JC study

Reproduction

The production of new individuals. Sexual reproduction involves two parents.

Puberty

The age of sexual maturity.

Gametes

Sex cells: The male gamete is the sperm, and the female gamete is the egg.

Testes

Produce sperm in the male reproductive system.

Scrotum

A sac which holds the two testes and allows the testes to be slightly cooler than the body temperature.

Sperm ducts

Carry the sperm from the testes to the penis and are attached to a number of glands which produce a liquid called seminal fluid.

Penis

Contains the urethra, through which sperm can pass.

Ovaries

Produce eggs in the female reproductive system.

Fallopian tubes

Collect the egg as it is released from the ovary, transport the egg towards the uterus, and are the location where sperm and eggs may join.

Uterus (or womb)

The location where the embryo or baby develops during pregnancy.

Cervix

The opening into the uterus (through which sperm can enter).

Vagina

A muscular tube into which the penis releases sperm and forms the birth canal when a baby is born.

Menstrual cycle

A series of events that occur in the female (roughly) every 28 days, starts at puberty, stops at the menopause, and stops happening if the female is pregnant.

Menstruation or having a period

The lining of the uterus (which contains a lot of blood) breaks down and passes out of the vagina (Days 1-5 of the menstrual cycle).

Ovulation

The egg is released from the ovary (Day 14 of the menstrual cycle).

Fertile period

The time during the menstrual cycle when pregnancy is most likely.

Sexual intercourse

The act of sexual union (i.e. the placing of the penis in the vagina), also called copulation, causes sperm to be released into the vagina.

Fertilisation

The joining of the nucleus of the sperm with the nucleus of the egg that forms a single cell called a zygote.

Zygote

A single cell formed by the joining of the nucleus of the sperm with the nucleus of the egg during fertilisation.

Implantation

The ball of cells attaches to the lining of the uterus

Embryo

The ball of cells attached to the lining of the uterus develops into the embryo.

Foetus

At 8 weeks the embryo looks like a human and is called the foetus.

Placenta

Forms soon after implantation, attaches to the lining of the uterus, and contains blood vessels which pass to and from the embryo/foetus.

Umbilical cord

Blood vessels pass through the umbilical cord.

Labour

The muscles in the wall of the uterus begin to contract at the time of the birth

Afterbirth

Contractions of the uterus force the placenta and umbilical cord out of the uterus.

Contraception

The deliberate use of artificial methods to prevent pregnancy.

IVF (In Vitro Fertilisation)

Involves taking sperm and eggs from the parents and allowing them to join outside the body; one (or more) of the embryos is placed back in the uterus of the female.

Stem cells

Cells that can develop into any type of body structure.

ingestion

the taking of food into the ailimentary canal

absorbtion

the taking of the soluable foo particles into the bloodstream to be taken all around the body

digestion

the physical and chemical breakdown of food to make it soluable

egestion

the removal of undigested food from the ailimentary canal

ways of producting electricity

• fossil fuels

• nuclear fuels

• wind

• moving water

• solar

• geothermal

how fossil fuels create electricity

coal, oil and gas are sources of chemical energy.

this heat energy is released when you burn them.

The heat energy released boils water and makes steam

The moving steam has kinetic energy which turns the blades on a turbine

The turbine spins a generator which creates electricity

What’s the problem with burning fossil fuels?

Results in huge amounts of greenhouse gasses being released into the atmosphere. This drives climate change which in turn causes climate change

Why should we care

The main three drivers of the release of greenhouse gases are:

Electricity production

Transport

Agriculture

sustainability

meeting the needs of the present, without compromising te ability of future generations to meet their own needs

nuclear fuels

a substance that facilitates the making and breaking of nuclear bonds to create energy

pros of nuclear fuels

efficient method of producing large quantites of electricity for small quantites of nuclear fuel. No carbon emmissions

cons of nuclear fuels

nuclear waste is hard to dispose of and poses a health risk. the risk of a nuclear meltdown of explosion are everpresesnt.

electrical power

the amount of electrical energy transformed to other forms in a second, measured in Watts

electrical power triangle

power over voltage times current

kilowatt-hour

the amount of energy provided when one Kilowatt of energy is used for one hour

electricty

flow of electrical power or charge

conventinal current

positive charges move from the positive terminal of the battery to the negative terminal.

actual current

negative charges move form the negative terminal of a battery to the positive terminal.

current

the movement of electron carrying charge is called current. when we look at current we are looking at the movemenr of electrical charge.

measuring current

measured in ampheres (A), often shortened to amps, mesured using a ammeter

potential difference/voltage

the ability for electrons to move between positive and negative terminals.

basically its a measure of how much work a flow of electrons can do

measuring voltage

measured in voltage (V) using a voltmeter.

difference between voltage and current

current is the number of electrons flowing along a wire

voltage is the ability of of the electrons to do a specific task

resistance

the opposition to the flow of electrons.

measuring resistace

is measure in Ohms using an ohmmeter

in a circuit an ammeter must be…..

in series

in a circuit, a voltmeter must be….

in parallell

calculating current, voltage and resistance

use a triangle with V on top and I and R in the bottom

Health

A state of complete physical mental and social wellbeing.

Health includes physical health(dealing with the body) and mental heath( dealing with the mind)

Factors affecting health

Human health is affected by interacting with the following

-inherited factors

-environmental factors

-personal behaviour

Microorganisms

Small living things. Only visible with a microscope and are found everywhere. Consists of virus’s fungus and bacteria

Pathogens

Microorganisms that cause disease

Parasites

Living things that get their energy from other living things and usually cause harm

Bacteria

Microorganisms made of a single cell. Cause disease and decay and may be used to produce useful substances. They are larger than viruses. Bacterial diseases include lockjaw and cholera

Fungi

Simple non green organisms may be single celled( yeast) or made to many cells. May cause disease or decay and some are edible (mushrooms). Larger than bacteria. Causes ringworm and athlete’s foot

Virus’s

Smallest living things. Cause diseases such as measles, AIDs, Covid 19

Antibiotics

Chemicals made by fungi or bacteria that kill or prevent the growth of bacteria

Immunisation

The process of being made immune (or resistant) to a disease, usually after exposure to the disease

Vaccination

The introduction of a small, non-reproductive, dose of a disease into the body to stimulate and produce antibodies

Antibodies

Proteins produced by white blood cells to destroy microorganisms that have entered the body

Gene disorders

inherited factors are controlled by genes. Single cell gene disorders include sickle cell and coeliac disease. Multi cell gene disorders include cancer and Alzheimer’s.

Cancer

The term given to a range of conditions(~200) in which cells lose control of how fast they divide and for how long they divide. This causes the uncontrolled rapid growth of cells. Cancer usually requires a number of genes to change. Some people are born with one or more of there alterations already in place. These people are more likely to get cancer

Factors speeding up risk of alterations in genes

Ultraviolet radiation

Smoking

Viruses

Lifestyle

The main lifestyle choices effecting someone’s health are diet smoking exercise drink/drugs sleep and work life balance

Diet

A balanced diet contains the correct amount of carbohydrates, protein, fats, vitamins, minerals and water

Energy values

Different foods have different energy values. Carbs and proteins have the same energy values. Fats have twice the energy value of protein. Our body does not normally use protein for energy

Risks of over eating

Overweight, breathing issues

Risks of undereating

Depression, weak bones

Risks of smoking

Smoking is bad for the lungs as it

Increases risk of heart attacks

Increases risk of lung ( and other) cancers

Exercise

Exercise is good for our health as it:

Increases energy levels (improves workings of our body parts)

Improves our mood (by stimulating brain chemicals)

Sleep

Improves our concentration

Increase energy levels

Young people need more sleep than old people

Young people need 8 hrs sleep

Work life balance

We must allow time for relaxation and player should be aware of what makes us happy and allow time for this each day

Risks of alcohol

It’s toxic ( makes us feel sick and lose coordination)

It changes our mood

Drugs

Drugs cause different effects depending on

Type of drug

Amount taken

Size of person

Benefits of microorganisms

Decomposers

produce antibiotics which are chemicals made by bacteria and fungi to kill or prevent the reproduction of other bacteria. Penicillin is an example of an antibiotic

We can reduce the risk of infection if we

Wash our hands with soap and warm water frequently

Cook food properly (high temperatures kills most microorganisms)

Motion

Motion or movement is happening every day around us. There are different et types of motion. For example when you pluck a guitar string it vibrates or a DVD spins in a circular manner

Scientific unit of speed

Unit of distance Meter

______________ + ________

Unit of time. Second

You may write this as ms-1 or m/s

Speed

The distance travelled by an object in one unit of time

Calculating speed

Speed =distance over time

Time = distance over speed

Distance = time x speed

Always remember to have the distance value in meters and the time value in seconds

Velocity

The speed of a body and the direction it’s moving

Acceleration

The change in speed divided by the time taken for the change ( or the rate of change in velocity)

Acceleration calculation

Final speed - first speed. —————————————— Time taken for the change

Units of acceleration

M/s2 or ms-2

photosythesis

the process in which plats can make their own foodword

word equation of photosynthesis

carbon dioxide + water with light and energy → glucose + oxygen

requirements of photosynthesis

water from the soil

carbon dioxide from the air

chlorophyll

chlorophyll

the green pigment found in the chloroplast of leaves. it traps energy that is needed to make the glucose

leaf adaptations for photosynthesis

1. flat and thin-to absorb maximum light

2. leaves have tiny pores called stomata- to allow CO2 in and O2 out

3. leaves have chloroplasts- these contain chlorophyll

Products of photosynthesis

Glucose-used in respiration. Stored as starch

Oxygen- used in respiration. Released into the air and animals then use it for respiration