E. coli has two oxygen sensors: FNR (fumarate-nitrate reductase) and ArcBA (Anoxic Redox Control, two component control systems). FNR directly senses the oxygen, while the interaction of ArcB with…
Salivary Glands: Important in Digestion What They Are Salivary glands are accessory organs that are part of the digestive system of humans. Humans have three pairs of salivary glands. Types and Localization There are three types of salivary glands: - Parotid glands: They are located before and below the ears, between the masseter muscle and the cutis.
Flower: Important Reproductive Function of Vegetables Introduction When we think of flowers, we often remember them in their colorful and eye-catching form; however, this feature is only presented by some types. There are flowers that are very small and greenish, such as the range flowers.
TREES: Several species with different names Knowing the popular and scientific names of some tree species We know many tree species by the common (popular) name, ie the names people gave and went from generation to generation through popular culture. . But botanists (researchers who study plant species) and other scientists who study trees have come up with scientific names.
Gutation: Water Elimination by Plants What is Gutation is the process by which a plant eliminates water in a liquid state. How Plant Gutation Occurs Gutation occurs in the leaves of plants, more precisely in structures on their edges called hydrodes. The amount of water eliminated in guttation varies from species to species.
Paleobotany: study of plant fossils What it is (definition) Paleobotany is a science that studies plant fossils and seeks to reconstruct the form, structure and development of plants in the past. Also called Plant Paleontology, this science draws on the knowledge of various disciplines that study charcoal, seeds and pollen (palynology).
Avocado: Example of dicotyledonous What they are (definition) Also known as magnoliopsidas, dicotyledoneae are plants (angiosperms) that have two or more cotyledons in the seed. Cotyledons are the initial leaves of plant embryos. Main characteristics of dicotyledons: - Existence of two or more cotyledons in the seed.
Rhodophytes: Also known as red algae What they are Rhodophytes are red algae that live mainly in marine waters. They make up the phylum Rodophyta. There are approximately six thousand species of red algae, of which only 165 are freshwater. Main features - They have photosynthetic pigments of red color (phycoerythrin).
Chlorophyll: responsible for the green color of plants What it is (definition) Chlorophyll is a group of photosynthetic pigments present in chloroplasts (organelles present in plant cells and algae, rich in chlorophyll), responsible for the green coloration of plants. Main Characteristics of Chlorophyll Its molecular structure is similar to that of hemoglobin (the protein responsible for blood coloring, which contains iron and transports oxygen through the body through red blood cells), the difference being that hemoglobin has iron instead of magnesium.
Lichens on a stone What are lichens (definition) Lichens are living beings considered special because they are formed by a symbiosis (relationship of mutualism between two organisms where there are advantages for both individuals). The symbiosis that forms lichens occurs between an algae and a fungus. In this symbiotic relationship, algae is responsible for the production of organic food and photosynthesis.
Kingdom Plantae: existence of several classification divisions Scientific classification of Kingdom Plantae Domain: Eukaryota Kingdom: Plantae Divisions: - Green Algae Chlorophyta (green algae, chlorophytes) Charophyta (Green algae, dehydrated and carophytic) - Embryophyta (terrestrial plants) Non Vascular Plants Marchantiophyta (Hepaticophyta) - Hepatic Plants Anthocerotophyta - Antocerots Bryophyta - Mosses Vascular Plants (Tracheophyta) Lycopodiophyta - Lycopods and Selaginella Monilophyta - Ferns and Horsetail Spermatophyta - Plants that Produce Seeds Gymnospermae (Gimnospmers) Curiosities: - Before the 19th century, when plant classifications began to develop, plants were classified into only three groups: lower (algae), intermediate (bryophytes and pteridophytes) and higher (gymnosperms and angiosperms).
Moss: One of the Best-Known Bryophytes Species What they are Generic term for a group of more than 20,000 small plant species that usually grow on soil, tree trunks, and wet rock. Main characteristics of bryophytes Bryophytes are non-vascular plants (without conductive vessels) that include mosses, liverworts and antoceros.
Sap: important for the transport of plant nutrients What it is (definition) In botany, sap is a liquid that circulates in vascular plants. We can say that it is the equivalent of human blood. Sap Function The function of sap in vascular plants is to carry nutrient transport to all plant cells.
Osteoblasts acting on the production of bone matrix Types, main characteristics and functions of bone tissue cells Osteoblasts Characteristics: are located on the surface, forming columnar or cuboid shaped cell laminae. Function: They have the function of producing the bone matrix, through the process of synthesis of the organic components of this matrix, collagen and glycoproteins.
Animal Cell Mitosis Steps Introduction (what it is) Eventually, cells need to duplicate to make new cells. This cell division occurs in two ways: through mitosis and meiosis. In this text we will approach mitosis. Practically, we can understand that in mitosis the cell doubles to give rise to two new cells.
Library: the nuclear envelope of the eukaryotic cell What is (definition) The library is also known as the nuclear envelope or nuclear envelope. It is that membrane that serves as a boundary between the cell cytoplasm and the cell nucleus. We found the library only in eukaryotic cells. The fact that the library exists only in eukaryotic cells makes these cells different from prokaryotic cells.
Water: a vital chemical element for humans Introduction Water is the main element for the functioning of living organisms. Life arose in water and without it there is no life. In the body of human beings it performs functions of the utmost importance. It is worth mentioning that about 70% of an adult human body is made up of water.
Cytology Questions (answers at bottom of page) 1. In an animal cell, which organelle is responsible for cellular respiration? A - Golgi Complex B - Mitochondria C - Ribosome D - Centriole __________________________________ 2. Which of the following presents plasma membrane functions in a cell?
Dengue Mosquito: aedes aegypti Introduction - What it is Dengue is classified as a virus, that is, a disease caused by viruses. The virus is transmitted to a healthy person through the bite of the infected female mosquito Aedes Aegypti. This disease can manifest itself in two ways: classical dengue and hemorrhagic dengue.
HIV-infected cell What is AIDS, also defined as AIDS, is acquired immunodeficiency syndrome. Its carriers have numerous symptoms and infections, resulting in damage to the immune system. How it attacks the body This virus primarily attacks the lymphocytes that command our body's defense.
Autism: Impaired Communication and Behavior What is Autism is a mental disorder that affects communication and human behavior. The term autism refers to the meaning: missing or lost. Knowing Autism Its definition has been used to describe various types of mental disorders, however, premature childhood autism, as it was called by child psychologist Leo Kanner in 1943, describes an infrequent set of symptoms.