrous tissue
This is also known as lymphoid tissue. It has a semi-solid matrix, with fine, branching reticulin fibres. The specialized cells are called lymphocytes, one of the white blood cells. Lymphoid tissue is found in lymph nodes, spleen, tonsils, adenoids, appendix and forming some lymph glands of the small intestines
This is a supportive connective tissue; it consists of a solid but flexible matrix, in which very fine fibres are embedded.
Three types of cartilage.
Appears as smooth blue-white tissue it is found covering the articular surfaces of bones involved in forming synovial joints. It also forms the nasal septum, supports the larynx and lower respiratory tract
Is dense fibrous tissue interspersed with chondrocytes. It is also found in the intervertebral discs, pubic symphysis, and some sites of ligament attachment It enhances the strength of the structure.
White fibrous cartilage