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Flashcards in Biology Deck (14)
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1
Q

Give the definition and examples of continuous and discontinuous variation.

A

Discontinuous variation is traits that can be classified as types e.g. Attached Or Detached Earlobes. Continuous variation is traits that can’t be grouped such as height and foot length.

2
Q

Contributions of both environmental factors and genetics to the appearance of an organism (phenotype)

A

An organisms genes decide how tall it can grow but the environment around it can also change whether it reaches its full potential or not.

3
Q

Describe the causes and effects of Coronary Heart Disease.

A

Causes: Lack of Exercise, stress, smoking, high alcohol consumption, high blood pressure and being overweight.

Effect: The small arteries that supply blood to your heart get blocked by fat deposits and disrupt the smooth flow of blood and cause major tissue damage.

4
Q

Effects of Smoking

A

Narrows the artery lumens - Cholesterol build up resulting in coronary heart disease, narrowing of air way resulting in bronchitis, hot ash paralyses cilia and scars alveoli (emphysema), tar resulting in lung cancer.

5
Q

Function of Cilia and Mucus in the Trachea.

A

Dust and Microbes in the air we breathe are trapped by mucus in the airways. In healthy airways, Cilia sweep mucus and its trapped debris up to the throat where it is swallowed.

6
Q

How are plants leaves Structure very efficient?

A

It’s leaves are large and flat and at right angles to the direction of sunlight. This is a perfect position for catching as much light as possible. Also it’s leaves are arranged so that they do not overlap and shade each other. In shady places, plants grow larger leaves to capture the same amount of light. Leaves are also very thin, so that gases can pass in quickly from the air to the cells.

7
Q

Describe a plants leaf structure.

A

The top layer of cells, the epidermis, is transparent. It has a waxy waterproof layer over it that stops the leaf from drying out. Light passes through the epidermis to the next layer of cells, the palisade layer. Inside the leaf, most cells are green. They contain green chloroplasts where food is made. Palisade cells are specialised for photosynthesis. They are provided with water by the veins in a leaf. Below the palisade layer is a layer called the Spongy Mesophyll. In this layer the air spaces act as reservoirs for the gases that palisade cells need. There is another layer of epidermis on the lower surface of the leaf. This is waterproof too. Gases such as Carbon Dioxide enter and leave through tiny pores called Stomata. Guard Cells by each Stoma shut the Stomata at night. Water is also needed for photosynthesis.

8
Q

Word Equation for Photosynthesis.

A

Carbon Dioxide + Water = Glucose + Oxygen

9
Q

Uses of Minerals in Plants.

A

Minerals are used to make new materials from Glucose, such as protein. Plants grow poorly in soil with few minerals.

10
Q

Describe the uses of Glucose in plants.

A

Plants use Glucose from photosynthesis to make the materials they need to grow. Some of the glucose made by a plant is used in respiration. The rest is used to make new materials or is stored in the plant. Plants make protein from glucose and from the minerals they absorb. They also make cellulose for their cell walls, oil and starch. Plants make cells in roots, shoots and flowers using these new materials. Starch is stored in roots and seeds. Peas and some other seeds are stores of protein, while peanuts are stores of oil. Fruits are often full of sugar or oil to attract animals that disperse the seeds inside.

11
Q

How do you complete random sampling and why is it random?

A

You can make a sample random by throwing the quadrat with your eyes closed in different areas and it must be random or else it will be bias.

12
Q

How do you use a quadrat?

A

A tool called a quadrat is often used in sampling plants. It marks off an exact area so that the plants in that area can be identified and counted.

13
Q

How do you estimate plant species coverage in a quadrat sample?

A

You simply take your hand which represents 4% coverage in junior Year and 5% in Senior Year, then use it to estimate the percentage of plant coverage and non-living environment.

14
Q

What is an Allele?

A

An Allele is a discontinuous body feature which can either be dominant or recessive.