Biology CT1 Year 10

What are the 8 characteristics of living organisms

Movement, Respiration, Sensitivity, Homeostasis, Growth, Reproduction, Excretion, and Nutrition

What's a handy acronym to remember the 8 characteristics of living organisms

MRS H-GREN

Respiration

(aerobic - meaning they need oxygen) respiration means they release energy

Sensitivity

They can respond/react to their surroundings and changes in their surroundings

Homeostasis

Maintaining a constant internal environment (e.g. body temperature)

Growth

Growing and developing in cell number and/or size

Reproduction

Producing offspring

Excretion

Removal of waste products (e.g. urine)

Nutrition

Obtaining and using food or energy for growth and repair

Out of Animal cells, plant cells, fungi cells, protoctists, and bacteria cells which ones have are multicellular and unicellular

Animal cells: multicellular, Plant cells: multicellular, Fungi cells: Both multicellular and unicellular, Protoctists: most unicellular, Bacteria: Unicellular

Out of Animal cells, plant cells, fungi cells, protoctists, and bacteria cells which ones have a nucleus

Animal, plant, fungi, protoctists

Out of Animal cells, plant cells, fungi cells, protoctists, and bacteria cells which ones have a cell membrane

Animal, plant, fungi, protoctists, bacteria

Out of Animal cells, plant cells, fungi cells, protoctists, and bacteria cells which ones have a cytoplasm

Animal, Plant, Fungi, Protoctists, Bacteria

Out of Animal cells, plant cells, fungi cells, protoctists, and bacteria cells which ones have mitochondria

Animal, Plant, Fungi, Protoctists

Out of Animal cells, plant cells, fungi cells, protoctists, and bacteria cells which ones have ribosomes

Animal, Plant, Fungi, Protoctists, Bacteria

Out of Animal cells, plant cells, fungi cells, protoctists, and bacteria cells which ones have a cell wall and what’s it made from

Plant cells: cellulose, Fungi cells: Chitin, Protoctists: Some, Bacteria: peptidoglycan

Out of Animal cells, plant cells, fungi cells, protoctists, and bacteria cells which ones have a permanent vacuole

Plant, Fungi, and some protoctists

Out of Animal cells, plant cells, fungi cells, protoctists, and bacteria cells which ones have chloroplasts

Plant, some protoctists

Animal cells are… heterotrophic/autotrophic/saprotrophic … what does that mean?

heterotrophic, organisms cannot make their own food, they must eat or consume other living or dead things to get energy

Plant cells are… heterotrophic/autotrophic/saprotrophic … what does that mean?

autotrophic, Organisms make their own food

Fungi cells are… heterotrophic/autotrophic/saprotrophic … what does that mean?

saprotrophic, A specific type of heterotroph that feeds on dead and rotting matter, They do not ingest food like animals do. Instead, they release special chemicals outside their bodies to dissolve dead material, and then absorb the liquid nutrients.

Bacteria cells are… heterotrophic/autotrophic/saprotrophic

Bacteria can be autotrophic, heterotrophic, or saprotrophic (also called saprophytic)

Protoctists cells are… heterotrophic/autotrophic/saprotrophic

Bacteria can be autotrophic, heterotrophic, or saprotrophic (also called saprophytic)

Nucleus

controls the cells activities, contains DNA, has its own membrane

Cell membrane

Controls what goes in and out of the cell, and holds the cell together

Cytoplasm

A gel like substance where most of the cells chemical reactions take place. It contains enzymes which control these reactions

Mitochondria

Where most of the reactions for aerobic respiration take place - transfers energy that the cell needs to work

Ribosomes

Where proteins are made in the cell

Chloroplasts

Where photosynthesis happens, which makes food for the plant. Chloroplasts contain a green substance called chlorophyll (what makes the chloroplasts green) which is used in photosynthesis

Cell wall

A rigid structure which surrounds the cell membrane - it supports the cell and strengthens it

Vacuole

contains cell sap, it helps support the cell by keeping the cytoplasm up against the cell wall

Bacterial pathogen example and what is it

Pneumococcus, spread by coughs or sneezes, when lungs become infected the pathogen can cause diseases such as bronchitis or pneumonia. Controlled by following good hygiene practices to prevent infection.

Fungal pathogen example and what is it

Diplocarpon rosae (D. rosae), a serious pathogen that causes a disease called rose black spot in wild and cultivated roses, Infected roses develop purple or black spots on leaves, which often turn yellow and drop early, and sometimes small black scab-like spots develop on young stems. This pathogen affects the cells ability to photosynthesise and therefore reduces the plant’s ability to make the food it needs to survive. The most effective way to treat rose black spot is to remove any infected tissues and burning, and other ways of treating them are with fungicides (chemicals which kill fungi).

Protoctist pathogen example and what is it

Plasmodium causes malaria and is spread by female mosquitoes. They suck infected blood from someone with malaria and then pass the protists on when they feed on a new person. When first infecting a human it passes to the liver and then invades red blood cells and feeds on haemoglobin. Eventually the infected red blood cells burst and releases the new Plasmodium along with toxins produced by this pathogen. Symptoms include fever, muscle pain, headaches, diarrhoea and coughing. If untreated malaria can be fatal.

Viral pathogen examples (2) and what it is

Human Immune deficiency Virus (HIV) enters the body when bodily fluids (e.g blood and semen) are mixed. The virus enters the lymph nodes and attacks the body’s white blood cells, eventually developing into a disease called AIDS (acquired immune deficiency syndrome), with the patient usually dying of unrelated diseases such as pneumonia. Tobacco mosaic virus (TMV) causes it in plants, usually infecting tobacco plants but can affect over 150 plant species including tomatoes. Leaves have discoloured ‘mosaic' patterns. This pathogen reduces photosynthesis and affects plant growth, and the quality and numbers of fruit are affected. This pathogen enters via plant wounds.

What do plant cells store

Carbohydrates as starch or sucrose

What do animal cells store

They often store carbohydrates as glycogen

What do fungi cells store

They may store carbohydrate as glycogen

What are fungi cell bodies usually organised into and what do they include many of

Their body is usually organised into a mycelium made from thread-like structures called hyphae, which contain many nuclei

Plant examples

flowering plants, such as a cereal (for example, maize), and a herbaceous legume (for example, peas or beans)

Animal examples

Mammals (for example, humans) and insects (for example, housefly and mosquito)

Fungi examples

Mucor, which has the typical fungal hyphal structure, and yeast, which is single-celled

Protoctist examples

Amoeba, that live in pond water, have features like an animal cell, while others, like Chlorella, have chloroplasts and are more like plants

What are viruses

These are not living organisms. They are small particles, smaller than bacteria; they are parasitic and can reproduce only inside living cells; they infect every type of living organism. They have a wide variety of shapes and sizes; they have no cellular structure but have a protein coat and contain one type of nucleic acid, either DNA or RNA.

Structure of a plant cell

Structure of an animal cell

Structure of a bacteria cell

Bacteria examples

Lactobacillus bulgaris: Rod shaped bacteria used to make yoghurt, and pneumococcus: Spherical-shaped, causes pneumonia.

Protoctists can be divided into 2 categories:

Plant like and Animal like

Plant like protoctist example

Animal like protoctist

Both animal like and plant like protoctist

What’s the difference between protists and protoctists

Protists are unicellular protoctists

What is a disease

A disease is an abnormal condition of an organism or part of an organism.

What is a communicable disease

A communicable disease is a disease that can be passed on from one organism to another that is caused by a pathogen.

What is a pathogen

A pathogen is an infectious agent that causes a communicable disease

What are the 4 types of pathogens

Virus, Bacteria, Protoctists, and Fungi

The Structure of the leaf

wax cuticle function

To help prevent water loss

Upper epidermis function

Thin and transparent to allow more light through to the chloroplasts

Pallaside cells

Contains lots of chloroplasts to absorb more light

Spongy cells (mesophyll)

Contains lots of air spaces to allow carbon dioxide to diffuse through the leaf and increase the surface area

Stomata (Stoma) (pore)

Holes in the leaf to allow carbon dioxide to diffuse in and oxygen to diffuse out

Guard cells

To open and close the holes, to close to prevent water loss

Xylem

Allows water absorbed by the roots to travel to the leaves

Airspace

Increases the surface area to allow oxygen and carbon dioxide to diffuse in and out of the cells

Word equation for photosynthesis

Carbon dioxide + water → Glucose + Oxygen

Symbol equation for photosynthesis

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

What is the important pigment

Chlorophyll

Photosynthesis = what energy to what energy

Light energy → Chemical energy

How to find out if photosynthesis is taking place in a plant

Test the plant for the presence of starch (glucose makes starch)

What is a limiting factor

A factor, such as light intensity, that limits a chemical reaction. If this factor increases, the rate of reaction will go faster too.

What is the Aerobic respiration word equation

glucose + oxygen → carbon dioxide + water + energy

What is the chemical equation for aerobic respiration

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O (+ energy)

How does temperature affect the rate of photosynthesis

The rate of photosynthesis is slow when the temparature is low because the particles (molecules and enzymes, which are proteins that speed up reactions) have less energy and move slowly, so they do not collide or crash into each other very often

What chemical is iodine solution used to test for and what colour does it turn if this chemical is present

Starch, blue/black

Method to find out if leaves contain starch

Why cant you simply add iodine onto a leaf to look for the presence of starch?

The waxy surface of the leaf will stop the iodine solution getting into the leaf, and the green chlorophyll will obscure any colour change with the iodine solution and starch

Why boil the leaf in ethanol before adding the iodine solution

Removes chlorophyll from the leaf so you can observe any colour change.