5th year biology

science

the organized study of the physical material and living world

biology

the study of living things

the scientific method

a process of investigation in which problems are identified and their suggested explanations are tested by carrying out experiments

step 1 of the scientific method

observation

step 2 of the scientific method

hypothesis

step 3 of the scientific method

experimentations

step 4 of the scientific method

collection and interpretation of data

step 5 of the scientific method

conclusion

step 6 of the scientific method

relating the conclusion to existing knowledge

step 7 of the scientific method

reporting and publishing the results

observationhy

when something is noticed they may be directly obtained by our senses or indirectly by the use of microscopes or thermometers

hypothesis

an educated guess based on obsrvation

experiement

an experiment is designed to test a hypothesis

what should the results of the experiment do

it will either support or contradict the hypothesis

what happens in step 4 collection and interpration of data

the information that is obtained in the course of experiments is collected recorded and analysed

conclusion

a summary of the results of an experiment

data

it consists of the measurements observations or information gathered from experiments

what should happen in step 6

the hypothesis is supported if the results agree fully

why should the results of an experiment be reported

so they can be examined and analyzed by others in this way new ideas are made available to all scientists

why are experiments published

in order to allow them to be repeated

theory

a theory is a hypothesis supported by many different experiments

principle or law

a principle or law arises from a theory that has been show to be valid when fully tested over a long period of time

experiment second definition

a test for a hypothesis

variable

a factor that may change in an experiment

what is the funtion of a control

to act as a comparison for the the experiment or the results

give some limitations of the scientific method

extent of knowledge ,human error ,accidental discovery, bias and ability to interpret results

what is a control

a control is used as a comparison against which the actual experiment can be judged

why is random selection important

to avoid bias and to increase reliability

what regent or chemical did you use to detect the preccesence of protein

copper sulfate

give reason on why you chopped up the plant tissue in the microscope experiment

to break the cell wall and to allow the cyptoplasm to leak out

what is the purpose for carrying out an experiment

to test the hypothesis

double blind testing

neither the tester nor the subject know who gets the drug (or who gets the placebo)

why is it important to publish research

so that others can repeats the experiment and so that information is made available to all

how can scientists avoid bias

large sample size ,replicates or double blind testing

what is the the purpose of replicated

to ensure reliability ,to avoid bias or to verify a result

what is the purpose of a hypothesis

to form a basis of prediction

what is a replicate

a repeat or copy of an experiment

how do you expose the semilunar valve when dissecting a sheep heart

cut open the aorta or cut open the pulmonary vein

what are the principles of experimentation

careful planning , ensure the experiment is safe , design a control experiment , ensure experiments must be fair

ethics

ethics relate to ether issues are right or wrong

why should a large sample be tested in an experiment

a large sample produces more reliable results

why should experiments be easy to replicate

results can be show be shown to always be true and not caused by an unknown influence

organism

an organism is a living thing

metabolism

the sum of all chemical reactions in an organism

continuity of life

this means that all living things arise from other living things of the same type

microscopic organisms

single celled amoeba and bacteria

what are metabolic reactions controlled by

they are controlled by chemical called enzymes

describe an animal with high metabolic rate

they are fast acting

what reactions does metabolism include

growth movement and respiration

life

life is defined as the possession of all the following characteristics organised , requiring nutrition and excretion and capable or responding and reproducing

organisation

means that living things are composed of cells tissues organs and organ systems

nutrition

the way in organisms obtain food

what are the basic organisational features of life

cells

explain the order for organisation

cells to tissue to to organs to organ system to organism

tissue

groups of cells that preform similar function

excretion

the removal of waste products of metabolism from the body

response

the way in which all living things reacts to changes in their surroundings

explain the balance excretion helps provide

in order to survive organisms must maintain a fairly constant balance between their inside and outside environments

why is it important to excrete

many processes produce poisonous waste they could damage the organism if they accumulate

why do plants have less need for excretion

they make their own food and do not produce or take in as much waste

how do plants excrete wastes

they excrete waste gases through openings called stomata on the underside of their leaves

what does the liver do in excretion

it breaks down toxic material

explain excretion in an animal

animals transfer waste internally from their cells to the blood the liver breaks down the toxic material and the blood carries the waste through the excretory system

name excretory structures in humans

skin lungs and the urinary system

explain stimuli

living things have to respond in order to react to changes or stimuli in their internal and external environments

reproduction

the production of new individuals

sexual reproduction

the union of sex cells

asexual reproduction

does not involve the union of se cells

nutrition

the way in which organisms obtain and use food

what are nutrients

chemical substances present in food

what are nutrients important for

a source of energy to make chemicals needed for metabolic reaction and as the raw materials for the growth and repair of structures in the organism

identify one difference between fats and oils at room temperature

fats are solid and oils are liquid

indentify the diffference between triglycerides and a phospholipid

triglycerides have three fatty acids and have no phosphate whereas phospholipids have two fatty acids and have a phosphate

identify one metabolic role for lipids in cells

energy source or store energy

name one fat soluble vitamin in the diet

D

name one defficieny dissorder of the fat soluble vitamin

ricket(osteomalacia)

name 5 elements in dissolved salts

sodium chlorine potassium calcium and magnesium

name the three elements found in lipids

carbon hydrogen and oxygen

what is the basic unit that makes up lipids

three fatty acids joined to a glycerol

name a storage polysaccharide found in animals

glycogen

what is the ratio of hydrogen atom to oxygen atom in a carbohydrate

2 : 1

what is a structural role of lipids

lipids are responsible for contributing to membrane tension, rigidity, and overall shape they also allow for insulation

what is the man structualaral polysacharide found in plants

cellulose

what is a triglyceride composed of

glycerol and three fatty acids

name 2 proteins with a fibrous structures

collagen and keratin

what nutrient is identified by benedicts ltion or fehlings

a reducing sugar

what are the six most common elements found in food

carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur.

what element make 99% of the mass of atoms present in living organisms

carbon hydrogen oxygen and nitrogen

what are compounds made from “carbon” reffered to as

organic compounds

biomolecules

chemicals that are made inside a living thing

what are biomolecules that contain carbon referred to as

biochemicals

what are the 4 major types of biomolecules

carbohydrates lipids proteins and vitamins

write the chemical formula or glucose

C6 H12 O6

explain monosacharide

they are carbohydrates composed of a single sugar unit they are the simplest and smallest types of carbohydrates

single sygar unit

a ring of carbon atoms

give two monosacharides

glucose an fructose

explain glucose

its made in plants during photosynthesis and is the main molecule from which living things get their energy it is found in sweets

fructose

it has the same formula as glucose but is common if fruits and is much sweeter than glucose

dissacharides

they are composed of two sugar units composed together they are sweet and soluble in water

give two examples of dissacharides

glucose and fructose