Unit 13: Cell Signalling and Blood Flashcards
The process in which antibodies attach to antigens, causing the formation of masses of linked cells is called:
Agglutination
An individual has previously given birth to a baby. In a subsequent pregnancy, hemolytic disease of the newborn would most likely be a risk in the following case :
1) The person carrying the fetus is A-
2) The person carrying the is AB+
3) The fetus is O-
4) The first child is B-
1) The person carrying the fetus is A-
The SAFEST blood to give to a person with AB- blood is:
AB-
Why are ion channels necessary to transport ions into or out of a cell?
Ions are charged particles and cannot diffuse through the hydrophobic interior of the membrane.
A person living with hemophilia will bleed more easily because they have:
inadequate clotting factors
A patient has been prescribed, warfarin, an anticoagulant. This medication will help to:
reduce blood clotting
In the coagulation cascade, the common pathway occurs:
AFTER both the intrinsic and extrinsic pathway
In some breast cancers, a cell membrane receptor called HER2 is overexpressed (ie. there are more than usual). The dimerization of this protein can cause cell proliferation and growth, which in cancer, leads to tumour growth. Direct treatment for this type of cancer might include:
Medication that binds to HER2 and blocks its signaling
Match the type of signal with its characteristics:
Signals from distant cells
Endocrine
Match the type of signal with its characteristics:
Move by diffusion through extracellular matrix
Paracrine
Match the type of signal with its characteristics:
Intracellular mediators that allow small signaling molecules to move between cells
Gap junction signalling
Match the type of signal with its characteristics:
Signal and target cell are the same
Autocrine
The toxin from this illness enters intestinal cells and modifies a G-protein-linked receptor that controls the opening of a chloride channel. This causes the channel to remain continuously active, resulting in large losses of fluids from the body and potentially fatal dehydration as a result.
Cholera
A cell surface receptor protein would most likely include the following component:
An extracellular domain
Clotting factors are numbered sequentially based on:
The time of their discovery
The insoluble filamentous protein derived from fibrinogen that is essential for clotting is called:
Fibrin
Lupus, sickle cell disease, and pregnancy might all increase the risk of developing:
Thrombophilia
Internal Receptors
- In the cytoplasm.
- Respond to hydrophobic ligand molecules that are able to travel across the plasma membrane.
- The ligand molecules bind to the proteins that act as regulators of mRNA synthesis to mediate gene expression.
- Triggers a conformational change that exposes a DNA-binding site on the protein.
Cell-Surface Receptors
- On cell surface in the plasma membrane.
- Proteins that bind to external ligand molecules that cannot cross the plasma membrane.
Ion Channel-Linked Receptors
- On cell surface in the plasma membrane.
- Bind to a ligand and then a membrane channel opens that allows specific ions to pass through.
- Amino acids line the inside of the channel and are hydrophilic to allow passage of water or ions.
Small Hydrophobic Ligands
- Can directly diffuse through the plasma membrane and interact with internal receptors.
- Includes steroids (like estradiol(form of estrogen), testosterone, cholesterol, and other hydrophobic hormones like thyroid hormones and vitamin D.
Water-Soluble Ligands
- Cannot pass through the plasma membrane unaided (polarity) or at all (some are too large)
- Bind to the extracellular domain of cell-surface receptors.
- This group of ligands is quite diverse and includes small molecules, peptides, and proteins.
Other Ligands
- Nitric oxide (NO) is a gas that diffuses directly across the plasma membrane to interact with receptors in smooth muscle and induce relaxation of the tissue.
- NO has a very short half-life and, therefore, only functions over short distances.
