Cell Systems

Intermediate Filaments

Protein bundles providing rigidity and strength to cells.

Actin Cytoskeleton

Dynamic structure aiding in cell movement and shape.

Microtubules

Hollow structures aiding in organelle transport and cell division.

collagen V

Fibrous protein that gives the skin form and strength

collagen ii

hyaline cartilage

Collagen IV

basal lamina

Collagen 1

most abundant: tendons, skin, artery walls, myofibrils, fibrocartilage, bones/teeth

Vitamin C

An important substance needed for proper repair of the skin and tissues; promotes the production of collagen in the skins dermal tissues; aids in and promotes the skins healing process.

Glycosylation of Collagen

Addition of carbohydrates for stability of collagen.

Dermatosparaxis

Collagen processing defect leading to skin damage.

Ehlers-Danlos Syndrome

A group of inherited disorders that affect your connective tissues — primarily your skin, joints and blood vessel walls.
overly flexible joints and stretchy, fragile skin.

This can become a problem if you have a wound that requires stitches, because the skin often isn't strong enough to hold them.

Mammary Epithelial Cells

single layer of epithelial cells that are primarily responsible for the secretion of milk and actively synthesize and secrete milk constituents into the alveoli

Chondrocytes

cartilage cells
dormant chondroblasts

Chondroblasts

Cells forming cartilage templates in bone development.

Osteoblasts

Cells converting cartilage into bone,
secreting type I collagen.
and calcium and phosphate to mineralize the bone

Osteoblasts function

they secrete collagen I which forms tough fibres called osteoid onto ECM produced by chondrocytes
secrete vesicles containing calcium and phosphate into ECM
they burst and become see site for the formation of hydroxyapatite (salt)

Osteoclasts

Cells breaking down bone, essential for remodeling.
secrete protease and acid to break down bone
seal themselves to the bone surface forming a digestive zone
inhibited by oestrogen

Chondrodysplasia

Genetic syndrome
promotes cartilage to bone conversion
causes unprotortional growth, growth plate converts to bone too fast, limiting growth
in dachshunds, corgus, and bulldogs
as age - osteoarthritis, and spinal arthritis

Osteoporosis

loss of bone density that can result in an increased risk of fractures

Bone Density

Regulated by balance of osteoblast and osteoclast activity.
affected by mechanical stress and calcium balance

Parathyroid Hormone (PTH)

raises blood calcium level
it increases osteoclast activity leading to loss of bone density

Growth Hormone (GH)

Stimulates bone growth and regulates cell proliferation.

IGF-1

Insulin-like growth factor, promotes cell growth and division.
made by liver

IGF-1 activation

- binds to IGF-1 receptors at the surface of cells
- triggers a conformational change in the receptor that activates it
- leads to a chain of signals in the cell and activation of the Akt protein
- Akt activates mTORC1 -which is the major controller of cell growth

Quiescent cells

are non-dividing cells. can be triggered to enter the cell cycle.

hypertrophy

increase in cell size

proliferating cells

continuous cell cycle
stem cells, meristem cells, cancer cells

Myostatin

inhibits muscle growth, by inhibiting Akt
a hormone

Hyperplasia

increase in number of cells

Apoptosis

Programmed cell death, removing unwanted or damaged cells
removed by phagocytic cells

Phagocytosis

Process of engulfing and digesting apoptotic cell fragments.

Bovine Growth Hormone

Increases milk yield by inhibiting involution, which is controlled by mammary cell apoptosis.
increases IGF-1

Enzymes

Biological catalysts that reduce activation energy

Penicillin

Antibiotic that inhibits bacterial cell wall synthesis

Cytoskeleton

Cellular structure supporting cell shape and movement

intermediate filaments function

give shape and physical support to cell; anchor cells to each other and to extracellular material; compartmentalize cell contents

Keratin Filaments

Structural proteins supporting epithelial cells

Desmosomes

Cell connections anchoring epithelial cells together

Epidermolysis Bullosa Simplex

Genetic disorder affecting keratin filaments

What is the main function of the Actin Cytoskeleton?

Supporting cell movement and shape

Describe the equilibrium of Actin Cytoskeleton in the cell.

Exists in a dynamic equilibrium between free monomers and polymerized filaments

Name some cellular processes facilitated by the Actin Cytoskeleton.

Cell migration, phagocytosis, and cytokinesis

How does the Actin Cytoskeleton contribute to cell strength?

Strengthens the plasma membrane, forms a mesh beneath it, and is linked together by proteins; especially strengthens Red Blood Cells (RBCs)

What are microtubules?

Hollow tubular structures aiding cell division and organelle movement

How do microtubules move things around in a cell?

They are connected to all organelles through motor proteins, which move the organelles through the cell and position them within the cytoplasm

How do microtubules grow within a cell?

They grow from the center of the cell (MTOC) and radiate outwards to the plasma membrane

What is the structure of microtubules?

They are polymer of small tubulin monomers forming a hollow tube

junction epidermolysis bullosa

genetic disorder, in horses known as Red Foot disease, first sign are blistering in gums and tongue 12% of Belgian draft horses carry also seen rarely in dogs, sheep, cattle