OCR GCSE Biology Paper 1 Flashcards

Flashcards for OCR GCSE Biology Paper 1, covering cell level systems, scaling up, and organism level systems.

What type of microscope allows us to see finer details of cells, including organelles?

Electron microscope

What is the formula for calculating magnification?

Magnification = Image size / Object size

What type of cells contain a nucleus?

Eukaryotic cells

What is the function of the cell membrane?

Keeps everything inside the cell and allows certain substances to pass through (semi-permeable).

What is the function of mitochondria?

Where respiration takes place, releasing energy for the cell to function.

What is the function of ribosomes?

Where proteins are assembled or synthesized.

How do bacteria multiply?

Binary fission

What is the term given to all the genetic material in an organism?

Genome

What is a gene?

A section of DNA that codes for a specific protein.

What is the definition of genotype?

What code is stored in your DNA specifically

What is the definition of phenotype?

How that code is expressed in your characteristics, what proteins are made.

What are enzymes?

Biological catalysts that break down larger molecules into smaller ones.

What enzyme breaks down starch into glucose?

Amylase

What happens to enzymes when they denature?

The active site changes shape, and the substrate no longer binds.

What molecule transports energy to different organelles to carry out their various functions?

ATP

What is metabolism?

The sum of all reactions in a cell or organism.

Where does photosynthesis happen in plant cells?

Chlorophyll and chloroplasts

What is diffusion?

The movement of molecules from an area of high concentration to an area of low concentration.

What is osmosis?

The diffusion of water across a semi-permeable membrane.

What is active transport?

When carrier proteins use energy to move substances through the membrane.

What are diploid cells?

Cells that humans have 23 pairs of chromosomes in every nucleus.

What are haploid cells?

Gametes; they have half (23, not 23 pairs) of the amount of chromosomes as diploid cells.

What is mitosis?

The process by which cells make new cells for growth and repair.

What are stem cells?

Cells that haven't yet specialized.

What two systems does the circulatory system consist of?

The heart, and the blood vessels.

What is the double circulatory system?

Double circulatory system: blood enters the heart twice every time it's pumped around the body.

What is the definition of arteries?

Blood vessels that go away from the heart.

What is the definition of veins?

Blood vessels that go towards the heart.

What are the components of blood?

Plasma, platelets, red blood cells, and white blood cells.

Where does photosynthesis take place?

Leaves

What is transpiration?

The diffusing of water into roots and up the xylem.

Which way does xylem flow?

Unidirectional, only goes in one direction

what is translocation?

Translocation is bidirectional; pholem are the conveyor belts of cells that transport sugars, food, and sap up and down the plant.

What is chlorosis?

The scientific term for the yellowing of leaves.

What is homeostasis?

The term given to an organism's ability to regulate internal conditions.

What is the central nervous system (CNS) consists of?

The brain and spinal cord

What is the peripheral nervous system (PNS) consists of?

The nerves that go through the rest of the body.

What is accommodation in the eye?

The eye's ability to change the shape of the lens in order to focus light from objects at different distances.

What is myopia?

The medical term for shortsightedness

What is hyperopia?

Long-sightedness.

What is thermoregulation?

Your body controlling its internal temperature.

What is the endocrine system?

A system of glands that produce, use, or secrete hormones that travel to effectors via the blood.

What is the pituitary gland?

Considered the main gland, as it produces hormones in response to stimuli that travel to other glands.

What hormone does the pancreas secrete if blood glucose levels are too high?

Insulin

What hormone does the pancreas secrete if blood glucose levels are too low?

Glucagon

How does the body loses water?

When you exhale, sweat, or urinate.

What is menstruation?

Occurs in females after puberty; eggs start to mature.

What is FSH?

Follicle-stimulating hormone; made by the pituitary gland, causes an egg to mature in the ovary.

What is LH?

Luteinizing hormone; causes the egg to be released.

What is adrenaline?

The hormone that increases heart and breathing rate in stressful situations.

What hormone controls metabolic rate?

Thyroxin

What is phototropism?

Auxins control shoot and root growth, are destroyed by sunlight, gathers on the shaded side of a shoot, causing more growth and elongation of cells on the shaded side, so the shoot bends toward the sun or light source.

What is geotropism?

In roots auxins inhibit growth, the hormone gathers on the bottom of a root, and so that means the top side grows more quickly, causing the root to grow downwards.

What two systems does the circulatory system consist of?

The heart and blood vessels.

What is the double circulatory system?

Double circulatory system: blood enters the heart twice every time it's pumped around the body.

What is the definition of arteries?

Blood vessels that go away from the heart.

What is the definition of veins?

Blood vessels that go towards the heart.

What are the components of blood?

Plasma, platelets, red blood cells, and white blood cells.

What is the endocrine system?

A system of glands that produce, use, or secrete hormones that travel to effectors via the blood.

What is the pituitary gland?

Considered the main gland, as it produces hormones in response to stimuli that travel to other glands.

What hormone does the pancreas secrete if blood glucose levels are too high?

Insulin

What hormone does the pancreas secrete if blood glucose levels are too low?

Glucagon

How does the body loses water?

When you exhale, sweat, or urinate.

What is menstruation?

Occurs in females after puberty; eggs start to mature.

What is FSH?

Follicle-stimulating hormone; made by the pituitary gland, causes an egg to mature in the ovary.

What is LH?

Luteinizing hormone; causes the egg to be released.

What is adrenaline?

The hormone that increases heart and breathing rate in stressful situations.

What hormone controls metabolic rate?

Thyroxin

What is the central nervous system (CNS) consists of?

The brain and spinal cord

What is the peripheral nervous system (PNS) consists of?

The nerves that go through the rest of the body.

What is accommodation in the eye?

The eye's ability to change the shape of the lens in order to focus light from objects at different distances.

What is myopia?

The medical term for shortsightedness

What is hyperopia?

Long-sightedness.

What is a reflex arc?

Rapid, involuntary, and preprogrammed response to a specific stimulus.

What is the typical pathway of a reflex arc?

Sensory receptor, sensory neuron, relay neuron (spinal cord), motor neuron, effector.

What is the synapse?

The gap between two neurons where neurotransmitters are released to transmit a signal.

What role does estrogen play in the menstrual cycle?

Estrogen, secreted by the ovaries, causes the lining of the uterus to thicken.

What is the role of progesterone in the menstrual cycle?

Progesterone maintains the lining of the uterus and is secreted by the corpus luteum after ovulation.