All Of Biology

know the diagram for the male reproductive system

know the diagram for the female reproductive system

Describe the role of the sperm duct

Sperm passes through the sperm duct to be mixed with fluids produced by the glands before being passed into the urethra for ejaculation

Describe the role of the urethra

The rube running down the centre of the penis that can carry urine or semen. A a ring of muscle in the urthra prevents them from mixing

Describe the role of Epididymis

A coiled tube, 6-7cm long, attached to the back of each testicle that transports concentrates stores and matures sperm cells

Describe the role of the testis

Contained in a bay of skin (scrotum) it produces sperm and testosterone

Describe the role of Scrotum

Sac supporting the testes outside of the body to ensure sperm are kept at a temp slightl lower than body temp

Describe the role of the penis

Passes urine out of the body from the bladder and allows semen to pass into the vagina during intercourse

Describe the role of seminal vesicle

Produces Semen

Describe the role of the oviducts

Connects the ovary to the uterus, lined with ciliated cells to push released ovum, where fertilization occurs

Describe the role of the ovaries

contains ova that mature and develop when hormones are released

Describe the role of the uterus

Hollow muscular organ with a vascular lining where a fertilized egg (zygote) implants to develop a fetus

Describe the role of the Cervix

Ring of muscle at the lower end of the uterus linking the uterus to the vagina

Describe the role of the vagina

Muscular tube leading to the inside of a womans' body, where male's penis enters and sperm are deposited during intercourse

Describe the 4 stages of fertilization

Gametes are produced

Male gametes are transferred to the female gamete egg cell

Fertilization occurs- sperm fuse with the egg

Zygote is formed-develops into a new individual

Describe how a sperm cell is adapted to its function

Have a flagellum for swimming

Lots of mitochondria for energy to swim

Acrosome containing enzymes to breakdown the outer layer of the egg

Describe how an egg cell is adapted to its function

Specialized outer layer- zona pellucida- when one of the sperm enters the egg the zona pellucida hardens the outer shell to not let any others in

Contains lots of mitochondria- for the sperm cell when it enters for energy

Can label an egg cell

Can label a sperm cell

Chromosomes for a Male and Female

Female XX

Male XY

Describe the role of the placenta in developing the embryo

Provides the embryo with nutrients and oxygen from the mothers blood which are essential for growth and development

Allows waste products from the embryo's blood to be removed

What goes from the mothers blood to the fetus

Oxygen

Nutrients

What goes from the fetus to the mother

Carbon dioxide

Urea

Why is the placenta efficient/adapted to its function

Large SA

Thin wall for efficient diffusion

Acts as a barrier to some toxins and athogens

How long is the average menstrual cycle

28 days

What are the 4 cycles in mensturation

Menstruation:Breakdown and shedding of the uterine lining

Follicular phase: The endometrium builds up and an egg matures in the ovary

Ovulation: The release of a mature egg from the ovary (usually day 14

Luteal phase: The uterus props for a ferilised egg, if no fertilization occurs the lining breaks down and the cycle repeats

Timings of Oestrogen and where it is released from

Released from the ovaries

RIse from d1- peak just before d14

The peak in oeastrogen occurs just before the egg is released

And stimulates the pituitary gland to release LHStimulates the uterus to replace the endometrium

Describe the role of Oestrogen in the menstrual cycle

stimulates the pituitary gland to release LH

Stimulates the uterus to replace the endometrium

Describe the role of progesterone in the menstrual cycle

Inhibits FSH and LH production

If fertilization does not occur- the fall in progesterone levels causes the uterine lining to break down (menstruation)

Timings of Progesterone and where it is released

Starts to rise on d14 and stays moderatly high until d 25 starts dipping

Describe the role of LH in the menstrual cycle

Causes ovulation to occur and stimulates the ovary to produce progesterone

Results in the formation of Corpus Luteum

Timings of LH and where it is released

Released from the pituitary gland

Released when oestrogen levels have peaked

peaks d14

Describe the role of FSH in the menstrual cycle

Responsible for egg maturation in the follicles of the ovary

Stimulates the follicles in the ovaries to secrete oestrogen after the egg has been released

How does the amniotic fluid protect the embryo/fetus

Protects it against sudden movements, and also provides a medium for the fetus to move in

Role and effects of oestrogen secondary characteristics

breast growth, widening of the hips, growth of pubic/underarm hair, and the start of the menstrual cycle.

Role and effects of testosterone secondary characteristics

deepening of the voice, increased muscle mass, broadening of shoulders, growth of facial/body hair, and the start of sperm production.

What Charactersistics must a organism follow to be classified as living

Movement

Respiration

Sensitivity

Control (their internal conditions)

Growth

Reproduction

Excrete

Nutrition (require it)

What is a eukaryotic cell?

A cell with a nucleus

What is a prokaryotic cell

A cell without a nucleus

Describe common features shown by plants

Multicellular, chloroplasts, cellulose cell walls, they store carbs as starch or sucrose. .

FLowering plants, maize

Describe common features of animals

Multicellular organisms

Theri cells do not contain chloroplasts

No cell walls

Often have nervous coordination

Oten store carbs as gylocegen

Examples: mammals (humans) insets (mosquito)

Deescribre common features of Fungi

No able to carry out photosynthesis

Body is usually orgainsed into mycelium made from threal like structures called hyphae which contain many nuclei

Some are single-celled

Have cell wals made of chitin

They feed by sparotrophic nutrition

May store carbs as gylcogen

Examples: Mucor, yeast

What is saprotrophic nutrition?

Extracellular secretion of digestive enzymes onto food material and absorption of the organic products

Define the term autotroph.

An autotroph is an organism that can produce its own food for energy.

What is the primary photosynthetic pigment in photosynthesis?

Chlorophyll

Do plants have an organ system

Yes, shoot system contains stem, leaves, flowers

Define the term organelle.

Organelles are structures within cells that carry out particular functions, e.g. the nucleus.

List the levels of organisation in complex multicellular organisms.

The levels of organisation should be listed in the following order:

Organelles

Cells

Tissues

Organs

(Organ) systems

Name three biological molecules present in living organisms.

Biological molecules present in living organisms include:

carbohydrates

proteins

lipids

What are carbohydrates?

Carbohydrates are molecules that contain the elements carbon, hydrogen, and oxygen.

What are the chemical elements present in proteins?

All contain carbon, oxygen, hydrogen and nitrogen.

Some Sulfur

From which smaller molecules are lipids built?

Lipids are fats and oils made up of fatty acids and glycerol.

What are the chemical elements present in lipids?

Lipids are made of carbon, oxygen and hydrogen.

Define the term monosaccharide.

A monosaccharide is a simple sugar like glucose or fructose.

Define the term disaccharide.

A disaccharide is formed when two monosaccharides join together.

Describe the common features of Protoctists

Microsocpic single-celled organisms.

Some like Amoeba live in pond water have features like animal cells

Others like Chlorella have chloroplasts and are more like plants

A pathogenic example is Plasmodium, causing malaria

Describe common features of bacteria

Microscopic single-celled organisms

Thery have a cell wall, cell membrane, cytoplasm and plasmids

Don't have nucleus but have a circular chromosome of DNA

Some bacteria can carry out photosynthesis but most feed off other living or dead organsims

Example Pneumococcus, pathogen causing pneumonia

What is a pathogen

Disease causing organism

Describe the common features of viruses

They are NOT living

Ther are smaller than bacteria

Parasitic and can only reproduce inside living cells

They infect every type of living organism

Wide variety of shapes and sizes

No cellular structure but have a protien coat and contail one type of nucleic acide either DNA or RNA

Examples: Tobacco mosaic virus causing the discolouring of the leaves by tobacco plants

The influenza birus, cuases the flu

HIV virus, causes AIDS

What is the food test for Protein

Biuret test - blue to purple

What is the food test for Reducing Sugars

Benedict's test- blue to red, orange, yellow based on strength

What is the food test for starch

Iodine test

Yellow-Blue/black

What is the food test for fats

Ethanol- Cloudy emulsion formed

What is an enzyme?

A biological catalyst that speeds up the rate of the reaction without being used up in that reaction

Describe how the increase or decrease in temp can affect the enzyme function

As temperature increases towards this optimum, particles have more kinetic energy, so enzyme and substrate collide more often, so the rate of reaction increases.

Above the optimum, extra heat starts to break bonds that hold the enzyme's active site in its specific shape.

This changes the shape of the active site, so the substrate no longer fits; the enzyme is denatured and the reaction rate falls sharply. NO LONGER COMPLEMENTARY

At very low temperatures, enzymes are not denatured, but they work slowly because there is little kinetic energy, so few collisions.

Describe a practical to investigate how enztme activity can be affected by changes in temperature

C (Change) - Temperature of the reaction mixture (e.g. 10,20,30,40,50.60.70.80)

O (Organism) - The same enzyme source: amylase from the same type and concentration each time.

R (Repeat) - Repeat each temperature at least 3 times and calculate a mean time for starch breakdown.

M (Measure) - Measure the time taken for iodine to stop turning blue‑black (time for all starch to be digested).

S (Same) - Keep these the same:

same volume of amylase and starch

same concentration of amylase and starch

same pH (e.g. with a buffer)

how can enzyme activity be affected by changes in pH

If pH moves away from the optimum (either more acidic or more alkaline), it can change the charges on amino acids in the enzyme.

This disrupts the bonds that hold the enzyme's active site in its specific shape.

If the pH is very different from the optimum, the enzyme can become denatured, meaning its shape is permanently changed and it no longer functions. No longer Complementary

Describe a practical to affect how enzyme activity can be affected by changes in pH

C (Change) - pH of the reaction mixture (e.g. pH 4, 6, 7, 8, 9) using different buffer solutions.

O (Organism) - Same enzyme source: amylase of the same type and concentration each time.

R (Repeat) - Repeat each pH at least 3 times and calculate a mean time for starch breakdown.

M (Measure) - Measure the time taken for iodine to stop turning blue‑black (time for all starch to be digested).

S (Same) - Keep these the same:

same temperature (e.g. same water bath)

same volume of amylase, starch, and buffer

same concentration of amylase and starch

What is diffusion

The movement of particles from an area of high concentration to an area of low concentration down a concentration gradient

What is osmosis

The net movement of free water molecules from an area of high WP to an area of low WP through a partially permeable membrane

What is active transport

the movement of particles from an area of lower concentration to an area of higher concentration, against the concentration gradient, which requires energy

Describe factors that can affect the rate of movement of substances in and out of cells

Surface area : volume ratio Cells or organisms with a larger SA:VOL have more membrane surface for substances to cross per unit volume, so substances move in and out faster.

Distance The shorter the distance for diffusion (e.g. thin alveolar walls), the faster substances move. A thicker barrier slows the rate.

Temperature Higher temperature gives particles more kinetic energy, so they move and collide more, increasing the rate of diffusion (and speeding enzyme‑controlled active transport).

Concentration gradient A steeper concentration gradient (big difference in concentration between two sides) causes a faster net movement of particles; as the gradient becomes less steep, the rate slows.

Describe an experiment to investigate the rate of diffusion in non-living substances

Make agar jelly cubes containing a coloured pH indicator.

Place cubes in acid and observe how fast the colour changes from the outside in.

Smaller cubes (higher SA:VOL) change colour faster, showing faster diffusion.

Describe an experiment to investigate the rate of osmosis in living substances

Living (potato in different concentrations):

Cut equal‑sized potato cylinders and place them in different concentrations of sugar or salt solution.

Leave for a set time, then dry and weigh them.

Mass increases in dilute solution (water moves in), and decreases in concentrated solution (water moves out) by osmosis.

CHemical and word equation for aerobic respiration

glucose+oxygen→carbon dioxide+water+ (energy 38ATP)

C6H12O6+6O2→6CO2+6H2O+38ATP

Chemical and word equation for anaerobic respiration

Word equation: glucose→lactic acid

Symbol equation: C6H12O6→2C3H6O3+2ATP

Chemical and word equation for anaerobic respiration in yeast

Word equation: glucose→ethanol+carbon dioxide

Symbol equation:C6H12O6→2C2H5OH+2CO2

How does respiration produce ATP

The release of energy from glucose which is used to make ATP

What does ATP provide

Energy for cells

Investigate the evoluation of CO2 from respiring seeds

Investigating CO2 evolution (germinating vs boiled seeds):

Set up two flasks or test tubes:

A: germinating seeds (soaked and starting to grow)

B: boiled / dead seeds or glass beads (control)

Add hydrogencarbonate indicator (or limewater) to each:

Hydrogencarbonate turns yellow if CO22 increases.

Plug with cotton wool and leave in a warm place.

Compare colour change: germinating seeds release CO22 by respiration; the control should show little or no change.

Investigate the evoluation of heat in seeds

Investigating heat evolution:

Put germinating seeds in a thermos flask with a thermometer; set up another identical flask with boiled seeds or beads as a control.

Fit a lid with holes for the thermometers.

Record the temperature in both flasks over time.

The flask with germinating seeds will show a greater temperature rise, showing that respiration releases heat.

Describe gas exchange in the lungs

In the lungs:

Air in the alveoli has a high concentration of oxygen, blood arriving has low oxygen.

Oxygen diffuses from alveoli into blood down its concentration gradient.

Blood arriving has high carbon dioxide, alveoli air has lower CO2, so CO2 diffuses from blood into alveoli to be exhaled.

Can label a diagram for lungs ribs ect

Describe how the intercostal muscles and the diaphragm change during inhalation

The external intercostal muscles contract, pulling the ribs upwards and outwards.

The diaphragm contracts, moving downwards and becoming flatter.

This increases the volume of the thorax, so pressure inside the lungs decreases, and air moves into the lungs.

Describe how the intercostal muscles and the diaphragm change during exhalation

The external intercostal muscles contract, pulling the ribs upwards and outwards.

The diaphragm contracts, moving downwards and becoming flatter.

This increases the volume of the thorax, so pressure inside the lungs decreases, and air moves into the lungs.

How are alveoli best adapted for gas exchange

They have a very large surface area (millions of tiny sacs) so more gas can diffuse at once.

Their walls are extremely thin (one cell thick), giving a short diffusion distance.

They have a good blood supply from a dense network of capillaries, keeping the concentration gradient steep for O2 and CO2

The alveoli are moist, so gases dissolve, making diffusion easier.

Describe th econsequences of smoking on the lungs

Tar damages cilia in the airways so mucus is not cleared; this leads to bronchitis and more infections.

Tar also damages alveolar walls, reducing their surface area and elasticity, causing emphysema - gas exchange becomes less efficient, so the person gets breathless.

Carcinogens in cigarette smoke can cause lung cancer.

Describe th econsequences of smoking on the circulatory system

Nicotine increases heart rate and blood pressure, putting extra strain on the heart.

Carbon monoxide binds to haemoglobin, reducing the blood's ability to carry oxygen.

Chemicals in smoke damage the lining of arteries, leading to atherosclerosis (fatty deposits), which can cause coronary heart disease and heart attacks.

What is Coronary Heart Disease

Coronary heart disease (CHD) is when the coronary arteries (the arteries that supply the heart muscle with blood) become narrowed or blocked by fatty deposits (atheroma) in their walls.

This means:

Less oxygen and glucose reach the heart muscle.

The heart muscle cannot respire aerobically properly, so it gets less energy.

If a coronary artery becomes completely blocked, part of the heart muscle dies, causing a heart attack.

Describe a pracrical to investigate the effect of exercise on the release of CO2 and breathign rate

C (Change) - Amount/intensity of exercise (e.g. time spent stepping, or no exercise vs exercise).

O (Organism) - The same person (or same age group) for all repeats.

R (Repeat) - Repeat the exercise at least 3 times and calculate a mean breathing rate/CO2 result.

M (Measure) -

Count breaths per minute before and after exercise.

Observe change in limewater (more/cloudier means more CO22) or colour change in hydrogencarbonate indicator.

S (Same) - Keep these the same:

same duration and type of exercise (e.g. 2 minutes of step‑ups at same speed)

same person (if possible)

same time of day and similar temperature

What should a balanced diet include

Appropriate portions of carbs, protein, lipids, vitamins and minerals, water and fibre

What is the funcion and possible sources of carbohydrates

Function: main source of energy for respiration.

Sources: bread, rice, pasta, potatoes

What is the funcion and possible sources of

Function: growth and repair of tissues; making enzymes and hormones.

Sources: meat, fish, eggs, dairy, beans, lentils, nuts.

What is the funcion and possible sources of

Function: energy store, insulation, protection of organs, making cell membranes.

Sources: butter, oils, nuts, seeds, oily fish.

What is the funcion and possible sources of vitamin A

Function: good vision (especially in dim light), healthy skin and immune system.

Sources: liver, dairy, oily fish, carrots, leafy vegetables.

What is the funcion and possible sources of Vitamin C

Function: making collagen, helps wound healing, keeps skin and gums healthy, prevents scurvy.

Sources: citrus fruits, berries, peppers, tomatoes, green vegetables.

What is the funcion and possible sources of Vitamin D

Function: helps absorb calcium; needed for strong bones and teeth.

Sources: sunlight on skin, oily fish, eggs, fortified foods, dairy.

What is the funcion and possible sources of Calcium

Function: strong bones and teeth, blood clotting, muscle function.

Sources: milk, cheese, yoghurt, leafy green vegetables.

What is the funcion and possible sources of iron

Function: needed to make haemoglobin in red blood cells (carries oxygen).

Sources: red meat, liver, beans, spinach, fortified cereals.

What is the funcion and possible sources of water

Function: main part of blood and cytoplasm, transport, temperature control, dissolves substances, needed for reactions.

Sources: drinks, fruits, vegetables, soups.