Biology

Question 1

Homeostasis Def.

Answer 1

Maintaining A Constant Internal Environment

Question 2

Control System Pathway

Answer 2

Receptors —> Coordination Centre —> Effectors

Question 3

Pituitary Gland Def.

Answer 3

Stimulates Production Of Hormones

Question 4

Thyroid Gland Def.

Answer 4

Produces Hormones, Regulates Metabolic Rate

Question 5

Adrenal Glands Def.

Answer 5

Produces Hormones To Regulate Metabolism & Blood Pressure, Create “Fight Or Flight” Body Response

Question 6

Pancreas Def.

Answer 6

Produces Hormones Insulin & Glucagon

Question 7

Ovaries Def.

Answer 7

Produce Hormone Oestrogen & Regulate Menstrual Cycle

Question 8

Testes Def.

Answer 8

Produces Hormone Testosterone & Stimulates Sperm Production

Question 9

Human Nerves System Pathway

Answer 9

Stimulus —> Receptor —> Sensory Neurones —> Coordinator —> Motor Neurones —> Effector —> Response

Question 10

Examples Of Reflex Actions

Answer 10

Blinking, Breathing, Coughing Sneezing, Etc

Question 11

Synapse Def.

Answer 11

Junctions Between Neurones

Question 12

Ruler Drop (Reaction Rate) Practical Steps

Answer 12

• One Person Holds Ruler (From 0cm) Above The Second Persons Hand
• Person Drops Ruler & Starts Timer
• Second Person Detects This From Peripheral Vision
• Second Person Catches Ruler
• Repeat & Calculate Mean Result

Question 13

Pancreatic Hormones And Use

Answer 13

Insulin (Decreases Blood Glucose Levels Back To Normal), Glucagon (Increases Glucose Levels Back To Normal)

Question 14

Type 1 Diabetes & Def.

Answer 14

Pancreas Fails To Produce Insulin. Treated With Insulin Injections

Question 15

Type 2 Diabetes Def. & Treatment

Answer 15

Body Cells No Longer Respond To Insulin, Treated With Healthy Diet & Exercise

Question 16

FSH Hormone Def.

Answer 16

(Produces In Ovaries) Matures Egg

Question 17

LH Hormone Def.

Answer 17

(Produced In Ovaries) Stimulates Release Of Egg

Question 18

Oestrogen & Progesterone Def.

Answer 18

(Produced In Ovaries) Maintains Uterus Lining & Prepares For Pregnancy

Question 19

Testosterone Def.

Answer 19

(Produced In Testes) Stimulates Production If Sperm

Question 20

Examples Of Hormonal Contraception

Answer 20

Oral (BC. Pill), Progesterone Injections / Patch

Question 21

Examples Of Non-Hormonal Contraception

Answer 21

Barrier Method (Condoms), Implant (Coil), Sterilisation (Permanent - Vasectomy)

Question 22

IVA/F Steps

Answer 22

• Mother Is Given FSH & LH Injections
• Eggs (From Mother) Are Fertilised By Sperm From Father
• Premature Embryos Inserted Into Mother’s Uterus

Question 23

Ethical Issues With IVA/F

Answer 23

High Chance Of Embryo Being Destroyed In Uterus Or Fertilisation Process, Against “God’s Plan”

Question 24

Adrenaline Def.

Answer 24

Produced In Adrenal Gland, Creates “Fight Or Flight” Response In Body

Question 25

Thyroxine Def.

Answer 25

Produced In Thyroid Gland, Stimulates Metabolism & Maintains Body Temp

Question 26

Sexual Reproduction (In Humans)

Answer 26

Egg (23 C.) + Sperm (23 C.) —> Zygote (Embryo - 46C. / 23 Pairs)

Question 27

Asexual Reproduction (In Plants)

Answer 27

(Mitosis) Prophase —> Metaphase —> Anaphase —> Telophase —> Cytokinesis

Question 28

Mitosis Def.

Answer 28

One Division, Two Identical Daughter Cells

Question 29

Meiosis Def.

Answer 29

Two Divisions, Four Identical Daughter Cells, Only In Gametes

Question 30

Nucleus Def.

Answer 30

Contains Chromosomes

Question 31

DNA Def.

Answer 31

Contains Genetic Instructions For Development & Function Of An Organism

Question 32

Genetic Inheritance Def.

Answer 32

1 Gamete Cell = 46 Chromosomes / 23 Pairs In Each Pair There Is One Chromosome Inherited From Mother & One From Father

Question 33

Genome Def.

Answer 33

Entire Genetic Material Of An Organism

Question 34

Genetic Mutation Def.

Answer 34

DNA Changes - Alters Instructions

Question 35

Gene Def.

Answer 35

Sections Of DNA In A Chromosome

Question 36

Allele Def.

Answer 36

Variations Of Given Gene

Question 37

Homozygous Def.

Answer 37

Two Identical Alleles

Question 38

Heterozygous Def.

Answer 38

Two Different Alleles

Question 39

Genotype Def.

Answer 39

Genetic Make Up Of An Individual Orgainism

Question 40

Phenotype Def.

Answer 40

Observable Characteristics Of An Individual, E.g: Eye Colour / Petal Colour

Question 41

Dominant Def.

Answer 41

The Allele That Is Always Expressed In A Phenotype

Question 42

Recessive Def.

Answer 42

An Allele That Shows Up In The Phenotype Only When It Is Heterozygous

Question 43

Polydactyl Disorder Def.

Answer 43

Having Too Many Fingers / Toes, Inherited By Parent With Dominant Gene

Question 44

Cystic Fibrosis Disorder Def.

Answer 44

Breathing Condition, Causes Mucus Build Up In Lungs, Must Have Two Parents With / Carrying Condition As The Allele Is Recessive

Question 45

Embryo Screening Def.

Answer 45

Observing Embryo In Uterus To Check For Any Mutations Or Medical Disorders

Question 46

(Genetic) Variation Def.

Answer 46

The Phenotype Of An Organism Is Determined By A Combination Of It’s Genotype & How It Interacts With It’s Environment

Question 47

How Do Mutations Happen? (Origin)

Answer 47

All Genetic Variations In A Population Originate From Past Mutations (Changes In DNA) - Benefits Survival Chances Of An Organism