A&P Quiz 2 Flashcards
What is the role of the nucleus?
Control center of the cell; contains genetic information and controls protein synthesis
Surrounded by a double-layered nuclear membrane
What is nucleoplasm?
A gel-like substance found inside the nucleus
What is the nucleolus?
Involved in the synthesis of ribosomes and RNA
“little nucleus”
What is chromatin?
Thread-like structure that contains genes
How many nuclei do most adult cells have?
One nucleus; mature RBCs have no nucleus
What is the function of the cell membrane?
Contains cellular contents; selects what enters and leaves the cell
What are cilia?
Hairlike projections that move substances across the surface of the cell membrane
What is the function of the flagellum?
Single long hair for swimming movement of the sperm
What are microvilli?
Accordion-like folds in the membrane that increase transport of water and dissolved solute
What is cytoplasm?
Gel located inside the cell but outside the nucleus
What is cytosol?
Medium composed of water and dissolved solute; organelles suspended in the cytosol
What do mitochondria do?
Site of adenosine triphosphate production; ‘power plants’ of the cell
What is the rough endoplasmic reticulum (ER)?
Contains ribosomes where protein is synthesized
What is the smooth endoplasmic reticulum (ER)?
Site of lipid and steroid synthesis; synthesis of glycogen in liver and skeletal muscle
What is the function of the Golgi apparatus?
Finishes and packages protein for export
What are lysosomes?
Intracellular house cleaning, phagocytosis, removal of damaged organelles
What is the cytoskeleton?
Microfilaments and microtubules that provide for intracellular shape, support, and movement
What are centrioles?
Paired, short, rod-shaped microtubules that form spindles and help separate the chromosomes during mitosis
What are inclusion bodies?
Temporary insoluble material such as glycogen granules and pigments such as melanin
What is the composition of the cell membrane?
Mainly composed of phospholipids (bilayer) and proteins
Semi-permiable membrane. Lipid-soluable substances (O2, CO2) can dissolve to move across, but water soluable substance (water and electrically charged substances) must use the pores
What is tonicity?
Ability of the concentration of a solution to affect the volume and pressure within a cell
What is an isotonic solution?
Has the same concentration as intracellular fluid; no net movement of water occurs
What is a hypotonic solution?
Hypotonic solution (less than 0.9% salt)
Causes RBCs to burst (hemolysis) when placed in pure water
What is a hypertonic solution?
Hypertonic solution (higher than 0.9% salt)
Causes RBCs to shrink (crenate) when placed in a very concentrated salt solution
What are the phases of the cell cycle?
Interphase (G1, S, G2) and Mitosis (Prophase, Metaphase, Anaphase, Telophase)
What is cell differentiation?
Process where unspecialized stem cells become specialized cells needed by various tissues
What is apoptosis?
Programmed cell death that helps rid the body of old, unnecessary, and unhealthy cells
What are the four major types of tissues?
- Epithelial
- Connective
- Nervous
- Muscular
What are the characteristics of epithelial tissue?
Forms continuous sheets; avascular; regenerates quickly if injured
For its nourishment, it depends on the blood supply of the underlying connective tissue.
How is epithelial tissue classified?
According to shape (squamous, cuboidal, columnar) and number of layers (simple, stratified, pseudostratified)
What are exocrine glands?
Use ducts to carry secretions outside the body
Example: Mucus, tears, digestive enzymes, sweat and salivary glands
What are endocrine glands?
Ductless glands that secrete hormones directly into the blood
Example: Adrenal gland and pancreas
What are the functions of connective tissue?
Connection, support, transportation, protection, fat storage
What are the types of connective tissue?
- Loose (areolar, adipose)
- Dense (reg, irreg)
- Specialized
ADD: Bone, blood, lymph
What are the three main types of connective tissue?
Tendons, ligaments, and cartilage
These connective tissues have varying amounts of protein fibers.
What is the primary protein fiber found in connective tissue?
Collagen
Collagen provides strength and structure to connective tissues.
What is the function of elastin in connective tissue?
Provides elasticity
Elastin allows tissues to return to their original shape after stretching.
What type of connective tissue is characterized by a loose mixture of cells and fibers?
Loose connective tissue
This type is abundant throughout the body.
Where is areolar connective tissue primarily located?
Around organs and vessels, in membranes, under skin
Areolar tissue provides support and protection.
What is the primary characteristic of adipose tissue?
Soft matrix that provides support and protection
Adipose tissue stores fat and insulates the body.
What describes dense regular connective tissue?
Mostly collagen fibers in parallel alignment
This structure provides great tensile strength in one direction.
What is the location of dense irregular connective tissue?
Fascia, capsules around organs
This type of tissue provides strength in multiple directions.
What is cartilage formed by?
Chondroblasts that mature into chondrocytes
These cells are responsible for producing the cartilage matrix.
What are the three types of cartilage?
Hyaline, Fibrocartilage, Elastic
Each type has distinct properties and functions.
What is the term for bone tissue?
Osseous tissue
Bone provides structural support and protection.
What do osteoblasts do?
Secrete a solid matrix hardened with mineral salts
This process is essential for bone formation.
What is the basic unit of nervous tissue?
Neuron
Neurons are responsible for transmitting nerve impulses.
Name the parts of a neuron.
Dendrites, Cell Body, Axons
Each part has a specific role in nerve impulse transmission.
What is a nerve?
A bundle of nerve fibers held together with connective tissue
Nerves facilitate communication within the nervous system.
What is the function of neuroglia?
Support and protect nervous tissue
Do not transmit nerve impulses
Neuroglia also perform various maintenance functions.
What are the two types of tissue repair?
Regeneration, Fibrosis
Regeneration involves mitosis, while fibrosis results in scar tissue.
What are the steps in tissue repair after an injury?
A. Wound, B. Clot and scab, C. Tissue repair begins, D. Scar tissue forms, E. Epithelial cells multiply, F. Scab detaches
Epithelial tissue regenerates quickly after injury.
What is the function of serous membranes?
Line body cavities and cover internal organs
Examples include pleurae, pericardium, and peritoneum.
What do mucous membranes line?
Tubes and ducts that open to the outside of the body
Mucous membranes secrete mucus for lubrication and protection.
True or False: Mucous membranes trap and remove foreign particles.
True
They also protect deeper tissues and absorb food materials.
What is the ER?
Membranes that form channels for the flow of cellular substances such as proteins
What are the function of ribosomes?
Site of protein synthesis
Free: Ribosomes that float within the cytosol; make protein used within the cell
Fixed: Ribosomes fixed to the ER, making it appear rough; concerned with the synthesis of protein that is exported
____ transport mechanisms require no additional input of energy in the form of ATP.
Passive
____ is the most common transport mechanism. It is the movement of a substance from an area of higher concentration to an area of lower concentration.
Diffusion
EX: Diffusion of oxygen and carbon dioxide across the alveolar cell membrane in the lung.
____ is a form of diffusion that is responsible for the transport of many substances. Substances move from a higher concentration toward a lower concentration. However, the substance is helped across the membrane by a molecule within the membrane and the helper molecule increases the rate of diffusion.
Facilitated diffusion
____ is a special case of diffusion. Osmosis is the diffusion of water through a selectively permeable membrane.
Osmosis
EX: During osmosis, the water diffuses from an area with more water to one with less
With ____, water and dissolved substances cross the membrane in response to differences in pressure. In other words, pressure pushes substances across the membrane.
filtration
EX: Where does filtration occur in the body? The movement of fluid across the capillary wall can be compared with the movement of water in the syringe with holes in its side
____ transport mechanisms require an input of energy in the form of ATP. It is like the upward movement of a ball.
Active
____ is a transport mechanism that involves the intake of food or liquid by the cell membrane. The particle is too large to move across the membrane by diffusion. Instead, the particle is surrounded by the cell membrane, which engulfs it and takes it into the cell.
Endocytosis
Two types
If the endocytosis involves a solid particle, it is called ____.
phagocytosis (phago- means “eating”).
For example, white blood cells eat, or phagocytose, bacteria, thereby helping the body defend itself against infection.
If the cell ingests a water droplet, the endocytosis is called ____
pinocytosis, or “cellular drinking.”
____ moves substances out of the cells.
Exocytosis
During this phase, the cell carries on its normal activities and begins to make the DNA and other substances necessary for cell division.
Interphase
First gap phase (G1)
During interphase, the cell carries on with its normal functions and gets ready for mitosis through growth and DNA replication.
The cell duplicates its chromosomes, thereby making enough DNA for two identical cells.
Interphase
Phase S
During interphase, the cell carries on with its normal functions and gets ready for mitosis through growth and DNA replication.
This phase is the final preparatory phase for cell division (mitosis); it includes the synthesis of enzymes and other proteins needed for mitosis. At the end of this phase the cell enters the mitotic (M) phase.
Interphase
Second gap phase (G2)
During interphase, the cell carries on with its normal functions and gets ready for mitosis through growth and DNA replication.
During the mitotic (M) phase, the cell divides into two cells in such a way that the nuclei of both cells contain identical genetic information. ____ consists of four phases: prophase, metaphase, anaphase, and telophase
Mitosis
During ____, the chromosomes coil so tightly that they become visible under a light microscope. Each chromosome pair is composed of two identical strands of DNA called chromatids; each chromatid is attached at a point called the centromere. At the same time, two pairs of centrioles move to opposite poles of the nucleus. Late in this phase, the nuclear membrane disappears.
prophase
Mitosis
During ____, the chromatids are aligned in a narrow central zone; spindle fibers connect the chromatids and centrioles.
metaphase
Mitosis
____ begins when the centromere splits and the chromatids are pulled to opposite poles (end of anaphase).
Anaphase
Mitosis
During ____, each new cell reverts to the interphase state; the nuclear membrane reforms, the chromosomes uncoil, and the chromatin strands reappear.
Telophase
Telophase and cytokinesis mark the end of mitosis.
____ which begins in late anaphase, is the pinching of the cell membrane to split the cytoplasm into two distinct cells.
Cytokinesis
Telophase and cytokinesis mark the end of mitosis.
The ____ epithelium cells are thin and flat.
squamous
Simple squamous allows for the rapid diffusion of O2 from the alveoli in the lungs to the blood
The ____ epithelium cells are cubelike and look like dice.
cuboidal
Simple cuboidal: located in kidney tubules & glands
The ____ epithelium cells are tall and narrow and look like columns.
columnar
Simple columnar line the digestive tract
Stratified epithelium is…
Multilayered
Stronger because of the layers
Tissue exposed to wear and tear
- Stratified Squamous loctaed in the mouth, esophagus, skin, organs that stretch
- Transitional located in the urinary bladder
Intercellular matrix
Consists of ground substance and protein fibers. The ground substance is the material between the cells and fibers. The hardness and amount of the matrix varies from one tissue type to the next.
The matrix of most connective tissue contains protein fibers: collagen fibers, elastic fibers, and reticular fibers (fine collagen). The fibers strengthen and support connective tissue.
Most abundant in connective tissue
Varies from liquid to hard
Most is well vascularized; exceptions: tendons, ligaments, and cartilage
