Exam 2 Flashcards
Adipose Tissue
- Fatty tissue
- Made of adipocytes (fat cells)
- Functions:
- Energy storage
- Insulation
- Protection
Anaphase
- Third phase of Mitosis.
- Chromosomes are being split
- Spindle poles act like vacuums
Apocrine
- a.k.a. mammary glands
- Accumulate secretions that are released when a portion of the cell pinches off
Apocrine Cells
- Found in axillary and anogenital areas
- Larger than eccrine glands
- Secrete a substance made out of sweat, fatty substances, and protein
- Function: no human function; helps animals identify themselves
Arrector Pili
Muscle attached to the hair follicle and dermis that raises the hair when it contracts
ATP
- The most common form of chemical energy.
- Is used in active transport and is made by mitochondria.
Cell Theory
- The cell is the basic structural and functional unit of life
- everything begins at the cellular level
- Organismal activity depends on the individual and collective activity of cells
- Types of cells determine function
- Biochemical activities of cells are dictated by subcellular structures (organelles)
- Continuity of life is based on cells
Cells
Basic structural and functional unit of life
Centriole
- Small barrel-shaped organelles located in the centrosome near the nucleus
- Look like pasta noodles
- Pinwheel array of 9 triplets of microtubules
- Play major role in reproduction
- Produce spindles to organize chromosomes during mitosis
Ceruminous Glands
- modified apocrine glands in external ear canal that secrete cerumn (ear wax)
- Function: protection and blocks out pathogens and dirt
Chromosome
- Composed of DNA and proteins
- Contains primary genetic info of cell
- 23 pairs in humans
- Found in nucleus
Cilia
- Tiny hair-like projections that swishes things across like a wave
- Flagellum is a tail-like projection that propels the cell forward -found in sperm
- Move substances in one direction across cell surfaces
Collagen Fibers
- Resemble ropes
- Strong and flexible but resist stretching
Columnar
- Epithelial cells that are taller than they are wide
- Resemble columns
Connective Tissue
- Distinguished by its extracellular matrix
- Functions:
- Enclose and separate organs and tissues
- Connect tissues to one another
- Support and move body parts
- Store compounds
- Cushion and insulate the body
- Transport substances
- Protect against toxins and injury
Cuboidal
- Epithelial cells that are as wide as they are tall
- Look like cubes
Cutaneous Membrane
- A.k.a. skin
- biggest membrane/organ in body
- 18 square feet
Cytokinesis
- Last phase of mitosis
- Division of the cytoplasm
Cytosol
- Mainly water with dissolved proteins, salts, sugars and other solutes
- 70-80% water
- 10-20% protein
- 2% lipid
Dermis and Layers
- Papillary layer has projections called dermal papillae and is composed of loose connective tissue that is well supplied with capillaries
- Reticular layer is the main layer
- Dense irregular connective tissue consisting mostly of collagen
Diffusion
Tendency for solute molecules to move from an area of high concentration to an area of low concentration in solution
DNA
- Type of nucleic acid containing deoxyribose
- Found in nuclei of cells
- Constitutes genetic material of cells
DNA Replication
- Interphase is the period between cell divisions and is the time where DNA is replicated
- During replication, DNA unwinds, and each strand produces a new DNA molecule
Eccrine Glands
- Found in palms, soles, of the feet, and forehead
- Simple coil-liked tubes
- Function: release sweat via exocytosis
- 90% water
- Almost same makeup as plasma
- Genetics, diet, activity level determine amount of sweat
Elastic Fibers
- Type of protein fiber
- Similar to springs (like in a bed)
- Tend to return to original shape
Endocrine Glands
-Release hormones that are absorbed directly into the blood
Endomembrane system
- System of organelles that function to:
- Produce, store, and export biological molecules
- Degrade potentially harmful substances
- System includes
- Nuclear envelope
- smooth and rough ER
- lysosomes
- vacuoles
- transport vesicles
- Golgi apparatus
- plasma membrane
Endoplasmic Reticulum
- Interconnected tubes and parallel membranes enclosing cisternae
- Complex membrane system running from nucleus to plasma mebrane
- Functions:
- Transportation
- Storage
- Continuous with the nuclear membrane
- Two varieties:
- Rough ER
- Attachment of ribosomes
- Bedazzled with ribosomes
- Manufacture and secrete all proteins
- Responsible for producing proteins and phospholipids for membrane
- Smooth ER
- Produce steroids
- Tubules arranged in a looping network
- Catalyzes following reactions
- Liver: lipid and cholesterol metabolism, breakdown of glycogen and, along with the kidneys, detoxification of drugs
- Testes: production of steroid-based hormones
- Intestinal cells: absorbtion, synthesis, and transport of fats
- Skeletal and cardiac muscle: storage and release of calcium
- Rough ER
Endothelium
!!
Epidermis
- Made of stratified Squamous cells
- Divided into five layers
- stratum basale
- stratum spinosum
- stratum granulosum
- stratum lucidum
- stratum corneum
Epithelia Tissue
!!
Epithelial Tissue
- Consists of cells with little extracellular matrix
- Covers surfaces, has a basement membrane, and has no blood vessels
- Functions:
- Protects underlying structures
- Acts as a barrier
- Secrete substances
- Absorb substances
- Types are simple, stratified, pseudostratified, squamous, cuboidal, or columnar
Exocrine Glands
- More numerous than endocrine glands
- Secrete their products onto body surfaces (skin) or into body cavities
- Mucous, sweat, oil, salivary glands
- Only important unicellular gland is the goblet cell
- Multicellular exocrine glands are composed of a duct and secretory unit
- Classified according to:
- Simple or compound duct type
- Structure of their secretory units
Exocytosis
- Secretion of materials from cells by vesicle formation
- Move substances from the cell interior to the extracellular space
Fingernails
- Nail root is covered by skin, and the nail body is the visible part of the nail
- Nearly all of nail is formed by nail matrix, but nail bed contributes
- Nail is stratum corneum containing hard keratin
- Function is to protect ends of fingers
Fibrocartilage
- Contains collagen fibers in thick bundles
- Can withstand great pressure
- Found between vertebrae, in the jaw, and in the knee
Flagella
- Long hair-like projections similar to cilia
- Propel sperm cells
Hair
- Three parts: shaft, root, and hair bulb
- Root and shaft made of dead keratinized epithelial cells
- Color is determined by amount of melanin
- Hair bulb produces hair in cycles of growth and rest
- Protects against abrasion and ultraviolet light and is a heat insulator
Hair follicles
- Root sheath extending from the epidermal surface into the dermis
- Deep end is expanded forming a hair bulb
- A knot of sensory nerve endings ( a root hair plexus) wraps around each hair bulb
- Bending a hair stimulates these endings, hence out hairs act as sensitive touch receptors
Holocrine Cells
Cells that have filled up with substance and are about to rupture
Human cells
!!
Hypertonic Solutions
- Solutions having greater solute concentration than that of the cytosol
- Ex: drinking salt water
- Water diffuses out of cells. Cells shrink
Hypodermis
-Subcutaneous layer deep to the skin
-Composed of adipose and areolar connective tissue
-Function:
-Shock absorption
=Insulation
-Rich supply of energy
-Regulates temperature
Hypotonic solutions
- Solutions having lesser solute concentration than that of the cytosol
- Water diffuses into the cell. Cell swells
Keratin
!!
Keratinocytes
- produce the fibrous protein keratin
- Scale-like in appearance
- Most common cells found in epidermis
Langerhans Cells
- epidermal macrophages that help activate the immune system
- Come from immune system
Layers of Epidermis
- Stratum basale: made of keratinocytes
- Stratum spinosum: made of several layers of cells held together by many desmosomes
- Stratum granulosum: made of cells filled with granules of keratohyalin (cell death occurs here)
- Stratum lucidum: made of a layer of dead, transparent cells
- Stratum corneum: made of many layers of dead squamous cells
Lunula
- Part of the nail matrix visible through the nail body
- Whitish, cresent-shaped area at the base of the nail
- This is because it is too thick for the blood vessels to show through
Lysomes
-Spherical membranous bags containing digestive enzymes
“garbage disposals”
-Digest ingested bacteria, viruses, and toxins
-Degrade nonfunctional organelles
-Breakdown glycogen and release thyroid hormone
-Breakdwon nonuseful tissue
-Breakdown bone to release Ca2+
-Secretory lysosomes are found in white blood cells, immune cells, and melanocytes
Make up of cells
- Plasma membrane
- Cytoplasm
- Nucleus
- Ribosomes
- Endoplasmic Reticulum
- Golgi Apparatus
- Secretory Vesicles
- Lysosomes
- Peroxisomes
- Proteasomes
- Mitochondria
- Centrioles and Spindle Fibers
- Cilia and Flagella
- Microvilli
Mammary Glands
- a.k.a. apocrine glands
- Accumulate secretions that are released when a portion of the cell pinches off
Meioses
-Production of gametes or sex cells
Melanocytes
- Produce melanin
- Amount determines skin color
Merkel Cells
- function as touch receptors in association with sensory nerve endings
- Half-hemisphere shape
Merocrine Cells
- a.k.a. pancreas
- Secrete substances as they are produced
Metaphase
- 2nd phase of mitosis
- Chromosomes are lined up in the middle
Microtubules
- Hollow, slender, cylinder shaped tubes
- Function:
- Assist in movement of cilia and flagellum and help move chromosomes
- Help in mitosis
Microvilli
- Tubular extensions of the plasma membrane
- Made out of protein Actin
- Function:
- Absorption and provides huge surface area
- Found in small intestine
Mitochondria
- “powerhouse” of the cell
- Double membrane structure with shelf -like cristae
- Provide most of the cell’s ATP via aerobic cellular respiration
- Contain their own DNA and RNA
Mitosis
- Nuclear division
- Essential for body growth and tissue repair
Mucous Membrane
- Made of epithelial cells, basement membrane, lamina propria, and smooth muscle cells
- Line cavities that open to the outside and contain mucous glands which secrete mucus
Muscular Tissue
- Has ability to contract
- Functions:
- Movement
- Pump
- Protection
- Involuntary and voluntary
Nucleoli
-Made of RNA and proteins and are sites of ribosomal subunit assembly
Organs
-Composed of two or more tissues that perform specific functions
Osmosis
- Diffusion of water across a selectively permeable membrane
- Isotonic (cell stays same), hypertonic (cell shrinks), hypotonic (cell swells)
Papillary layer
- Layer of the Dermis
- Has projections called dermal papillae and is composed of loose connective tissue that is well supplied with capillaries
Passive Membrane Transport
- Simple diffusion: nonpolar and lipid-soluble substances
- Movement of particles across a semi-permeable membrane
- Diffuse directly through the lipid bilayer
- Diffuse through channel proteins
- Facilitated Diffusion:
- Transport of glucose, amino acids, and ions
- Transported substances bind carrier proteins or pass through protein channels
- Assisted diffusion
- Getting amino acids into the cells to keep building tissues
Peroxisomes
- Membrane-bound sacs
- Have enzymes that digest fatty acids and amino acids
- Have enzymes that catalyze the breakdown of hydrogen peroxide
Phagocytosis
-Bulk movement of solid materials into cells by the formation of a vesicle
Makeup of Plasma Membrane
Phospholipid bilayer where proteins are suspended (fluid-mosaic model)
Plasma Membrane Function
Passively or actively regulates what enters or leaves the cell (forms outer boundary of the cell)
Potassium
!!
Prophase
- 1st phase of mitosis
- Chromatin condense to chromosomes
- Centrioles move to opposite poles of cell
- Astral and spindle fibers form
- Nuclear envelope breaks apart
Pseudostratified
False layers; looks like multiple layers but is really only one
Reticular Fibers
- Fine collagen fibers that form branching network that supports cells and tissues
- Type of protein fiber
Reticular Layer
- Main layer of the dermis
- Dense irregular connective tissue made up of mostly collagen
Ribosomes
- Made of large and small subunits
- Sites of protein synthesis
- Can be free or on rough ER
RNA
- Carry instructions from DNA to ribosome for protein synthesis
- Reverse of DNA
Root Hair Plexus
A knot of nerve endings wrapped around each hair bulb
Sebaceous Glands
- a.k.a. holocrine glands
- Accumulate secretions that are released when the cell ruptures and dies
Serous Membranes
- Line cavities that do not open to the exterior
- Do not contain glands that secrete fluid
Simple
Single layer of epithelial cells
Skin
!!
Squamous
Flat epithelial cells with no regular pattern
Stratified
Two or more layers or epithelial cells
Stratum Corneum
- One of five layers of epidermis
- Made of many layers of dead squamous cells
Straum Germinativum
- Deepest epidermal layer firmly attached to the dermis
- Consists of a single row of the youngest keratinocytes
- Single layer of cubed shaped cells
- 50% are melanocytes
- Function: Anchor epidermis to the dermis and produce melanin
- A.k.a. stratum germinatum layer because cells undergo rapid division
- Got the most oxygen and nutrients (where mitosis takes place)
Sudorifer Glands
!!
Telophase
- 4th and last phase of mitosis
- Chromosomes unravel to become chromatin
- Nuclear envelope and nucleoli reappear
Terminal Hair
- Replaces lanugo (fetal) hair
- Long, coarse, and pigmented hairs
Tissue Repair
Cell division
Tissues
- Embryonic, epithelial, connective, muscle, and nervous
- Made up of two or more cells
Vellus Hairs
-Short, fine, and unpigmented hair
Vernix Caseosa
- Stuff on babies when they are born
- produced from sebaceous glands
