QUESTIONS WITH CORRECT ANSWERS SOLVED.
Define community - CORRECT ANSWER✅✅The populations of different species living in a habitat
Define habitat - CORRECT ANSWER✅✅The place where an organism lives
Define population - CORRECT ANSWER✅✅All the organisms of one species living in a habitat
Define the lock and key theory process - CORRECT ANSWER✅✅The substrate enters the active site of
the enzyme and becomes an enzyme/substrate complex. The products then leave the active site
Describe how the heart works - CORRECT ANSWER✅✅Deoxygenated blood from your body returns to
the heart via the vena cava entering the right atrium. From here the blood flows through the atrium and
into the right ventricle. This then pumps blood into the pulmonary artery. This carries the deoxygenated
blood to the lungs. Here the blood's oxygen supply is replenished. The blood is now referred to as
oxygenated. The oxygenated blood flows back to the heart via the pulmonary veins entering the left
atrium. From here the blood flows through the valve and into the left ventricle. The left ventricle then
pumps blood into the aorta. This carries the oxygenated blood to the rest of the body.
Describe our double circulatory system - CORRECT ANSWER✅✅The right ventricle pumps
deoxygenated blood to the lungs to take in oxygen. The blood then returns to the heart.
The left ventricle pumps oxygenated blood around all other organs of the body. The blood gives up its
oxygen at the body cells and the deoxygenated blood returns to the heart to be pumped out to the
lungs again
Describe the digestion of bread - CORRECT ANSWER✅✅The digestion of bread starts with mechanical
digestion in the mouth. As you chew your food it gets broken down into smaller chunks so it has an
increased surface area which allows quicker digestion. Whilst the food is in your mouth, the salivary
amylase breaks down starch (long chains of simple sugar units bonded together) which is a catabolic
reaction. The enzyme is the salivary amylase and the substrate molecule is the starch which gets turned
into maltose. When you swallow the smaller pieces they pass through your oesophagus which squeezes
food from the mouth to the stomach. The stomach contains hydrochloric acid, which kills bacteria in
,food and provides the optimum pH for pepsin to work efficiently. No digestion of carbohydrates
happens here as the conditions aren't right for salivary amylase to work (pH7 is the best as it's neutral,
like in our mouth). The food then passes into the pancreas which produces pancreatic amylase and
breaks down the maltose into glucose. The glucose molecules are then absorbed through the small
intestine walls into the blood. Glucose is used in cellular respiration to provide the energy needed for
metabolic reactions within your cells.
Describe the features of a red blood cell - CORRECT ANSWER✅✅Biconcave disc for a larger surface area
to absorb oxygen
No nucleus - allows more room to carry oxygen
Describe the negative feedback system - CORRECT ANSWER✅✅Receptor detects a stimulus
The co-ordination centre receives and processes this information and coordinates a response
The effector produce a response that restores the optimum level
Describe the process of binary fission - CORRECT ANSWER✅✅The circular DNA and plasmid(s) replicate.
The cell gets bigger and the circular DNA strands move to opposite 'poles' of the cell. The cytoplasm
begins to divide and new cell walls begin to form. The cytoplasm divides and two daughter cells are
produced. Each daughter cell has one copy of the circular DNA, but can have a variable number of copies
of the plasmid(s).
Describe the process of mitosis - CORRECT ANSWER✅✅The chromosomes line up at the centre of the
cell and cell fibres pull them apart. The two arms of each chromosome go to opposite ends of the cell.
Membranes form around each of the sets of chromosomes. These become the nuclei of the two new
cells. Lastly, the cytoplasm and cell membrane divide. The cell has now produced two new daughter
cells, which contain the same DNA as the parent cell.
Describe the water cycle - CORRECT ANSWER✅✅Water evaporates from land, sea, and plants
As the water gets carried upwards, it cools and condenses to form clouds
Water falls from clouds as precipitation
It drains into the sea and the process starts again
Give a chemical defence of plants to prevent pathogens from affecting them - CORRECT
ANSWER✅✅Some produce antibacterial chemicals which kill bacteria
,Give a disadvantage of artificial hearts - CORRECT ANSWER✅✅Blood doesn't flow through artificial
hearts as smoothly, which can cause blood clots and lead to strokes. This means the patient has to take
drugs to thin their blood, which is a problem if they have an accident
Give a disadvantage of statins - CORRECT ANSWER✅✅They are a long-term drug that needs to be taken
regularly
Give a mechanical defence of plants to prevent pathogens/organisms from affecting them - CORRECT
ANSWER✅✅Some plants have thorns or hairs which stop animals from touching and eating them
Give a physical defence of plants to prevent pathogens from affecting them - CORRECT
ANSWER✅✅Waxy cuticle which provides a barrier
Give an advantage of artificial hearts - CORRECT ANSWER✅✅Less likely to be rejected by the patient's
body
Give an advantage of statins - CORRECT ANSWER✅✅Reduces the risk of strokes, coronary heart
disease, and heart attacks
Give an example of a behavioural adaptation of an organism - CORRECT ANSWER✅✅Migration
Give an example of a functional adaptation of an organism - CORRECT ANSWER✅✅Produce small
amounts of very concentrated urine
Give an example of a structural adaptation of an organism - CORRECT ANSWER✅✅Camouflage
Give five different examples of the antigenic material that could be used in vaccines - CORRECT
ANSWER✅✅Whole, live micro-organisms
A harmless or attenuated version
A dead pathogen
, A preparation of the antigens from a pathogen
A harmless toxin
Give five examples of plant tissues - CORRECT ANSWER✅✅Epidermal tissue
Palisade mesophyll tissue
Spongy mesophyll tissue
Xylem and phloem
Meristem tissue
Give five factors that affect food security - CORRECT ANSWER✅✅Increasing population
Demand for certain products increases
New pests and pathogens
Too expensive to maintain food production
Conflict
Give five uses for monoclonal antibodies - CORRECT ANSWER✅✅Pregnancy testing
Diagnosis of disease
Measuring and monitoring of medical conditions
Medical research
For treating disease
Give four adaptations of animals that live in deserts - CORRECT ANSWER✅✅Adaptations in the kidneys
to produce concentrated urine and need very little to drink
Being more active in the early morning and the evening since it is cooler
Relatively large surface area to volume ratios to keep them cool
Large, thin ears so the blood vessels are close to the surface, cooling them down
Give four consequences of global warming - CORRECT ANSWER✅✅Rising sea levels
Changes in species distribution