tricky short answer questions Flashcards
Actin is a fibrous protein involved in the cytoskeleton of the cell. What properties of fibrous proteins make it suitable for its function?
Fibrous proteins are long, insoluble molecules
A pancreas cell wants to make insulin. Which of the following statements are true for the transcription and translation of insulin?
1) The gene for insulin is translated into a strand of messenger RNA.
2) mRNA leaves the nucleus and is translated by a ribosome.
3) Three nucleotides together on mRNA are called a triplet.
4) Three nucleotides together on transfer RNA are called an anti-codon.
2,4
How are enzymes synthesised?
mRNA from the nucleus is transcribed by a ribosome to produce an enzyme.
what types of molecule can diffuse across the plasma membrane
small and non polar
is water polar
yes
why can water diffuse across the plasma membrane even though it is polar
because it is extremely small
A mutation occurs that prevents the synthesis of glycoproteins. What effect would this have on the cell?
Lymphocytes would destroy the cell
because the cell would no longer have ‘self’ antigens
How are lipid-insoluble hormones transported into cells?
endocytosis - transport of large molecules
Solution A has a higher concentration of solutes than solution B. What could solution A be described as compared to the solution B?
hypertonic
What is the purpose of the Casparian strip
Force water across the membrane into the cytoplasm
Which of the following is a sink in a plant?
stems
leaves
meristem
tuber in spring
Meristem - actively dividing
An organism has been described as unicellular, containing a membrane-bound nucleus, and cholorplasts. Classify this organism into the correct kingdom.
Protoctista
Cell wall of fungi
Chitin
Cell wall of bacteria
Peptidoglycan
A person was infected with a structure that contained a cell wall made of murein and there were several flagella present. What would be an effective treatment against this?
Antibiotics
Which type of cells does HIV target?
T cells , specifically t helpers
Impulses are transmitted across synapses. When this occurs the neurotransmitter is released from which part of the synapse?
Synaptic vesicles
By what processes do sodium ions move in and out of the axon
Active transport - out
Carrier proteins - out
Facilitated diffusion - in
The chemoreceptors that detect the need to increase the heart rate are found in which artery?
Carotid artery - serves the brain
What are the small berry like clusters in the liver
Acini - exocrine tissue producing digestive enzymes
Cortisol is an example of a steroid hormone. Which of the following statements about the way it causes its effect on a target cell are true?
A. It is hydrophilic
B. It passes through the lipid component of the cell membrane
C. It forms a hormone-receptor complex which acts as a transcription factor
D. It triggers a cascade reaction triggered by second messengers
B + C
Is haemoglobin a protein or a pigment
Both
How does increased permeability of the collecting duct effect water loss
More water moves out of the collecting duct meaning it is not lost in the urine
A biologist compared two mitochondria of similar size. One was highly folded with many cristae, whereas the other had fewer folds with few cristae.
Which statement about the mitochondria is likely to be true?
A) The number of ATP molecules synthesised in the two mitochondria would be different.
B) Glycolysis takes place in both mitochondria.
C) Oxidative phosphorylation only occurs in the mitochondria which have a highly folded inner membrane.
D) The thicknesses of the mitochondrial membranes of the two mitochondria would be different.
A
Oligomycin is a poison that blocks the proton channel in molecules of ATP
synthase in the mitochondrial membrane. What would be an effect of this
during chemiosmosis?
Facilitated diffusion of protons into the mitochondrial matrix stops
A - Chemiosmosis B - ATP production C - Carbon fixation D - Hydrolysis of ATP Which processes occur in both respiration and photosynthesis?
A, B, D
Where is the tricuspid valve located
Between the right atrium and ventricle
DNA sequencing can be used for which of the following?
A - Treating cancer
B - Mapping disease genes in chromosomes
C - Determining the human genome
D - Studying how organisms are related
B, C ,D
