U3 Paper1A CSA HL

Which of these enables the flow of a continuous column of water up the xylem vessels towards the leaves of a plant?

Cohesion and tension within water in the xylem

Which bonds are responsible for the cohesive properties of water molecules?

Hydrogen bonds between water molecules

Which of the following aid in the transfer of water between cells in a leaf and the outside environment?

Capillary action in the cell walls

Why is water a polar molecule?

Because the electrons in the covalent bond are not shared equally

Which is the most accurate description of a nucleotide?

A monomer unit of nucleic acids.

Which of the following describes the backbone of DNA?

Covalent bonds between deoxyribose and phosphate molecules

The Miller–Urey experiment carried out in 1952 tested the hypothesis of the chemical origin of life. What were the key findings?

Complex organic molecules could form under simulated primordial conditions.

Which property of DNA explains how genetic information can be replicated accurately?

Complementary base pairing

HL What is a nucleosome?

DNA wrapped around histone proteins in a eukaryotic cell

What is a piece of evidence that all living organisms share a common ancestor?

DNA triplets code for the same amino acids.

Which codon would be found in RNA but not in DNA?

UCA

Which subunits would be connected by hydrogen bonds in a DNA molecule?

Cytosine to guanine

HL What is evidence for the endosymbiotic theory in eukaryotic cells?

Mitochondrion with DNA

Which property of water is not illustrated?

Adhesion

Which property of water allows the insect to walk on water?

Surface Tension

What explains these concentrations?

Active transport using a protein pump

What would happen to these cells if they were transferred to a hypertonic solution?

Cell membranes would detach from walls at some points.

What can be deduced from the graph?

At X, water has movedby osmosis into the red blood cells.