Week 7 (exam 2) Flashcards
What are the 2 basic processes of the cell life cycle or cell cycle and explain them
1) cell division- single cell splitting into 2 identical daughter cells
2) Apoptosis- natural cellular death
What is mitosis?
Division of nucleus and the chromosomes the nucleus contains
Used to mean cell division
What is cytokinesis?
When cell splits into daughter cells
What are the 4 events of the cell cycle?
1) M phase or Mitotic
2) G1
3) S
4) G2
What is the M phase or Mitotic of the cell cycle?
Cell division
Daughter cells double numbers of organelles (mitochondria, nucleus, etc) to bring back to correct number and accumulate materials needed
What is the G1 phase of the dell cycle?
To copy DNA
What cells are too large and complex, stop at G1 phase and are described as perpetual (G0)?
Neurons (nerve cells) and skeletal muscle cells
What is perpetual mean?
Go on forever
What is the S phase of the cell cycle?
DNA is copied
Not visible under microscope
Semiconservative synthesis of DNA
What is semiconservative synthesis of DNA mean?
Duplicate of DNA
Genetically identical cells are called what?
Daughter cells Or Clones
Before mitosis or m phase finishes what happens?
Cytokinesis
What stages of the events in a cell cycle are called interphase and why?
G1, S and G2
Not much visibly seen under microscope
What helps the process of mitosis or m phase?
Chemical signals inside and outside the cell
What is a checkpoint?
Built in the cell cycle to stop cycle if something that needed to be accomplished is not
Cycle has to happen in orderly fashion and not too quickly
What does the checkpoint in the middle of the M phase do?
If chromosomes are not properly aligned the checkpoint holds everything until the chromosomes are properly aligned
What does the checkpoint in phase G1 do?
Cell examines DNA to make sure it is not damaged
If there is damage (mutations) the cell attempts to repair to DNA if cannot be repaired cell initiates apoptosis
What is the G2 phase of the fell cycle?
Getting ready for another cell division (M phase)
Gathering material
Use microtubules so you have to accumulate tubulin protein
What is p53?
Protein responsible for checkpoint in G1
What happens if p53 is unable to be produced?
Without p53 checkpoint in G1 disappears
That means cycle will continue even if DNA isn’t copied correctly
How rumors appear in people because a genetic mutation appears
What does prophase do?
Beginning of prophase chromosome condense together and starts to look like big butterfly, little butterfly or house fly
Nuclear envelopes break down
Chromosomes move to middle of cell
Centrioles (2) move polar ways and create spindle
What is polar?
Centrioles move in opposite directions on the side of the cell
What happens during the metaphase stage?
The chromosomes align along imaginary midline of the cell (metaphase plate)
Centrioles are now on the opposite sides of the cell
Chromosomes attach to spindle by centromeres (dot in chromosome)
Spindle passes through line of chromosomes
What is the metaphase plate in metaphase?
Imaginary midline between the cell
What happens during the anaphase stage?
Chromosome break in half and follow microtubulles rapidly moving to opposite sides
What are the daughter cells called when split in half and move in opposite direction?
Daughter chromosome
What happens during the telophase stage?
Begins: all motion stops
Chromosomes reach destination (opposite sides of cells) (polar)
Cytokinesis happens
(Can see in microscope)
When cell splits each one gets same stuff
What is the cytokinesis cleavage furrow?
The dent between cell that deepens as cell splits
What are the 4 basic kinds of tissues?
1) Epithelium
2) connective tissue (CT)
3) muscle
4) nerve
What is epithelium tissue?
Forms membranes and glands
Membranes:
- Protect deeper structure in the body and/ or interface between the body and outside world
- Covering
- Ex: interface in lungs
What are the layers of epithelium and explain
1) simple- one layer
2) stratified- multiple layers
3) pseudostratified- one layer but looks like many
What does the checkpoint at the end of phase G2 do?
Stops cycle until DNA finishes copying itself
What are the stages of M phase or Mitosis?
1) Prophase
2) Metaphase
3) Anaphase
4) Telophase
PMAT
What are the shapes of epithelium tissue and explain
1) squamous- rectangle
2) cuboidal- square shape
3) columnar- night greater than width (rectangle standing up)
What is the apical surface?
Upper surface of the cell
What is the basement membrane or Basal Camina?
Bottom layer of cell separating Epithelium tissue and CT
Need anchoring junction or desmoses to attach
How are glands formed?
Form from unfolding (pockets) in epithelium
What is a gland with a duct called?
Exocrine Gland
What is a gland without a duct called and what does it release?
Endocrine Gland
Release secretions (hormones) in blood
What are hormones?
Chemical messengers
What are 3 modes of secretion of the exocrine gland (how gland secretes)?
1) Merocrine (most common)
2) Apocrine
3) Holocrine
What is merocrine secretion?
Secret materials using secretory vesicles that migrate to the cell membrane
Ex: sweat glands
Mucin + water = ?
Mucus
What is Apocrine secretion?
Top part of gland dumps all materials out and disappears
Ex: mammory glands- glands that produce milk
What is holocrine secretion?
The whole cell is packed with secretory vesicles and whole cell blows out letting all material out (huge quantity)
Ex: sebaceous gland- oily glands of hair
What do the glands secrete and explain?
1) serous glands- watery liquid often containing enzymes
2) mucous gland- secrete mucin
3) mixed exocrine secretion-
Produce both
1 secrets mucin other serous
How is the gland built (what does it look like)?
1) unicellular
2) multicellular
What is unicellular?
Consists of only one cell
Goblet cells (only kind in body)- produces mucus in digestive tract
What is multicellular?
Consists of multiple cells
Secretory sheet- unmodified membrane
Outpocketings from membrane (classical kind)
What are the 3 characteristics used to describe glands that form from ourpocketing?
1) shape of the secretory portion of the gland
2) structure if the duct
3) relationship between ducts and the glandular areas
What is the glandular areas?
Part of gland that actually does the secreting
What are the 2 basic kind of shapes of glands?
1) longated and tubular
2) round Alveolar or Acinar
What are the 2 structures of the ducts?
1) simple (one duct)
2) compounded (one duct divided into many)
What is the relationship between the ducts an glands?
Branched- share one duct with glandular areas sharing
What are the simple tubular shapes of glands?
1) simple tubular (longated duct)
2) simple coiled tubular (gland looks like spiral)
3) simple branches tubular (longated glands sharing one duct)
What are the simple alveolar or acinar shapes of the glands?
1) simple alveolar or simple acinar (circle gland)
2) simple branched alveolar or simple branched acinar (circle glands sharing one duct)
What are the compound shape glands?
1) compound tubular (longated glands divided into different ducts)
2) compound alveolar or compound acinar (circle glands divided into different ducts)
What is connective tissue?
All consist of sparsely distributes fella living with non living stuff (matrix- solid, semisolid, liquid)
What are the 3 types of CT?
1) CT proper
2) supporting CT
3) fluid CT
What are the 2 kinds of CT proper?
1) loose- fluid matrix
2) dense- little or no fluid and mostly collagen
- can be irregular or regular
What are the 2 kinds of loose CT proper and explain them
1) Areolar:
- classic kind
- matrix is liquid with cross crossing fiber
- binds everything together under skin
2) Adipose:
- fat tissue
- adipocytes (fat cells)
- can’t spot nucleus if it is on the side
- store triglycerides
- criss crossing protein fibers
What is collagenous tissue?
Formed with collagen
What are the 2 kinds of regular dense CT proper and explain
1) Tendon- muscle to bone
2) ligaments- bone to bone
Both rope like structure
What are the 2 kinds of irregular dense CT proper and explain
1) sheath-
- Ex: periosteum and perichondrium (sheath around cartilage)
2) capsules- joint capsules (synouvial joint)
What are the 3 kinds of protein fibers in CT proper?
1) collagen
2) elastic fibers
3) reticular fibers
What is collagen?
Very common
Long and do not branch
Incredible tensile strength (greater than steel)
What is tensile strength?
Resist breaking when pulled on by opposite ends
What are elastic fibers?
Composed of elastin protein
Branched
Exhibit elasticity
What is elasticity?
Returns to original shape after you stretch it
Ex: rubber band, skin
What are reticular fibers?
Form a network (fisherman net)
Resist pulling from any direction and resists breaking
What are the 2 basic kinds of fat (adipose) and explain
1) yellow or white:
- most fat of human body
- white fat when you’re young turns to yellow as you get older
- major energy storing tissues (store triglycerides)
- keeps body warm
- acts as cushion
- under skin
2) brown fat:
- newborn babies have a lot
- brown color
- maintains body heat
- lot of metabolism going on and has a lot of heat
- metabolic process is aerobic respiration
- generates heat
What are the 2 reason brown fat is brown?
1) Cytochrome pigments- part of electron transport chain
2) Vascularized- equipped with blood vessels (blood gives brown color)
What does supporting CT do and what are the 2 kinds?
Supports framework for the body (forms skeleton)
1) cartilage- semisolid matrix
2) bone- solid matrix
What is translucent?
The matrix of cartilage
Allows light to pass through but you can’t see through it
Fairly flexible
Interlaces with protein fibers mostly collagen
What are chondrocytes?
Cartilage cells that are living and need nutrients and has waste
O2 and Nutrients are diffused in
Waste is diffused out
What are the chambers the cells live in?
Lacunae
What is the anti angiogenesis factor in cartilage?
Chemical secreted by chondrocytes that prevent blood vessels from developing
Lack of blood vessels means hard recovery when damaging a cartilage
A cancer treatment
What are the different kinds of cartilage?
1) Hyaline cartilage- most of our body
2) Fibro cartilage
3) elastic cartilage
4) calcified cartilage
What is fibro cartilage?
Reinforced with extra collagen fiber
Fibers go in same direction
Layer look
Resists compression
Ex: pubis symphysis
What is elastic cartilage?
Numerous elastic fibers
Very flexible but returns to original size and place
Seen in Pinna (ear and nose)
What is calcified cartilage?
Only found in human body when cartilage dies and transforms into bone
Lots of calcium salt (cement like material) deposited in matrix
Shuts down diffusion and cells die
Bone has a matrix of cement made of material mostly in calcium phosphate interlaced with collagen. What is this material called?
Hydroxyapatite
What are osteocytes and what are the chambers they live in called?
Bone cells
Lacunae
What are the rings in bone called?
Lamella
What is a Haversian canal or central canal?
Any of the minute tubes that form a network in bone and contain blood vessels
What is an osteons or haversian system?
Cylinder structure that contain osteocytes connected by canaliculi which transport blood
Thick bone consists of many what?
Osteons or Haverison systems
The 3 kinds of protein fibers are secreted by specialized cells called?
Fibroblasts
