Yes Flashcards
Why do organisms require water
Transport
Good solvent
Type of bond found between amino acids in a protein
Peptide
Structural role of protein
Keratin hair
Reagent used to detect reducing sugar
Benedict’s solution
Role of a named mineral required by plants
Potassium
Protein synthesis
Name the group of biomolecules formed when a phosphate group replaces a fatty acid in a triglyceride.
Phospholipid
What is the importance of recycling elements such as nitrogen and carbon in an ecosystem?
It is important to recycle and continuously replenish nutrients into the environment for life to exist.
Name the processes that take place at A and B on the diagram above.
A-denitrification
B-death and decay
Legumes have a symbiotic relationship with nitrogen-fixing bacteria.
Explain the underlined term.
Relationship between 2 organisms of different species that live in close association to the benefit of both organisms
Name a type of bacteria, other than nitrogen-fixing bacteria, that play a role in the nitrogen cycle.
Nitrifying
The carbon cycle also occurs in nature.
State a biological similarity between the carbon cycle and the nitrogen cycle.
Both carbon and nitrogen cycle are types of biogeochemical cycles and tend to liberate elements from their cycles.
Name a human activity that is having a negative impact on the carbon cycle.
Burning fossil fuels
Cells can be classified into two main types: eukaryotic and prokaryotic.
Give two features of eukaryotic cells that distinguish them from prokaryotic cells.
Have a nucleus
Much larger
The cell membrane is described as being selectively permeable.
Explain the underlined term.
membrane that allows only some substances and molecules to pass into or leave the cell.
Suggest an advantage to a cell of having a selectively permeable membrane.
assists in the regulation of material movements in a cell.
Diffusion is a process by which molecules can move through cell membranes.
Explain the term diffusion.
the movement of individual molecules of a substance through a semipermeable barrier from an area of higher concentration to an area of lower concentration
Why can diffusion also be referred to as passive transport?
it does not require energy
Name one other process by which molecules can move through cell membranes
Osmosis
Variation
Individuals of a species have similar characteristics but they are rarely identical, the difference between them is called variation
Cause of variation
changes to chromosomes or genes (DNA)
Evolution
the process by which different kinds of living organism are believed to have developed from earlier forms during the history of the earth.
Briefly explain the role of natural selection in evolution.
Organisms that are more adapted to their environment are more likely to survive and pass on the genes that aided their success.
what is meant by the term species?
a group of organisms that can reproduce with one another in nature and produce fertile offspring
Causes of extinction
overhunting
Pollution
Draw a large labelled diagram of the human female reproductive system.
Your diagram should include at least six labels.
.
Following fertilisation, name the structure formed after the zygote divides by mitosis.
Embryo
Approximately 5 days after fertilisation, the structure referred to in 1 develops into a hollow ball of cells. What word describes this hollow of cells?
Blastocyst
What important structure develops from the outer layer of this ball of
trophoblast
As a human embryo develops, it organises into three primary germ layers.
From which germ layer do each of the following develop?
1. Skeleton and muscles
2. Lining of lungs and gut
3. Skin and nails.
- Mesoderm
- Endoderm
- Ectoderm
Give the precise location of each of the following in a flowering plant:
Production of pollen grains
Fertilisation.
Stamen
Ovary
Outline the role of meiosis and mitosis in the formation of pollen grains. hat is double fertilisation?
Meiosis-to produce four haploid microspores
Mitosis-The nucleus of each microspore then divides by mitosis to form a two-celled organism the pollen grain
What is double fertilisation
one female gamete unites with two male gametes
During fertilisation the pollen tube grows towards substances release from ovule. This is an example of what type of tropism?
Chemotropism
After fertilisation what does the ovary of flower become
A fruit
identify cell A, cell B and C in the above image of blood cells.
A-white blood cell
B-red blood cell
C-plasma