Biology junior cert

● M​ovement - walking, running, flying ● R​espiration - the releases of energy from food ● S​ensitivity - the way living things respond to their environment ● N​utrition - the way a living thing gets its food ● E​xcretion - the removal of metabolic waste from the body ● R​eproduction - the formation of new individuals ● G​rowth - organisms get bigger as cells divide

● Cell membrane - holds in the contents of the cell and controls what substances enter and leave the cell ● Cytoplasm - a watery fluid in which many cell reactions take place ● Nucleus - controls the activities of the cell and contains genetic information (chromosomes)

● Cell wall - provides support and structure to plant cells ● Cell membrane ● Cytoplasm ● Chloroplasts - these contain chlorophyll which makes food for plant cells in photosynthesis ● Vacuole - stores food, water and fat

● A ​cell​ is the smallest part of a human being e.g red blood cells ● Tissue​ refers to a group of similar cells working together to carry out the same function e.g blood, phloem ● Organ​ refers to two or more tissues working together e.g heart ● System​ refers to a number of organs working together to carry out a function e.g digestive system ● Organism ​refers to a living thing

● Digestion ​refers to the breakdown of food ● Digestion is necessary to break down large, insoluble food into smaller, soluble particles so that the nutrients can be carried around the body and used ● Physical digestion ​involves teeth breaking down food ● Chemical digestion i​ nvolves the use of enzymes to break down food

Physical digestion - teeth break down food into smaller pieces by chewing ● Chemical digestion - salivary glands makes saliva which contains the enzyme amalyse, which digests starch to produce the sugar maltose

● Passes food to your stomach ● A muscular tube that forces food down to the stomach by using a wave of muscular action known as peristalsis

● Muscular bag that holds two litres of food ● Physical digestion - muscular walls churn and mix the food into chyme ● Chemical digestion - secretes hydrochloric acid to kill and soften food

● 6m long ● Digested food passes into the bloodstream ● Produces many enzymes to complete the digestion ● Two important liquids are added here: 1. Pancreatic juice (produced in the pancreas) 2. Bile (produced in the liver)

● Produces amalyse and pancreatic juice ● Produces enzymes that pass into the small intestine to help with digestion

● Produces bile which helps to digest and break down fat

● Mainly fibre, dead cells and water reach here ● Most of the water is absorbed into the bloodstream ● Too much liquid content will result in diarrhea ● Too much liquid taken back causes constipation ● Faeces are stored in the rectum ● Eventually excreted out of the anus, roughly 24-48hrs after eating

● Catalysts ​are chemicals that speeds up a reaction without getting used up in the reaction itself ● Enzymes ​are biological catalysts and proteins ● The substance that an enzyme acts on is the ​substrate a​ nd the substance formed by the reaction is the ​product ● Amalyse ​is an enzyme found in s​ aliva ● Amalyse ​breaks down ​starch ​to form a sugar called m​ altose ● Therefore, ​starch ​is the ​substrate a​ nd ​maltose ​is the ​product

● Genetics ​refers to the study of how traits/characteristics are inherited

Human Characteristics ● One nose ● Two eyes ● Fingernails Variations ● Height ● Accent ● Interests Inherited Characteristics ● Controlled by genes ● Passed on from parents to children ● Eye colour, shape of face, ability to produce substances such as saliva Non Inherited Characteristics ● Not controlled by genes ● Learned throughout life ● Reading, musical instrument Chromosomes ● Thread like structures ● Found in the nucleus ● Made of DNA and protein ● Contain genes (a section of DNA that can produce protein) Chromosome numbers ● 46 chromosomes in the body ● 23 pairs (sperm and eggs only have 23 chromosomes altogether) ● At fertilisation, the number doubles to 46

Functions of blood ● Transports substances around the body ● Defence against diseases ● Keeps body temperature constant Plasma ● Liquid ● Pale, yellow colour ● Mostly consists of water and dissolved substances ● Carries chemicals around the body (such as food and waste) Red blood cells ● Formed in bone marrow ● Contains a red, iron based pigment called haemoglobin, which transports oxygen White blood cells ● Formed in bone marrow ● Produces antibodies to fight infections and diseases Platelets ● Formed in bone marrow ● Tiny fragments of larger cells ● Helps clot blood to prevent blood loss and pathogens from entering the body

● Blood ● Heart ● Blood vessels ➢ Arteries ➢ Veins ➢ Capillaries

Artery ● Thick walls ● Small lumen ● Blood carried under high pressure away from heart ● No valves ● Oxygen-rich blood Vein ● Thin walls ● Large lumen ● No pressure in blood flow ● Has valves to protect backflow of blood ● Oxygen-rich blood ● Carries blood to the heart Capillaries ● Very thin walls ● Tiny lumen ● Blood flow under low pressure ● No valves ● Connects arteries and veins ● Materials exit and leave the blood through capillaries

Sunlight Carbon dioxide + Water ————> Glucose + Oxygen Chlorophyll

Sunlight 6CO​2​ + 6H​2O​ —————> C​6​H​2​O​6​ + 6O​2 Chlorophyll

● Glucose ➢ Provides energy for respiration ➢ Type of sugar used by plant for energy ➢ Excess glucose stored in the form of starch ➢ Forms cellulose for new cell walls ​ Sunlight Carbon dioxide + Water ————> Glucose + Oxygen Chlorophyll Sunlight 6CO​2​ + 6H​2O​ —————> C​6​H​2​O​6​ + 6O​2 Chlorophyll ● Oxygen ➢ Waste product ➢ Recycled through respiration to get chemical energy out of food

Asexual Reproduction ● One parent plant ● Gametes (sex cells) are not involved ● The offspring are genetically identical to parent plant ● Example is when strawberry plants form runners Sexual Reproduction ● Two parents needed ● A male and a female gamete is needed to fuse together to form a zygote ● New organism is not genetically identical to either parent ● Example is flowering plants

Petal ● Protects inside the flower - reproductive parts ● Brightly coloured petals attracts insects - imported for pollination Carpel ● Female reproductive part of the flower Stamen ● Male reproductive part of the flower Sepal ● Protects flower before blooming (when flower is just a bud)

● Ecology ​refers to the study of the relationships between plants, animals and their environment