Topic 8 Flashcards
Specialised cells
What are the main functions of blood?
- Transport
- gases O2, CO2
- nutrients + waste - Regulation
- temp
- pH
- electrolytes - Protection
- wounds
- infections
What are the major cell types of blood?
- erythrocytes (rbc)
- wbc
- thrombocytes (platelets)
What is the process of differentiation of blood cells from stem cells?
- totipotent cells
- pluripotent cells
- multipotent cells
- unipotent cells
- progenitor cells
Define excitable cell.
Cells that respond to external stimuli through a rapid + reversible alteration to electrical potential of their cell membrane
What is the way that neurotransmitters facilitate transmission of an impulse across a synapse?
s
What is the sliding filament theory?
Muscle contraction
- ATP binds to myosin head, that is released from actin filament
- Hydrolysis of ATP cocks myosin head
- Myosin head attaches to an actin binding site
- Power stroke slides actin (thin filament) towards sacromere
How does the sliding filament theory account for muscle cell shortening by up to a 1/3 of its length when in a contracted state?
both thick + thin filament slide past each other
How is the arrival of a nerve impulse at a neuralmuscular junction leads to the muscle undergoing contraction?
neurotransmitter cause muscle contraction
Various means of generating ATP in contracting muscle cells?
s
What is the metabolic diversity of life and adaptations to extreme environments?
s
Identify 4 of rapid immune response of innate cells.
- Anatomical defences
- Physiological defences
- Phagocytic defence
- Inflammatory defence
What is the diversity of interferon pathways used for cell signalling?
s
Describe motor proteins in intracellular movement.
Kines
Describe whole cell movement in biology.
s
What is the role of flagella in cell movement for prokaryotes?
- allow for whole cell movement in prokaryotes
- whip structure
- rotating engine up to 1000rpm at anchoring point in inner cell membrane
What is the role of chemotaxis in immune cells for eukaryotes?
- site of injury => to repair tissue damage
- site of infection => to clear pathogen
- drain lymph nodes => interact with other cells to present antigen to T + B cells
What is the transport functions of the blood?
- primary transport method moving substances around body
- O2 + nutrients to tissues
- CO2 + waste from tissues
- hormones from endocrine glands => target tissues
What are the regulation functions of the blood?
Temp: - maintain body temp. - remove heat from active tissues and transport => skin for dissipation - vasodilation/constriction allows for heat dissipation pH: - maintained 7.35-7.45 - controlled by bicarb. buffer system - carbonic anhydrase Electrolytes: - kidneys filter blood - entire V - 20-25x per day - remove excess waste products + excess fluids
What are the protection functions of the blood?
WOUND HEALING:
- platelets + clotting factors
- prevent blood loss after injury
- deficient in hemophilia
What is totipotent cells in the process of differentiation of blood cells from stem cells?
- fertilised egg + first few divisions
- ability of single isolated cell to produce individual
- begin to differentiate after 5-6 days
- inner cell
eg blastula + blastocytes => pluripotent
What is pluripotent cells in the process of differentiation of blood cells from stem cells?
- embryotic cells
- totipotent => multipotent
- 3 germ layers:
1. endoderm - internal layer eg lung + thyroid cells
2. mesoderm - middle layer eg cardiac muscle cells + red blood cells
3. ectoderm - external layer eg skin cells of epidermis, neurons of brain
What is multipotent cells in the process of differentiation of blood cells from stem cells?
- most adult stem cells
- differentiate into multiple, limited cell types (multi-lineage differentiation)
eg/ tissue stem cells & cord blood stem cells
What is unipotent cells in the process of differentiation of blood cells from stem cells?
- multipotent => unipotent
- 1 cell type
- self-renew + give rise to 1 cell type
eg/ muscle stem cells + epithelial cells
What is progenitor cells in the process of differentiation of blood cells from stem cells?
- arise from different stem cells
- no renewal
- rise to multiple cells
final cell types: - terminally differentiated
- do not divide
eg/ hematopoietic cells
