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
Why is blood a tissue
because it is a collection of similar specialized cells that serve particular functions
Name two substances, other than blood cells, oxygen and carbon dioxide, that are transported in the blood.
Nutrients and hormones
Where precisely in the human body are red blood cells produced?
Bone marrow
Blood disorder
Anemia
X and y vegetative propegatiin
X-tuber
Y-runner
From which part of the plant is structure X modified?
Roots
Name the structure formed when vegetative propagation takes place in a bud
Rhizome
Which part of a plant is modified to form a plantlet?
Propagated plants are genetically identical to each other and to the parent plant.
Give one advantage and one disadvantage of propagated plants being genetically identical to one another.
Advantage-maintaining the exact genetic characteristics of the parent plant.
Disadvantage-lack of genetic variation
Give two methods of artificial vegetative propagation and state one of its benefits.
Tissue culture-The plants can be grown throughout the year, irrespective of the season.
Cutting
Distinguish between the peripheral nervous system and the central nervous system.
The central nervous system is made up of the brain and spinal cord. The peripheral nervous system is made up of nerves that branch off from the spinal cord and extend to all parts of the body
Name a tissue that protects the central nervous system.
Meninges
What is the general name given to the nerve pathway shown in the diagram?
Spinal chord
Name the type of nerves labelled A, B and C. (iii) State two structural differences between A and C.
A-motor neuron
B-interneuron
C-sensory neuron
Sensory neurons have dendrites on both ends and are connected by a long axon that has a cell body in the middle. Motor neurons have a cell body on one end and dendrites on the other end, with a long axon in the middle.
How many synapses
3
What word is used to describe the chemicals which are released at a synapse?
Neurotransmitter
The spinal cord contains white matter and grey matter.
Give one other difference between them.
The tissue called “gray matter”, and is made up of cell bodies.
“White matter”, is composed of nerve fibers.
What is a hormone?
One of many substances made by glands in the body
Give one way in which a hormonal response differs from a nervous response
Nervous is faster
Outline the role of insulin in the human body.
regulate the body’s energy supply by balancing micronutrient levels
Where precisely in the human body is insulin produced?
Pancreas
Describe what happens if the body experiences an insulin deficiency
results in hyperglycaemia.
Describe how a negative feedback mechanism works in the animal horn onal
system
-Low levels of thyroxine cause the pituitary gland to produce TSH.
-This causes more thyroxine to be produced in the thyroid.
-If thyroxine levels are normal, TSH is not produced
What type of acids are dna and rna
Nucleic
What type of bases are thymine and cytosine
Pyrimidines
What type of chemical substances are ribose amd deoxyribose
Monosaccharides
A B C ear
A cochlea
B Eustachian tube
C ear drum
Function B D
B Pressure equalisation
D relay the vibrations of the incoming soundwaves produced by the eardrum to the incus.
Which two labelled parts of the ear are involved in generating nerve impulsps
A
E
(v) State a function of the ear besides hearing and name the part of the ear involved.
Balance
Semicircular canals
Name the part of the eye that has a similar function to the part labelled F
of the ear.
Optic nerve
Protect ear health
Turn volume down
The first stage in respiration does not involve oxygen, but it can take place whether oxygen is present or not.
1.
2.
What is the first stage of respiration called?
Glycolysis
Location glycolysis takes place
Cytoplasm
Name the intermediate 3-carbon compound formed at the end of the first stage.
Pyruvate
In second stage, which cell organelle does the 3-carbon intermediate compound move into?
Mitochondria
Compound that enters Krebs cycle
Acetyl Co a
3 products of krebs
2 co2
3 nadh
ATP or gtp
Fate of 2 products
CO2-waste gas
Nadh-The end result is loads of energy, approximately 34 ATP
True or false
T
F
T
F
T
T
F
Thymine
Cytosine
Type of bonding
Hydrogen
Prepare plant tissue for use
Chop up onion
Add salt to onion in a beaker
This clumps dna together
Why washing up liquid
Breaks down cell membrane and releases dna
Why was sodium chloride added
Clumps dna together
Why did u blend for min 3 seconds
Breaks down cell wall and releases dna
Blending for longer will damage dna
Why protease
Breaks down proteins that surround dna
Purpose of ethanol
Makes the dna precipitate out of solution
Appearance of isolated dna
White stringy
Aerobic and anaerobic
Aerobic means ‘with air’ and refers to the body producing energy with the use of oxygen
Anaerobic means ‘without air’ and refers to the body producing energy without oxygen.
Why stain cells
To clearly see cells
Name stain
Methylene blue
Presence of ethanol
Iodoform test
What result indicated presence
Yellow crystals
